font size

DECISION of the Gosgortekhnadzor of the Russian Federation dated 05-05-2003 29 ON THE APPROVAL OF GENERAL EXPLOSION SAFETY RULES FOR EXPLOSION AND FIRE HAZARDOUS... Relevant in 2018

4.6. Chemical reaction processes

4.6.1. Technological systems that combine several processes (hydrodynamic, heat and mass transfer, reaction) are equipped with devices for monitoring regulated parameters. Control, regulation and emergency protection means must ensure stability and explosion safety of the process.

4.6.2. The technological equipment of reaction processes for units of any explosion hazard category is equipped with means of automatic control, regulation and protective interlocking of one or a group of parameters that determine the explosion hazard of the process (the amount and ratio of incoming starting substances, the content of components in material flows, the concentration of which in the reaction equipment can reach critical values, pressure and temperature of the medium, quantity, flow rate and parameters of the coolant, etc.). At the same time, the technological equipment included in the installation with technological blocks of explosion hazard category I is equipped with at least two sensors for each dangerous parameter (one sensor for each for dependent parameters), means of regulation and emergency automatic protection, and, if necessary, backup systems control and protection.

4.6.3. Trigger automatic systems emergency protection must be carried out according to specified programs (algorithms).

4.6.4. In reaction process control systems in process units with QB<= 10, допускается использование средств ручного регулирования при условии автоматического контроля опасных параметров и сигнализации, срабатывающей при выходе их за допустимые значения.

4.6.5. In reaction processes occurring with the possible formation of intermediate peroxide compounds, explosive by-products of resinization and compaction (polymerization, polycondensation) and other unstable substances with their probable deposition in equipment and pipelines, the following is provided:

control over the content of impurities in incoming raw materials that contribute to the formation of explosive substances, as well as the presence of unstable compounds in intermediate products and ensuring the specified regime;

introduction of inhibitors that prevent the formation of dangerous concentrations of unstable substances in the equipment; fulfillment of special requirements for the quality of the construction materials used and the cleanliness of the surface treatment of devices, pipelines, fittings, sensors of devices in contact with products circulating in the process;

continuous circulation of products and raw materials in capacitive equipment to prevent or reduce the possibility of deposition of solid explosive unstable products;

removal of the reaction mass enriched with dangerous components from the equipment;

ensuring established regimes and storage times for products that can polymerize or resin, including the timing of their transportation.

The choice of necessary and sufficient conditions for organizing the process is determined by the process developer.

Methods and frequency of monitoring the content of impurities in raw materials, unstable compounds in the reaction mass of intermediate and final products, the procedure for removing the reaction mass containing dangerous by-products, modes and storage time of products are established by the process developer and are reflected in the design documentation and technological production regulations.

4.6.6. If there is a possibility of deposits of solid products on the internal surfaces of equipment and pipelines, their clogging, including emergency drainage devices from technological systems, control over the presence of these deposits and measures for their safe removal are provided, and, if necessary, backup equipment.

4.6.7. When using catalysts, including organometallic catalysts, which, when interacting with atmospheric oxygen and (or) water, can spontaneously ignite and (or) explode, it is necessary to take measures to exclude the possibility of supplying raw materials, materials and inert gas containing oxygen and (or) to the system. moisture in quantities exceeding the maximum permissible values. Permissible concentrations of oxygen and moisture, methods and frequency of monitoring their content in the initial products are determined taking into account the physico-chemical properties of the catalysts used, the explosion hazard category of the technological unit and are regulated.

4.6.8. The dosage of components in reaction processes should be predominantly automatic and carried out in a sequence that excludes the possibility of the formation of explosive mixtures or uncontrolled reactions inside the equipment, which is determined by the process developer.

4.6.9. To eliminate the possibility of overheating of the substances involved in the process, their self-ignition or thermal decomposition with the formation of explosive and fire hazardous products as a result of contact with heated elements of the equipment, temperature conditions, optimal speeds of movement of products, and the maximum permissible time of their stay in the high temperature zone are determined and regulated.

4.6.10. To eliminate the danger of uncontrolled development of the process, measures should be taken to stabilize it, emergency localization or release of devices.

4.6.11. The use of residual pressure of the medium in a batch reactor to press the reaction mass into another apparatus is permitted in individual, justified cases.

4.6.12. Equipment for liquid-phase processes is equipped with systems for monitoring and regulating the liquid level in it and (or) means for automatically shutting off the supply of this liquid to the equipment when a specified level is exceeded or other means that exclude the possibility of overflow.

4.6.13. Reaction devices for explosive technological processes with mixing devices are, as a rule, equipped with means of automatic monitoring of the reliable operation and tightness of the mixer shaft seals, as well as interlocks that prevent the possibility of loading products into the equipment when the mixing devices are not working in cases where this is required by the conditions of the process. and ensuring security.

4.6.14. Reaction equipment, in which the removal of excess reaction heat during heat transfer through the wall is carried out due to the evaporation of the coolant (refrigerant), is equipped with means of automatic monitoring, regulation and signaling of the refrigerant level in the heat exchange elements.

4.6.15. In cooling systems for reaction equipment with liquefied gases:

the refrigerant temperature (boiling point of liquefied gas) is ensured by maintaining equilibrium pressure, the value of which must be regulated automatically;

measures are provided to automatically ensure the release (draining) of the refrigerant from the heat exchange elements of the reaction equipment, as well as measures to exclude the possibility of pressure increasing above the permissible level in the cooling systems in the event of a sudden shutdown.

4.6.16. Development and implementation of reaction processes in the production or use of products characterized by high explosiveness (acetylene, ethylene at high parameters, peroxide, organometallic compounds, etc.), prone to thermal decomposition or spontaneous spontaneous polymerization, self-heating, and also capable of self-ignition or explosion upon interaction with water and air, must be carried out taking into account these properties and provide additional special safety measures.

CALCULATION OF THE CONSEQUENCES OF AN EXPLOSION

INSIDE THE TECHNOLOGICAL EQUIPMENT

The development of the chemical industry is accompanied by an increase in the scale of production, the capacity of installations and apparatus, and the complication of technological processes and production management modes. Due to the complication and increase in production, accidents that occur have increasingly serious consequences. Of particular danger are chemical and explosive production facilities, nuclear power plants, warehouses for explosive and flammable substances, ammunition, as well as vessels and tanks intended for storing and transporting petroleum products and liquefied gases.

Currently, the world is paying more and more attention to the issues of ensuring a high level of environmental protection, life safety and labor protection. One of the possible ways to reduce the risk of emergency situations at industrial facilities is to analyze the accidents that have occurred. On their basis, measures are developed to prevent accidents and prevent dangerous consequences.

One type of accident at industrial facilities is explosions of technological equipment. An explosion of equipment carries a potential danger of injuring people and has destructive capabilities.

Explosion (explosive transformation) is a process of rapid physical or chemical transformation of a substance, accompanied by the transition of the potential energy of this substance into mechanical energy of movement or destruction. Depending on the type of energy carrier and the conditions of energy release during an explosion, chemical and physical energy sources are distinguished.

A physical explosion can be caused by the sudden destruction of a vessel with a compressed gas or superheated liquid, mixing of superheated solids (melt) with cold liquids, etc.

The source of a chemical explosion is fast-paced, self-accelerating exothermic reactions of interaction of flammable substances with oxidizing agents or thermal decomposition of unstable compounds.

Physical explosions in equipment

Physical explosions are usually associated with explosions of vessels from gas or vapor pressure.

In chemical technology, it is often necessary to deliberately compress both inert and flammable gases, expending electrical, thermal or other types of energy. In this case, the compressed gas (steam) is located in sealed devices of various geometric shapes and volumes. However, in a number of cases, compression of gases (vapors) in technological systems occurs accidentally due to the excess of the regulated heating rate of the liquid by the external coolant.

Explosions of pressure vessels can produce strong shock waves and create large numbers of fragments, leading to serious damage and injury. In this case, the total energy of the explosion is converted mainly into the energy of the shock wave and the kinetic energy of the fragments.

Many liquids are stored or used in conditions where their vapor pressure significantly exceeds atmospheric pressure. The energy of overheating a liquid can be a source of purely physical explosions, for example, during intensive mixing of liquids with different temperatures, when the liquid comes into contact with molten metals and heated solids. In this case, no chemical transformations occur, and the superheating energy is spent on vaporization, which can occur at such a speed that a shock wave occurs. The mass of the generated vapors and the rate of vaporization are determined by the material and heat balances of two possible models of emergency situations: 1) heat release with vaporization occurs at a constant volume; 2) heat release while maintaining volume is followed by expansion while maintaining thermal equilibrium.

When two liquids with significantly different temperatures are mixed, physical detonation phenomena are possible with the formation of a cloud of liquid droplets of one of the components.

In industrial enterprises, neutral (non-flammable) compressed gases - nitrogen, carbon dioxide, freons, air - are found in large volumes, mainly in high-pressure spherical gas holders.

On July 9, 1988, an explosion occurred in a spherical compressed air gas tank with a volume of 600 m3 (sphere radius 5.25 m), made of steel with a wall thickness of 16 mm and designed to operate under a pressure of 0.8 MPa. The explosion of the gas tank (which occurred at a pressure of 2.3 MPa) was preceded by a slow increase in pressure to the yield point of the steel from which it was made.

The ball gas holder was part of the urea production process unit, which was put into operation in April 1988. Air entered the gas holder from the common plant process line through a check valve and fittings. The gas tank was not equipped with means of pressure relief, since the maximum possible air pressure (0.8 MPa) in it was ensured by its stabilization in the technological system and the characteristics of air compressors of the VP-50-8 type. Pressure control was carried out by local indicating and recording pressure gauges on the control panel.

From the gas tank, air was supplied through a pipeline system for technological needs, including to the department for purifying CO2 from flammable impurities. In this compartment, air from the gas tank was diverted through a pipeline with a diameter of 150 mm into the discharge line of a CO2 turbocompressor of the “Babette” type, operating at a pressure of 2.3 MPa and at the same time being the receiving line of a piston compressor (4DVK-210-10) boosted to 10.0 MPa; the supplied air was intended for purging the compression system and through it the process line from CO2 before repairs.

Upon completion of the repair of the process unit, the CO2 turbocompressor was turned on and after 10 minutes, when the pressure in the discharge line moved to 2.3 MPa, the piston compressor was turned on with adjustment to the operating pressure of 10.0 MPa. After the CO2 centrifugal compressor was started, the pressure in the air gas tank began to increase; at the same time, the pressure gauge with a scale of 0.8 MPa on the control panel went off scale. Dioxide, through a loosely closed valve, from the discharge pipeline of a working centrifugal compressor entered the air gas tank through the air line. The gas pressure in the gas holder increased for 4 hours, which led to the destruction of the gas holder due to excess pressure.

The entry of CO2 into the air gas tank is confirmed by a decrease in air temperature to 0°C due to throttling of CO2 with the discharge pressure of the centrifugal compressor to the pressure in the gas tank.

In areas of low shock wave pressure, up to 100% of the glazing in six industrial buildings located at a distance of m from the installation site of the exploded gas tank was destroyed; minor damage to glazing (up to 10%) was observed in residential buildings located 2500 m from the explosion site.

Flying fragments of the gas tank shell posed a great danger.

Chemical explosions in equipment

Exothermic chemical reactions are carried out in technological systems (reactors) that are thermally balanced. The heat released during the reaction is removed by an external refrigerant through the walls of heat exchange elements with heated reaction products or with excess raw materials due to its evaporation, etc. The stable course of the reaction process is ensured by the equality of the rates of heat release and heat removal. The rate of reaction and, accordingly, heat influx increases according to a power law with increasing concentration of reagents and quickly increases with increasing temperature.

When a chemical reaction gets out of control, the following explosion mechanisms are possible.

1. If the reaction mass is a condensed explosive, detonation of the product is possible when a critical temperature is reached; in this case, the explosion will occur according to the mechanism of explosion of a point explosive charge in the shell. The explosion energy will be determined by the TNT equivalents of the entire mass of explosives in the system.

2. Under conditions of gas-phase processes, thermal decomposition of gases or explosive combustion is possible gas mixture; they should be considered as gas explosions in closed volumes, taking into account real energy potentials and TNT equivalents.

3. In liquid-phase processes, an emergency explosive energy release is possible: overheating of the liquid and increasing the vapor pressure above it to a critical value.

The total energy of the cloud explosion will be equal to the sum of the equivalent heats of combustion of the vapors present in the system and additionally formed during the evaporation of the liquid.

The reasons for an exothermic chemical reaction running out of control are often a decrease in heat flow in liquid-phase batch processes with large masses of reactants and limited heat removal capabilities by conventional methods. Such processes include, in particular, bulk polymerization of the monomer, in which the reaction rate is regulated by conventional methods, as well as by the dosage of initiating substances. In case the process gets out of control, additional substances are introduced into the reaction mass that reduce the rate or suppress the exothermic reaction.

Some substances can polymerize more or less spontaneously, and normal polymerization reactions will be exothermic. If the monomer is volatile, as is often the case, a stage is reached at which a dangerous increase in pressure can occur. Sometimes polymerization can only occur at elevated temperatures, but for some substances, such as ethylene oxide, polymerization can begin at room temperature, especially when the starting compounds are contaminated with polymerization accelerating substances.

Similar accidents have occurred during the polymerization of vinyl chloride and other monomers, in chloroprene storage facilities and in railway tanks with liquid chlorine, hydrocarbons and other active compounds, when substances that interact with the products contained in them were mistakenly pumped into them. When the heat release significantly exceeds the heat removal during such accidents, the technological system completely opens up, during which the pressure sharply decreases, the rate of the chemical reaction decreases, or it stops completely. In this case, the total energy potential is the sum of the equivalent energies of combustion of vapors (gases) located above the liquid and formed as a result of evaporation under the influence of the heat of overheating the liquid to a temperature corresponding to the critical conditions for the destruction of the system.

Also, the simplest case of an explosion is a decomposition process that produces gaseous products. One example is hydrogen peroxide, which decomposes with significant heat of reaction, yielding water vapor and oxygen:

2H2O2 -> 2H2O + O2 - 23.44 kcal/mol

As a household product, hydrogen peroxide is sold as 3% aqueous solution and poses little danger. The situation is different with hydrogen peroxide." high standard", the concentration of which is 90% or more. The decomposition of such H2O2 is accelerated by a number of substances that are used as jet fuel or in a gas turbine to pump fuel to the main engines.

One example is redox reactions and condensations:

1). Redox reactions, in which air or oxygen reacts with a reducing agent, are quite common and form the basis of all combustion reactions. In cases where the reducing agent is an undispersed solid or liquid, combustion reactions do not occur quickly enough to become explosive. If the solid is finely divided or the liquid is in the form of droplets, then a rapid increase in pressure is possible. This can lead, in a closed volume, to an increase in excess pressure up to 0.8 MPa.

2). Condensation reactions are very common. They are particularly widely used in the production of paints, varnishes and resins, where they serve as the basis for processes in continuous reactors with heating or cooling coils. Many examples of uncontrolled reactions have been recorded due to the fact that the rate of heat transfer in such vessels is linear function the temperature difference between the reaction mass and the coolant, while the reaction rate is an exponential function of the temperature of the reactant. However, due to the fact that the rate of heat release, as a function of the concentration of the reactants, decreases during the reaction, the undesirable effect is compensated to some extent.

Thus, the energy of an explosion caused by an exothermic chemical reaction running out of control depends on the nature of the technological process and its energy potential. Such processes, as a rule, are equipped with appropriate controls and emergency protection, which reduces the possibility of an accident. However, chemical reactions are often a source of uncontrolled energy release in equipment that does not provide organized heat removal. Under these conditions, self-accelerating chemical reactions that begin inevitably lead to the destruction of technological systems.

Accident statistics

Table 1 presents data on accidents associated with explosions inside process equipment.

Table 1 - List of accidents that occurred

Date and place accidents	Type of accident	Description of the accident and main reasons	The scale of the accident development, the maximum zones of action of damaging factors	Number of victims	A source of information

Jonava	Storage tank explosion	The polymerization of vinyl acetate generated heat sufficient to create destructive pressure.	Tank destruction.
	Destruction of the oxidation apparatus	When the exothermic reaction of isopropylbenzene oxidation with air got out of control, the apparatus was destroyed due to a sharp rise in pressure.	Destruction of the apparatus.
Sumgayit PA warehouse	Explosion of a spherical tank	Due to the onset of the butadiene polymerization process, the tank was destroyed.	The explosion of the tank resulted in the explosion of the tank. Shrapnel damaged neighboring tanks and a building.

Continuation of Table 1


	Gas tank explosion	The explosion of the gas tank was preceded by a slow increase in pressure to the yield point of steel.	At a distance of m from the gas tank, the glazing was 100% destroyed, 2500 m – 10%.
02.1990 Novokuybyshevsk Refinery	Vessel explosion	The vessel collapsed as a result of exceeding the vapor pressure of the propane-butane fraction in the separator.	Destruction of the container along the solid metal shell.
	Reactor explosion	As a result of an exothermic chemical reaction of nitromass decomposition and excess pressure, the reactor exploded.	The building in which the reactor was located was destroyed.
07.1978 San Carlos	Tanker shell rupture		The fragments scattered over a distance of 250 m, 300 m, 50 m. The tractor ended up at a distance of 100 m.
07.1943 Ludwigsgafen,	Tank explosion	Due to excess hydraulic pressure	Shell destruction.

Continuation of Table 1


Germany		a tank containing a butane-butylene mixture collapsed.
07.1948 Ludwigsgafen, Germany	Dimethyl ether tank explosion	The tank collapsed due to excessive hydraulic pressure.	Shell destruction.
02/10/1973 New York, USA	Explosion in a tank	During repairs to the tank, natural gas vapor exploded from a spark.	Tank destruction.	40 people died, 2 were injured.
10/24/1973 Sheffield, England	Underground tank explosion	Explosion of material residues from flame cutting equipment.	The radius of destruction was about half a kilometer.	3 people died, 29 were injured
12/19/1982 Caracas, Venezuela	Tank explosion	A tank with 40 thousand tons of fuel exploded at an oil storage warehouse	Burning oil poured into the city and into the sea. A tanker caught fire in the bay and another tank on the shore exploded.	140 people died and more than 500 were injured.
06/20/2001 Catalonia, Spain	Tank explosion	An explosion in a tank containing industrial alcohol occurred at a chemical plant.		2 people died

Calculation method

In case of equipment explosions, the main damaging factor is an air shock wave.

When assessing the parameters of an emergency explosion of a container with an inert gas (mixture of gases), it is assumed that the shell has a spherical shape. Then the stress in the wall of the spherical shell is determined by the formula:

σ = ΔP r/(2d), (1)

where σ is the stress in the wall of the spherical shell, Pa;

ΔP – pressure drop, Pa;

r – radius of the shell wall, m;

d – shell wall thickness, m.

Transformation of formula (1) allows you to calculate the destruction pressure (destruction condition - σ ≥ σв):

ΔP = 2d σв/ r, (2)

where σв is the temporary fracture resistance of the material, Pa.

Pressure of the vapor-gas mixture in the container:

Р = ΔP + Р0, (3)

where Р0 – Atmosphere pressure, 0.1·106 Pa.

Isentropic equation:

Р/Р0 = (ρ/ρ0)γ, (4)

where γ is the gas adiabatic index;

ρ0 – gas density at atmospheric pressure, kg/m3,

ρ – gas density at pressure in the container, kg/m3.

The gas density at pressure in the container is determined after transforming the isentropic equation (4):

ρ = ρ0 (Р/Р0)1/γ, (5)

Total gas mass:

С = ρ V, (6)

where V is the volume of the vapor-gas mixture, m3.

When a container explodes under internal pressure P of an inert gas (gas mixture) specific energy Gas Q:

Q= ΔP/[ρ (γ - 1)] (7)

In case of compressed explosive gas:

Q = Qв + ΔP/[ ρ (γ - 1)], (8)

where Qв is the specific explosion energy of the gas mixture, J/kg.

The TNT equivalent of a gas container explosion will be:

qtnt = Q C/ Qtnt, (9)

where Qtnt is the specific energy of the TNT explosion, equal to 4.24·106 J/kg.

The shock wave equivalent is estimated with a factor of 0.6:

qу. V. = 0.6 qtnt (10)

q = 2 · qу. V. (eleven)

Excess pressure at the shock wave front (ΔРfr, MPa) at a distance R is determined by the formula for a spherical air blast in free space:

where , R – distance from the epicenter of the explosion to the recipient, m.

Table 2 presents the values of the maximum permissible excess pressure of a shock wave during the combustion of gas, steam or dust-air mixtures in a room or open space, for which distances are selected to determine the affected areas.

Table 2 - Maximum permissible excess pressure during combustion of gas, steam or dust-air mixtures in a room or open space

Degree of damage	Excess pressure, kPa
Complete destruction of buildings (fatal injury to a person)
50% destruction of buildings
Average damage to buildings
Moderate damage to buildings (damage to internal partitions, frames, doors, etc.)
Lower threshold for damage to a person by a wave pressure
Minor damage (part of the glazing is broken)

Pressure wave impulse, kPa s:

Formulas (12.13) are valid under the condition ≥0.25.

The conditional probability of injury to a person located at a certain distance from the epicenter of the accident by the excess pressure developed during the explosion of steam-gas mixtures is determined using the “probit function” Pr, which is calculated by the formula:

Pr = 5 – 0.26 ln(V) , (14)

Where

The relationship between the Pr function and the probability P of one or another degree of damage is found in Table 3.

Table 3 – Relationship between the probability of defeat and the probit function

The main purpose of calculations using this method is to determine the radii of zones of varying degrees of airborne damage to buildings, structures and people and to determine the probability of injury to people located at a certain distance from the epicenter of the explosion.

Examples of calculations

Physical explosions

Example No. 1

The explosion of a spherical compressed air gas tank with a volume of V = 600 m3 occurred due to exceeding the regulated pressure. The device is designed to operate under pressure P = 0.8 MPa. The explosion occurred at a pressure P = 2.3 MPa. Gas density at normal pressure ρ = 1.22 kg/m3, adiabatic index γ = 1.4. Assess the consequences of a compressed air explosion in a spherical gas tank (determine the radii of zones of varying degrees of airborne damage to buildings, structures and people) and determine the probability of injury to a person at a distance R = 50 m.

Solution:

The pressure drop is determined by transforming formula (3):

ΔР = 2.3 - 0.1 = 2.2 MPa

The gas density is calculated using equation (5):

ρ = 1.22 · (2.3/0.1)1/1.4 = 11.46 kg/m3

Total gas mass:

C = 11.46 600 = 6873 kg

Q = 2.2 / = 0.48 MJ/kg

qtnt = 0.48 6873 / 4.24 = 778 kg

Shock wave equivalent:

qу. V. = 0.6 778 = 467 kg

In relation to a ground explosion, the following value is taken:

q = 2 467 = 934 kg

The calculation results are shown below (Table 4).

Table 4 – Radiuses of air blast impact zones

ΔРfr, kPa

To determine the probability of injury to a person at a given distance, the excess pressure in the wave front and the specific impulse for a distance of 50 m are calculated using formulas (12.13):

50/(9341/3) = 5,12

ΔРfr = 0.084/5.12 + 0.27/5.122 + 0.7/5.123 = 31.9 kPa.

I = 0.4 9342/3/50 = 0.76 kPa s

The conditional probability of being injured by excess pressure of a person located 50 m from the epicenter of the accident is determined using the probit function Pr, which is calculated using formula (14):

V = (17500/(31.9 103))8.4 + (290/(0.79 103))9.3 = 0.0065

Pr = 5 - 0.26 ln(0.0065) = 6.31

Using Table 3, the probability is determined. A person located at a distance of 50 m can receive injuries of varying severity with a probability of 91%.

Example No. 2

The explosion of a spherical carbon dioxide gas tank with a volume of V = 500 m3 (sphere radius 4.95 m) occurred due to excess of the regulated pressure. The device is made of steel 09G2S with a wall thickness of 16 mm and is designed to operate under pressure P = 0.8 MPa. Temporary fracture resistance of the material σв = 470 MPa. Gas density at normal pressure ρ = 1.98 kg/m3, adiabatic index γ = 1.3. Assess the consequences of an explosion of compressed carbon dioxide in a spherical gas tank (determine the radii of zones of varying degrees of airborne damage to buildings, structures and people) and determine the probability of injury to a person at a distance R = 120 m.

Solution:

Breaking pressure is determined by formula (2):

ΔP = 2 0.016 470/4.95 = 3 MPa

The pressure of the vapor-gas mixture in the container is determined by formula (3):

P = 3 + 0.1 = 3.1 MPa

The gas density is calculated using equation (5) at pressure P:

ρ = 1.98 · (3.1/0.1)1/1.3 = 28.05 kg/m3

Total gas mass:

C = 28.05 550 = 14026 kg

Using formula (7), the specific energy of the gas is calculated:

Q = 3 / = 0.36 MJ/kg

The TNT equivalent of a gas explosion will be:

qtnt = 0.36 14026 / 4.24 = 1194 kg

Shock wave equivalent:

qу. V. = 0.6 1194 = 717 kg

In relation to a ground explosion, the following value is taken:

q = 2 717 = 1433 kg

By selecting the distance from the epicenter of the explosion using formulas (12,13), the radii of zones of varying degrees of airborne damage to buildings, structures and people are determined, indicated in Table 2.

The calculation results are shown below (Table 5).

Table 5 – Radiuses of air blast impact zones

ΔРfr, kPa

To determine the probability of injury to a person at a given distance, the excess pressure in the wave front and the specific impulse for a distance of 120 m are calculated using formulas (12.13):

120/(14333) = 10,64

ΔРfr = 0.084/10.64 + 0.27/10.642 + 0.7/10.643 = 10.9 kPa.

I = 0.4 14332/3/120 = 0.42 kPa s

The conditional probability of being injured by excess pressure of a person located 120 m from the epicenter of the accident is determined using the probit function Pr, which is calculated using formula (14):

V = (17500/(10.9*103))8.4 + (290/(0.42*103))9.3 = 0.029

Pr = 5 - 0.26 * ln(0.029) = 5.92

Using Table 3, the probability is determined. A person located at a distance of 120 m can receive injuries of varying severity with a probability of 82%.

Chemical explosions

Example No. 1

Toluene was drained from a storage facility with a volume of V = 1000 m3 for repairs. At the beginning of welding, an explosion of toluene vapor occurred. Vapor density in air at normal pressure ρ = 3.2, adiabatic index γ = 1.4, VCPV - 7.8% vol., heat of gas explosion 41 MJ/kg. Assess the consequences of the explosion (determine the radii of zones of varying degrees of airborne damage to buildings, structures and people) and determine the probability of injury to a person at a distance R = 100 m.

Solution:

In the storage facility, the atmospheric pressure is P = 0.1 MPa.

Vapor Density:

ρ = 3.2 1.29 = 4.13 kg/m3

The volume of vapor is found through the VCPV (it is assumed that the entire volume is filled with a mixture with a concentration of toluene vapor corresponding to the VCPV):

V = 1000 7.8/100 = 78 m3

Total gas mass:

C = 4.13 78 = 322 kg

Using formula (8), the specific energy of the gas is calculated:

Q = 41 + 1/ = 41.06 MJ/kg

The TNT equivalent of the explosion will be:

qtnt = 41.06 322 / 4.24 = 3118 kg

Shock wave equivalent:

qу. V. = 0.6 3118 = 1871 kg

In relation to a ground explosion, the following value is taken:

q = 2 1871 = 3742 kg

The results of counting pressures and impulses are shown below (Table 6).

Table 6 – Radiuses of air blast impact zones

ΔРfr, kPa

To determine the probability of injury to a person at a given distance, the excess pressure in the wave front and the specific impulse for a distance of 100 m are calculated using formulas (12.13):

100/(37421/3) = 6,44

ΔРfr = 0.084/6.44 + 0.27/6.442 + 0.7/6.443 = 22.2 kPa.

I = 0.4 37422/3/100 = 0.96 kPa s

The conditional probability of being injured by excess pressure of a person located 100 m from the epicenter of the accident is determined using the probit function Pr, which is calculated using formula (14):

V = (17500/(22.2 103))8.4 + (290/(0.96 103))9.3 = 0.14

Pr = 5 - 0.26 ln(0.14) = 5.51

Using Table 3, the probability is determined. A person located at a distance of 100 m can receive injuries of varying severity with a probability of 69%.

Example No. 2

The explosion of a railway tank with a volume of V = 60 m3, filled with 80% toluene, occurred as a result of a lightning strike. Gas density at normal pressure ρ = 4.13 kg/m3, adiabatic index γ = 1.4, VCPV - 7.8% vol., heat of gas explosion 41 MJ/kg. The pressure in the tank is P = 0.1 MPa. Assess the consequences of the explosion (determine the radii of zones of varying degrees of airborne damage to buildings, structures and people) and determine the probability of injury to a person at a distance R = 30 m.

Solution:

The gas volume is determined through the filling factor and the VCPV (it is assumed that the entire volume is filled with a mixture with a toluene vapor concentration corresponding to the VCPV):

V = 60 0.2 0.078 = 0.936 m3

Total gas mass:

C = 4.13 0.936 = 3.9 kg

Using formula (7), the specific energy of the gas is calculated:

Q = 41 + 0.9/ = 41.1 MJ/kg

The TNT equivalent of the explosion will be:

qtnt = 41.1 · 3.9 / 4.24 = 37.4 kg

Shock wave equivalent:

qу. V. = 0.6 · 37.4 = 22.4 kg

In relation to a ground explosion, the following value is taken:

q = 2 22.4 = 44.8 kg

The results of counting pressures and impulses are given below (Table 7).

Table 7 – Radiuses of air blast impact zones

ΔРfr, kPa

To determine the probability of injury to a person at a distance R, the excess pressure in the wave front and the specific impulse for a distance of 30 m are calculated using formulas (12.13):

30/(44,81/3) = 8,4

ΔРfr = 0.084/8.4 + 0.27/8.42 + 0.7/8.43 = 14.9 kPa.

I = 0.4 44.82/3/30 = 0.17 kPa s

The conditional probability of being injured by excess pressure of a person located 70 m from the epicenter of the accident is determined using the probit function Pr, which is calculated using formula (14):

V = (17500/(14.9 103))8.4 + (290/(0.17 103))9.3 = 161

Pr = 5 - 0.26 ln(161) = 3.7

Using Table 3, the probability is determined. A person located at a distance of 30 m can receive injuries of varying severity with a probability of 10%.

List of used literature

1. Chelyshev theory of explosion and combustion. Tutorial– M.: Ministry of Defense of the USSR, 1981. – 212 p.

2. Explosive phenomena. Evaluation and consequences: In 2 books. Book 1. Trans. from English/ – M.: Mir, 1986. – 319 p.

3. Beschastnov explosions. Assessment and prevention - M.: Chemistry, 1991. - 432 p.

5. http://www. Press Center. ru

6. Accidents and disasters. Prevention and mitigation of consequences. Tutorial. Book 2. and others - M.: Publishing house. DIA, 1996. – 384 p.

7. GOST R 12.3.047-98 SSBT. Fire safety of technological processes. General requirements. Control methods.

8. RD Methodology for assessing the consequences of emergency explosions of fuel-air mixtures.

9. Fire and explosion hazard of substances and materials and means of extinguishing them/, etc. - M.: Khimiya, 1990. - 496 p.

10. Flammable and combustible liquids. Handbook/ed. -Agalakova – M.: Min. Publishing House. communal services, 1956. – 112 p.

11. , Noskov and tasks for the course of processes and apparatus of chemical technology. Textbook - L.: Chemistry, 1987. - 576 p.

12. Berezhkovsky and transportation of chemical products. – L.: Chemistry, 1982. – 253 p.

13. , Kondratiev safe devices for chemical and petrochemical industries. – L.: Mechanical engineering. Leningr. Department, 1988. – 303 p.

14. Metalist's Handbook. In 5 volumes. T. 2. Ed. , – M.: Mashinostroenie, 1976. – 720 p.

Applications

Appendix A

Table A1 - Properties of gases and some liquids

Name	The density of the substance, kg/m3 (at 20 оС)	Density by to air gas (steam)*	Adiabatic coefficient


Acetylene




Nitrogen dioxide
Carbon dioxide
Oxygen



Propylene

Note: Air density at 0°C is used to determine vapor density.

Appendix B

Table B1 - Construction materials

Material	Tensile strength, σin MPa	Purpose
St3ps, St3sp (gr. A)		For machine parts, machine tools, tanks.
		For storing diluted nitric and sulfuric acid, ammonium nitrate solution and similar substances with a density of 1400 kg/m3.
		For storing aggressive chemical products with a density of 1540 kg/m3.
		In the manufacture of pipelines and apparatus. Tanks for storing liquefied gases, railway tanks.


		Pipelines, pressure up to 100 kgf/cm2.
		Northern version for machine parts.

Home > Law

production of explosives and containing their products 1. The equipment must be designed taking into account the physicochemical and explosive properties of explosives and products intended for use: sensitivity to impact and friction, exposure to positive and negative temperatures, chemical activity and the ability to form new products, electrification, tendency to dust, caking, delamination, suitability for pneumatic transportation or pumping through pipes and other properties that directly or indirectly affect the safety of the “explosive - equipment” system. 2. The design of the equipment must ensure the safety of operating personnel, as well as technical characteristics and operating modes that comply with the requirements of regulatory and technical documentation for explosives and products intended for use, including: the possibility of free access for inspection and cleaning of units where explosives and products are exposed to mechanical stress, as well as to places where there may be accumulation of residues of explosives, lubricants and other products; limiting mechanical loads on explosives and products to safe limits; protection of hoses, grounding conductors of pipelines, rods, electrical wiring from abrasion during operation; compliance with the parameters of the specified thermal regime, incl. elimination of overheating in components and parts in contact with explosives and products, and, if necessary, temperature control; dosage of explosive components; installed dust suppression; blocking from dangerous violation of the sequence of operations; remote control of hazardous operations; reliable and timely control of ongoing technological processes; reliable light and (or) sound alarms about the occurrence or approach of dangerous (emergency) conditions. 3. When choosing materials for the manufacture of vessels and apparatus, take into account the wall temperature (minimum negative and maximum calculated), chemical composition, nature of the environment (corrosive, explosive, fire hazardous, etc.) and technological properties of substances. Materials should not enter into interaction with the reaction mass, vapors or dust of the substances being processed. 4. For the manufacture of individual parts, heat-resistant electrically conductive plastics of sufficient strength can be used. 5. Assemblies with rubbing and impacting parts that do not have direct contact with explosives and products, but are made of materials that produce sparks, must be reliably isolated from explosives and products or covered with plastic, or hermetically sealed with a casing made of materials that do not produce sparks . 6. In all cases, unless this is determined by specially regulated operating conditions of the units, the design of the equipment must prevent explosives from entering the gaps between rubbing and colliding parts. The latter can be achieved by using appropriate seals, remote bearings, breaker turns on augers and similar solutions. 7. There should be no fasteners (bolts, studs, dowels, pins, cotter pins) in the explosive passage paths. 8. In threaded connections outside the explosive passage path, it is necessary to provide a cotter pin or another method of fixing fasteners. 9. Equipment in which explosives capable of decomposition when left in a vessel or apparatus for a long time are produced or processed must not have stagnant zones where accumulation of substances is possible. 10. The design of equipment components must exclude the possibility of lubricants entering the explosive. 11. When operating the equipment, the heating of the surfaces of components and parts on which explosive dust can settle should not exceed 60 o C. This must be ensured by selecting appropriate operating modes and only in exceptional cases (pipelines and jackets with hot water , exhaust pipes of internal combustion engines, heaters, heat exchangers) through the use of thermal insulation. 12. The outer surfaces of vessels and apparatus having a temperature of more than 45 o C must have thermal insulation. Thermal insulation is fastened at the installation site, for which purpose devices for fastening the thermal insulation must be provided in the design of vessels and apparatus. Thermal insulation materials must be fireproof and not interact with processed substances. Vessels and apparatus must have devices that prevent explosives from entering between the thermal insulation and their outer surface. 13. The lubricants used must be indicated in the passport (form) for the equipment and in the relevant operational documentation approved in the prescribed manner. 14. The design of vessels and apparatus must exclude, in all intended operating modes, the possibility of loads appearing in parts and assembly units that could cause their destruction, which poses a danger to workers. 15. The design of vessels and apparatus and their individual parts must exclude the possibility of them falling or tipping over under all intended operating and installation (dismantling) conditions. 16. Design of clamping, gripping, lifting, loading, etc. devices or their drives must exclude the possibility of danger arising in the event of a complete or partial spontaneous interruption of the power supply, and also exclude a spontaneous change in the state of these devices when the power supply is restored. 17. Structural elements of vessels and apparatus should not have sharp corners, edges, burrs and other surfaces with irregularities that pose a risk of injury to workers, unless their presence is determined by the functional purpose of these elements. 18. Parts of equipment, including pipelines of steam, hydraulic, pneumatic systems, safety valves, cables, etc., the mechanical damage of which may cause danger, must be protected by fences or located so as to prevent their accidental damage by workers or maintenance means. 19. The design of vessels and apparatus must prevent spontaneous loosening or disconnection of fastenings of assembly units and parts, and also exclude the movement of moving parts beyond the limits provided for by the design, if this may lead to the creation of a dangerous situation. 20. In the design of the equipment, pneumatic, hydraulic, explosion-proof electric and mechanical drives can be used. 21. Taking into account the purpose, the design of the equipment and the operating procedures regulated in the operational documentation must exclude: the entry of foreign objects and substances into explosives and products, as well as atmospheric precipitation; damage to electrical wires, detonating cords, waveguides and other means of initiation during the loading process. 22. Covers and screens made of steel, which are removed during operation, at the joints with the frame of the bunker hatch must be reinforced with a material that softens the impact and does not produce sparks (rubber, elastic plastic), with measures taken to protect against the accumulation of potentials static electricity . 23. In order to prevent foreign objects from entering the explosive passage path, nets must be installed on loading hatches and container openings. The mesh cell sizes should not exceed 15x15 mm for grammonites, granulotol, alumotol, 10x10 mm for other explosives and ammonium nitrate, and in cases of perforated (round) holes, respectively, diameters: 18 and 12 mm. To avoid the formation of plugs during pneumatic charging, it is necessary to comply with the condition that the size of the sieve cells is no more than 1/2 the diameter of the nominal diameter of the charging pipeline. 24. The design of the equipment must prevent materials from hanging in bins, chambers and other storage and transfer units. If it is impossible to fulfill this requirement, the equipment must be equipped with effective and safe means for eliminating or preventing explosive hang-ups. 25. In screw conveyors, the possibility of pressing explosives or their components into the end parts of the screws, getting products into the bearings and friction of the screw screw against the inner walls of the casing must be excluded. To prevent explosives from being pressed into the end parts of the auger, the screw-screw design must provide for cutting off the explosive flow by using breaker turns at the end of the auger. In all cases, the length of the screws should be taken such that friction of its ribs on the casing, including due to deflection, is excluded. 26. Vibrating feeders may be used only for explosives that do not delaminate when exposed to vibration. 27. To move liquid components and flowing explosives along equipment paths, it is allowed to use hose and screw pumps.28. Belt conveyors for supplying explosives and products must be protected against slipping and equipped with a system that provides duplicate shutdown at any point along the length. The width of the conveyor belt must correspond to the design of the conveyor and be no more than one and a half width of a bag of explosives (ammonium nitrate). When transporting granular explosives in bulk, the width of the belt must be at least 3 times wider than the explosive pile on the belt. The design of belt conveyors must prevent explosives from getting onto the tension drums and support rollers, and also ensure that the conveyor belt is cleaned of adhering explosive particles by using special devices. Conveyors may only use belts made of flame-resistant materials that comply with current standards. 29. In cases where the shaft drives the executive bodies of grinding, mixing, transporting or dosing devices located in chambers or cavities where explosives may be located, the shaft bearings must be remote. The visible gap between the bearings and the wall separating the explosive path must be at least 40 mm. The installation of suspended bearings located inside the explosive flow is not allowed. Where the shaft passes through the wall separating the explosive movement path, it is necessary to place seals. 30. Remote bearings must be sealed by installing seals in the bearing caps. Gearboxes and bearing units must have a design that reliably protects against oil leakage and prevents the ingress of moisture, dirt and dust into them. 31. In all cases, cushioning and packing (sealing) materials must not come into contact with chemical reaction with explosives and their components. 32. Containers for flammable liquids on charging machines must have extinguishing partitions, vents or safety valves in the form of membranes designed to extrude the contents at a pressure of 0.05 MPa above the maximum permissible or a fusible element that collapses at a temperature of 110 -–115 o C. Safety valves should be located at the top of the container. Measures must be taken to protect the valves from any damage. 33. The degree of filling of containers for flammable flammable liquids and oxidizing solutions should not exceed 90% of their capacity. 34. To service loading hatches located at a height of more than 1.5 m from the floor level (platforms), it is necessary to provide working platforms equipped with climbing ladders, fences and handrails. 35. Before loading explosives and components into devices, measures must be taken to prevent the possibility of foreign objects getting into these devices (filtering liquid components, sifting or magnetic separation of bulk materials). The need to combine these control operations is determined by the directive technological process. The mesh sizes of sieves for sifting components must be specified in the technological process regulations. 36. All devices, equipment, components, parts, instruments, instruments and other items that have been in contact with explosives that have become unusable and are subject to further use or destruction must first be cleaned, washed and, if necessary, fired. 37. Equipment for production and preparation points for explosives and products used directly for the production and processing of explosives and products must comply with the requirements of design documentation developed in accordance with these regulations and the requirements of the relevant standards. 38. Changes in the design of the equipment in use are permitted only if there is appropriate design documentation approved in the manner established by the organization and agreed with the developer of this equipment. 39. For all equipment transferred into operation, passports (forms) must be drawn up, outlining the basic requirements for their operation. Imported equipment or equipment manufactured according to foreign licenses must ensure the safety requirements provided for by these technical regulations. Article 22. Requirements for means of transport mechanization technological, transport, loading and unloading and warehouse work

1. The main special requirements for lifting and transport machines and auxiliary devices used in explosion- and fire-hazardous premises and outdoor installations for working with explosive and fire-hazardous cargo must be:

Elimination of the impact of electrical sparks and discharges, sparks from friction and impact, heated surfaces on the explosive environment surrounding the equipment and the transported cargo;

exclusion of places inaccessible for cleaning in order to prevent stagnation, retention, crusting and pinching of the product;

the use of materials for the manufacture of structural elements of machines, taking into account the nature of the aggressive effects of transported substances, the characteristics of technological processes and safety requirements;

exclusion of interaction of the transported product with lubricants, working fluids of hydraulic systems, if such interaction leads to fire or explosion.

2. To perform lifting and transport operations in production, warehouse premises, loading and unloading areas, in railway cars with explosive and flammable substances contained in packaging, cases, boxes, the use of commercially produced lifting and transport machines and auxiliary devices is allowed general purpose subject to the requirements of Part 1 and the carrying capacity of which is greater than the nominal gross mass of the packaging of explosives and their products. 3. Load lifting mechanisms for lifting machines used for transporting explosives and flammable cargo must be equipped with two brakes and have a load rope safety factor of at least six.4. Explosive substances in a liquid state or in the form of a suspension should be transported, as a rule, by injection, as well as using diaphragm, membrane and other pumps specially designed for these purposes. 5. When transferring flammable substances and products by continuous transport from one room (building) to another room (building) isolated from it, automatic devices must be installed to prevent the spread of fire. 6. When transferring explosives from one building to another by continuous transport, the transfer of detonation along the transport chain between buildings, as well as the spread of flame in the event of fire, must be excluded. The use of pneumatic vacuum transport for transporting explosives between storage facilities and process buildings is not permitted. Conveyors transporting fire and explosive substances must have blocking devices that ensure stopping in the event of slipping, breakage of traction parts or jamming of the screw. Conveyors with inclined and vertical sections of the route must have safety devices that prevent spontaneous movement of the traction element or the transported cargo. 7. Operators who carry out local or remote control of the operation of hoisting and transport machines in explosion and fire hazardous areas must be provided with the possibility of evacuation. The movement control of lifting machines and mechanisms used to move explosive and fire hazardous cargo must be floor-based. Article 23 . Requirements for heat supply, water supply and sewerage 1. Heat and water supply to the production of explosives and products must be carried out taking into account the provision of technological needs, trouble-free shutdown of processes in the event of sudden restrictions on the supply of heat and water, and the needs for eliminating emergency situations. 2. The supply of steam to technological consumers of main production facilities should be carried out through two main pipelines with a calculated load of 70% of the total consumption for each. 3. Branches of heat pipelines from the mains must be made in two pipes to those buildings in which interruptions in the heat supply to technological consumers are not allowed due to safety conditions or loss of quality of products. 4. The introduction of heating networks into premises with explosive and fire hazardous, as well as corrosive materials is not allowed. Coolant inlets, heating points, water heating installations serving explosion- and fire-hazardous industries must be located in isolated rooms with independent entrances from the outside, from local cells or from safe corridors. It is allowed to place heating units and water heating units in the premises of supply ventilation chambers. For heating industrial premises in which explosive dust is emitted, air heating combined with forced ventilation, or water heating, or combined air-water heating with a temperature on the surface of heating devices not exceeding 80 o C should be used. 5. Building water supply network must provide the amount of maximum costs for the automatic fire extinguishing system, fire hydrants and external fire extinguishing. 6. The estimated water consumption for external fire extinguishing of buildings of categories A, Al, B, C, D is accepted to be at least 25 l/s. 7. The capacity of the fire-fighting water supply in the tanks of the enterprise’s water supply system is selected taking into account the operating time of automatic fire extinguishing systems according to Appendix 11. 8. Fire-fighting water supply to intermediate and base warehouses, industrial waste disposal sites located outside the enterprise’s territory is provided from fire tanks with a radius of action not more than 200 m or from hydrants located on the ring water supply network. In this case, one fire is taken into account, regardless of the area of the territory, with a water flow of 20 l/s.

9. Capacitive structures of the water supply system (reservoirs, receiving chambers) must be equipped with devices for water intake by fire trucks and have free entrances with a hard surface.

10. In order to save fresh water, the water supply of enterprises should be designed with a device closed systems for cooling purposes, as well as reuse systems for waste uncontaminated water and treated neutralized wastewater.

11. In addition to hydrants on the fire-fighting water supply network, it is also necessary to install hydrants on the chilled water supply networks of circulating systems running near explosion- and fire-hazardous buildings.

12. Industrial wastewater containing production products, as a rule, is discharged to local treatment facilities by an independent (industrial) sewerage system.

13. When disposing of industrial wastewater together with domestic wastewater through a combined sewerage system, subject to the possibility of their joint transportation and treatment, the content of contaminants in the wastewater should not exceed permissible concentrations for biological treatment facilities.

14. Wastewater containing nitroesters is discharged through an independent special network to a decomposition and neutralization unit. Neutralized wastewater is sent to biotreatment facilities together with the utility water of the enterprise. 15. Wastewater from the production of explosive explosives, production containing substances of the first hazard class, must be completely captured and neutralized directly in the building, after which they can be released into control well, and then into the sewer network. 16. The need for storm sewerage and storm water treatment is determined depending on the density of the territory, the nature of the road surface and the possible degree of pollution.

Article 24. Ventilation requirements

1. Explosive production facilities where harmful vapors, gases, and dust are released into the air must be equipped with ventilation devices, and ventilation must be carried out according to a system that prevents the possibility of transfer of fire from one room to another through air ducts and prevents the occurrence of fire in them.2 . At the stages of drying, sifting and capping explosives production, except for TNT, dinitronaphthalene and other insensitive to mechanical stress, exhaust ventilation should be carried out using ejectors. In the production of nitroethers and other liquid explosives, ballistic powders, explosives and mixtures based on them, as well as during equipment products with these substances, where, when gases and vapors are removed from the process equipment, condensate sensitive to mechanical stress can form, the ejecting air must be heated to a temperature that prevents condensation of vapors and gases. 3. Air removed by local suction, containing harmful explosive and fire hazardous substances, before being released into the atmosphere, must be cleaned to the permissible level of air pollution at the industrial site, as well as to the maximum permissible concentration in the air settlements. 4. Exhaust systems that remove explosive and fire-hazardous dust must be equipped with filters with water spray or others that prevent the release of dust into the atmosphere. The operation of the exhaust fan must be interlocked with the filter spray system, and, if necessary, with technological equipment. The filter must be installed upstream of the fan along the air flow. Filters can be installed both inside process rooms and in the exhaust ventilation chamber. 5. Explosion- and fire-hazardous industrial premises connected to each other by open, unprotected technological or doorways can be served by common ventilation systems. It is not allowed to release into one ventilation system vapors and gases, products, the interaction of which may create the danger of fire, explosion and equipment of harmful products. Explosion- and fire-hazardous premises that have independent external entrances that do not communicate with each other and are not connected by a single technological process must be served by independent ventilation systems for each room. 6. Disconnected explosion- and fire-hazardous industrial premises of the same technological process, located within the same floor, can be served by common supply ventilation systems of the collector type, subject to compliance following conditions: the total area of serviced premises should not exceed 1100 m2; each isolated room must be served by independent supply air ducts coming from the collectors; a self-closing check valve must be installed on each branch from the manifold within the ventilation plenum; collectors should be located within the premises intended for the installation of ventilation equipment (ventilation chambers), or outside the building. In some cases, it is permissible to place the collector in a safe room in a place accessible for servicing check valves; protection of transit air ducts laid through other premises must be ensured with a standardized fire resistance limit of at least 0.5 hours; the length of the air duct from the collector to the nearest air outlet must be at least 4 m; 7. The need for emergency ventilation and the amount of harmful substances released to calculate the air exchange in each special case determined by the directive technological process. Emergency ventilation must be turned on automatically and duplicated by manual activation outside the serviced room at the entrance to it. 8. Exhaust fans that move air mixed with explosive and fire hazardous substances must be designed to prevent the possibility of initiating a fire or explosion of the transported medium. 9. Supply fans serving industrial premises, where the technological process is associated with the release of solvent vapors, dust of explosive substances and compositions, can be accepted in the normal version made of carbon steel, provided that a self-closing check valve is installed on the air ducts after the fan and heaters, preventing the penetration into the fan, when it stops, and heaters of explosive and flammable substances from the premises. 10. Fans, as well as control devices installed on air ducts that remove air from production premises, if there is no release of explosive vapors or dust during the technological process, can be accepted in a normal design made of carbon steel. In exhaust systems with wet air cleaning that transport dust from ammonium perchlorate, potassium chlorate and ammonium nitrate, fans are accepted in the normal version made of acid-resistant steel, provided that the fans are installed after the filter. 11. If the production process in a bunded building is associated with the release of toxic gases, vapors and dust, the intake of outside air for supply systems must be carried out from the outside of the shaft. It is allowed to directly draw outside air from the space between the shaft and the building if all exhaust units are equipped with effective cleaning devices with a purification degree of at least 90%, while ventilation emissions must be made outside the circulation zone. 12. In technological air supply units, fans pumping air into technological devices that emit explosive vapors or dust must have a spark-proof design. It is allowed to use fans with increased protection against sparking. In cases where plate or fin heaters without a bypass duct are installed between the fan and the process apparatus, fans can be used made of carbon steel. In this case, after the heater along the air flow, a self-closing explosion-proof check valve must be installed within the ventilation chamber. Regulating and other elements within the production premises must be explosion-proof. 13. When suctioning the steam-air mixture of solvents for recovery in process rooms of category B, it is necessary to install oil strainers located upstream of the fire arrester along the flow of the steam-air mixture.14. Premises for equipment of exhaust systems must meet the fire and explosion safety requirements for the production premises they serve, depending on the category of production processes located in them. 15. Explosive warehouses are equipped with a natural exhaust ventilation system to prevent moisture condensation on the surface of the packaging.16. In workshops and individual workplaces where dust formation is possible, supply air must be distributed through air distributors with a rapid attenuation of speeds, eliminating the possibility of dust blowing.17. The internal surface of the ventilation system pipelines must be such that product dust does not linger on it, and so that it can be easily cleaned or rinsed from contamination. Ventilation units must have hatches in the air ducts for washing and cleaning the inner surface of the air ducts during general cleaning and before repairs, as well as hatches for checking actual performance and taking air samples for content chemical substances. Article 25. Electrical requirements and

Initial data for calculations. Tasks course work: - systematization, consolidation and expansion of theoretical and practical knowledge in these disciplines; - acquisition of practical skills and development of independence in solving engineering problems; - preparing students to work on further coursework and diploma projects DEVICE OF THE APPARATUS AND SELECTION OF CONSTRUCTION MATERIALS Description of the device and operating principle of the apparatus A reaction apparatus is a closed vessel designed for...

Share your work on social networks

If this work does not suit you, at the bottom of the page there is a list of similar works. You can also use the search button

Introduction ...................................................................................................................................

Device design and...............................
1. …………………………
2. ……
3. Selection of construction materials………………………………………..

Purpose of calculations and initial data……………………………………………………
1. Purpose of calculations ……………………………………………………………………
2. Design diagram of the apparatus……………………………………………………..
3. Initial data for calculations……………………………………………….
4. …………………………………………

Strength calculation of the main elements of the apparatus……………………………….
1. ………………………………………………
  1. Calculation of the wall thickness of the housing shell loaded with excess internal pressure……………………………………………………………..
  2. Calculation of the wall thickness of the housing shell loaded with external pressure
  3. Calculation of the jacket shell loaded with internal pressure
2. Bottom calculation ……………………………………………………………………..
  1. Calculation of the bottom of the hull loaded with excess internal pressure…………………………………………………………………………….
  2. Calculation of the wall thickness of the hull bottom loaded with external pressure…………………………………………………………………………….
  3. Calculation of the bottom of a jacket loaded with excess internal pressure…………………………………………………………………………….
3. ………………………………………………..
4. ………………………...
5. Selection and calculation of support…………………………………………………………...

conclusions ………………………………………………………………………………………..

Bibliography.......................................................................................

INTRODUCTION

Modern chemical production with specific equipment operating conditions, often characterized by high operating parameters (temperature and pressure) and generally high productivity, requires the creation of high-quality devices.

The high quality of the devices is characterized by: high efficiency; durability (service life of at least 15 years); efficiency; reliability; security; convenience and ease of maintenance, depending on both quality and workmanship.

Coursework objectives:

Systematization, consolidation and expansion of theoretical and practical knowledge in these disciplines;

Acquisition of practical skills and development of independence in solving engineering problems;

Preparing students to work on further coursework and diploma projects

DEVICE CONSTRUCTION AND SELECTION OF CONSTRUCTION MATERIALS

Description of the device and operating principle of the device

A reaction apparatus is a closed vessel designed to carry out various physical and chemical processes. Reactor apparatus in which the main process of chemical technology takes place; it must work efficiently, i.e. provide a certain depth and selectivity of the chemical transformation of substances. The reactor must meet the following requirements: have the required reaction volume; ensure the specified productivity and hydrodynamic mode of movement of reacting substances, create the required phase contact surface, maintain the necessary heat exchange, level of catalyst activity, etc.

The design of the reaction apparatus is determined by a number of factors: temperature, pressure, required heat exchange intensity, consistency of the materials being processed, state of aggregation materials, etc.

On the lid and body of the device there are two pipes for supplying and discharging products. Using a stirrer, the substances are mixed. To maintain a certain temperature inside the reactor, the apparatus is equipped with a jacket, on which there are two pipes for supplying a heating agent and discharging condensate.

Selecting the design of the main elements of the device

The elements to be selected and designed are: shell (body), bottom, cover, jacket, stirrer, flange connections, supports.

We select the design of the main elements of the device in accordance with the use.

For steel cylindrical shells, the shells of which are made of rolled sheets, GOST 9617-76 is used.

We choose the bottom of an elliptical shape with a flange on the cylinder (GOST 6533-78) [page 112, Fig. 7.1(a), 1]. The dimensions of the hull bottom are taken according to Table 7.2 p. 116:

; ; .

The covers of the devices can be either detachable or entirely welded with the device. Such all-welded devices are usually equipped with hatches, which are standardized. The design of the hatch with a cover is accepted with a spherical cover, version 1 with a seal on the connecting ledge.

The jackets are designed for external heating or cooling of liquid products processed and stored in the apparatus. By design, shirts are either one-piece or detachable. One-piece shirts are simpler and more reliable in operation. Therefore, we accept a steel one-piece jacket for a steel vertical apparatus of type 1 with an elliptical bottom and lower product outlet p. 164:

; ; ; .

Designation: Shirt 1-3000-3563-2-О OST 26-01-984-74.

Jackets with elliptical bottoms are used at and, which corresponds to the specified conditions in the jacket (,).

In devices for detachable connection of composite housings and individual parts, flange connections are used, mainly round in shape. The design of the flange connection is used depending on the operating parameters of the device. When and use flat welded flanges .

The design of the mixer is an open turbine one. Turbine mixers provide intensive mixing throughout the entire working volume of the mixer when mixing liquids with a viscosity of up to, as well as coarse suspensions.

Installation of devices on foundations or special supporting structures is carried out for the most part using supports. Vertical devices are usually installed on suspended legs, when the device is placed between floors in a room or on special structures. We accept the design of supports paws.

Selection of construction materials

When choosing construction materials, you must consider:

Operating conditions of the device, i.e. corrosive and erosive properties of the medium, temperature and pressure of the medium;

Technological properties of the material used: weldability, ductility and others;

Technical and economic considerations

For the body of the device we choose steel 12Х18Н10Т GOST 5632-72. Steel 12Х18Н10Т is a high-alloy, corrosion-resistant steel of the austenitic class. This steel is very common in the chemical industry and is not in short supply. Steel will not affect the liquid medium located in the body of the device.

According to the condition, the shirt contains a non-aggressive environment (water vapor). Taking this into account, for the shirt we choose carbon steel of ordinary quality VSt3sp5 GOST 380-71.

The stirrer and shaft, which come into contact with the working medium, are made of steel with corrosion resistance no lower than the steel from which the apparatus body is made. We also choose steel 12Х18Н10Т GOST 5632-72.

Since the device contains a non-toxic and non-explosive environment, and the operating pressure does not exceed this value, gland seals are used.

The workpiece material or finished fasteners must be heat treated. The mating nuts and bolts (studs) must be made of materials of different hardness, with the bolts (studs) being preferably harder. According to the material of the fasteners, we select St. 35 GOST 1050-74 HB=229 (bolts) and HB=187 (nuts).

We select the gasket material GOST 480-80 paronite.

Straight and circular butt welds of the apparatus, made of sheet steel, are performed by semi-automatic submerged arc welding. We select welding materials used for semi-automatic welding:

for high-alloy steel 12Х18Н10Т:

Wire grade 05Х20Н9ФБС GOST 2246-70

for carbon steel VSt3sp5:

Wire grade SV-08A GOST 2246-70

Flux grade OSTS-45 GOST 9087-69

for high-alloy steel 12Х18Н10Т with carbon VSt3sp5:

Wire grade 07Х25Н12Г2Т GOST 2246-70

Flux grade AN-26S GOST 9087-69

In the manufacture and welding of internal devices of the apparatus and supporting structures, manual electric arc welding is used. We select the following welding materials:

1) for fittings made of high-alloy steel 12Х18Н10Т, with a body:

Electrode type E08Х20Н9Г2Б GOST 10052-75;

2) for fittings and supports made of carbon steel VSt3sp5, with a jacket:

Electrode type E50A GOST 9467-75.

PURPOSE OF CALCULATIONS AND INITIAL DATA
1. Purpose of calculations

The purpose of the work is:

Determination of the thickness of the shell walls, hull bottoms and jackets;

Determination of the main dimensions of the reinforcing elements of the holes;

Selecting a flange connection, determining the diameter and number of bolts of the flange connection;

Selection and calculation of support

Design diagram of the apparatus

Mixer design for liquid media with a mixing device is shown in Figure 1. In accordance with Figure 1, the main elements of the mixer are: a housing with a jacket, a cover, a drive with a stand, a rotating mixer mounted on the shaft, an stuffing box and mechanical seal, a fitting for discharging reaction products.

Rice. 1 Design diagram of the device.

Initial data for calculations

Initial data:

Apparatus volume

In the reactor
Wednesday	Temperature, C	Pressure, MPa
Glycerin, 30%
In a shirt
Wednesday	Temperature, C	Pressure, MPa
Steam		0,33

Diameter values

Drive weight

Place the supports on the wall of the shirt;

The drive in the drawing is shown conventionally. Take drive height equal height reactor.

Determination of design parameters

The design temperature is determined based on thermal calculation or test results. If it is impossible to perform a thermal calculation, the design temperature is equal to the operating temperature, but not less than 20 0 C, therefore:

Operating temperature: housing

Shirts

Design temperature: housings

Shirts

The design pressure for the apparatus body is taken equal to:

(2.1)

Let's check the need to take into account the pressure of the hydrostatic liquid column by checking the condition:

; (2.2)

; (2.3)

where is the density of the medium in the housing at operating temperature. The medium in the housing is a 30% glycerin solution. The density of the solution is determined by the formula:

; (2.4)

where W humidity, accept W =90%;

T=275 295 0 K, take T=290 0 K;

The height of the liquid level in the device body;

The condition is met, therefore, the pressure of the hydrostatic column of liquid in the apparatus must be taken into account. Then the design pressure is determined by the formula:

; (2.5)

We select the permissible stresses of the housing material according to Table 1.4 at the design temperature

We select the permissible stresses of the jacket material according to Table 1.3 at the design temperature

Design pressure for jacket:

(2.6)

Let's check the need to take into account the hydrostatic column of liquid in the jacket. According to formula (2.3):

Then using formula (2.2) we obtain:

Since the condition is not met, the pressure of the hydrostatic column of liquid in the apparatus is not taken into account. Hence.

The test pressure during hydraulic testing of the housing is determined by the formula at:

; (2.7)

The test pressure during hydraulic testing of the jacket is determined by the formula when:

; (2.8)

Allowable stresses during hydraulic testing are determined by the formula:

; (2.9)

where is a correction factor taking into account the type of workpiece. For rolled steel sheets

Yield strength of steel at 20 0 C. For steel 12Х18Н10Т; for steel VSt3sp5;

For body material;

For shirt material.

Let's check the need to calculate the device for internal test pressure by checking the condition:

; (2.10)

where - hydrotest pressure is determined by the formula:

; (2.11)

where is the density of water at;

The height of the liquid column (water);

Using formula (2.10) we obtain:

The condition is not met, therefore, a calculation of the strength of the apparatus body under hydrotest conditions is required.

We check condition (2.10) for the shirt:

where is the height of the water level in the jacket during hydrotesting;

Using formula (2.10) we obtain:

The condition is not met, therefore, a calculation of the strength of the apparatus jacket under hydrotest conditions is required.

STRENGTH CALCULATION OF MAIN ELEMENTS OF DEVICES

Calculation of cylindrical shells

Let's start by calculating the cylindrical shell of the body.

There are two pressures acting on the shell: excess internal (inside the reactor) and external pressure (pressure in the jacket), thus, when calculating the cylindrical shell of the housing, there will be two thickness options, from which the maximum must be selected.

The volume occupied by the shell is determined as the difference between the volume of the apparatus and the volume of the bottom:

; (3.1)

Shell height:

; (3.2)

Estimated length of the cylindrical shell of the body:

; (3.3)

where is the length of the shell, which is subject to external pressure;

The height of the cylindrical part of the mating bottom is taken according to page 118;

Height of the elliptical part of the bottom;

3.1.1 Calculation of the wall thickness of the housing shell loaded with excess internal pressure

We determine the estimated thickness of the shell shell, the calculation is carried out using and:

; (3.4)

where is internal pressure;

Shell diameter;

Design shell thickness for hydrotest conditions:

; (3.5)

Checking the condition:

; (3.6)

The condition is not met, therefore.

The effective wall thickness is determined by the formula:

; (3.7)

where with the total amount of increase to the calculated wall thicknesses. Magnitude With determined by the formula:

; (3.8)

where c 1 increase to compensate for corrosion and erosion;

C 2 increase to compensate for minus tolerance;

C 2 technological increase;

Increase from 1 determined by the formula:

; (3.9)

where is the corrosion rate of the body material steel 12Х18Н10Т

T=20 years service life of the device;

values c 2, c 3 are equal to zero.

Using formula (3.7) we obtain:

Select the nearest higher standard value.

3.1.2 Calculation of the wall thickness of the housing shell loaded with external pressure

The approximate wall thickness is determined by the formula:

; (3.10)

where is the coefficient determined according to Fig. 6.3 depending on the values of the coefficients and:

; (3.11)

where is the stability safety factor for operating conditions, taken in accordance with p. 105;

The stability factor for hydrotest conditions is taken in accordance with page 105;

Modulus of elasticity for steel 12Х18Н10Т;

Modulus of elasticity for steel VSt3sp5;

The calculated external pressure is assumed to be equal to the water pressure in the jacket;

for working conditions: ;

for hydrotesting: .

Calculated coefficient K 3 determined by the formula:

; (3.12)

We define: for working conditions

For hydrotest conditions.

According to formula (3.10) for operating conditions:

For hydrotest conditions:

The calculated wall thickness of the housing shell, loaded with internal and external pressure, is taken from the maximum condition:

; (3.13)

; (3.14)

Axial compressive force F determined by the formula:

for working conditions; (3.15)

for hydrotest conditions (3.16)

Let's check the stability of the housing shell. The following condition must be met:

for working conditions; (3.17)

for hydrotest conditions; (3.18)

where and is the pressure under operating conditions and hydrotesting, respectively;

I - permissible external pressure under operating conditions and under hydrotest conditions;

I is the permissible axial compressive force under operating conditions and under hydrotest conditions;

Permissible external pressure based on strength conditions:

In working conditions; (3.19)

under hydrotest conditions; (3.20)

In working conditions; (3.21)

where B 1 is defined as follows:

; (3.22)

we take B 1 =1;

Under hydrotest conditions (3.23)

Permissible external pressure taking into account strength and stability:

In working conditions; (3.24)

Under hydrotest conditions; (3.25)

Let's check the shell strength condition:

In working conditions; (3.26)

Under hydrotest conditions; (3.27)

The strength conditions are met.

Allowable axial compressive force based on strength conditions:

For working conditions; (3.28)

for hydrotest conditions; (3.29)

Allowable axial compressive force from the condition of stability within the limits of elasticity at; (3.30)

; (3.31)

For working conditions;

for hydrotest conditions.

Allowable axial compressive force taking into account both conditions:

For working conditions; (3.32)

for hydrotest conditions; (3.33)

We check condition (3.17):

We check condition (3.18):

Both stability conditions are met.

3.1.3 Calculation of the jacket shell loaded with internal pressure

The calculated thickness of the jacket shell is determined by the formula:

; (3.34)

where is the pressure in the jacket;

Shirt diameter;

Weld strength coefficient for butt welds of a jacket with double-sided continuous penetration, performed by automatic welding;

For hydrotest conditions:

; (3.35)

As the design thickness

Performance wall thickness:

; (3.36)

where c is determined by the formula:

; (3.37)

where is the corrosion rate of the body material steel VSt3sp5

We accept a larger standard value.

For working conditions; (3.38)

for hydrotest conditions; (3.39)

Checking the strength condition

For working conditions; (3.40)

For hydrotest conditions; (3.41)

Bottom calculation

We begin the calculation from the bottom of the hull. It is subject to two pressures: external and internal excess.

3.2.1 Calculation of the bottom of the hull loaded with excess internal pressure

In working conditions; (3.42)

where is internal pressure;

Bottom diameter;

Permissible stresses for steel 12Х18Н10Т at;

The strength coefficient of the weld seam in automatic electric arc welding is taken according to;

under hydrotest conditions; (3.43)

Of the two values, choose the larger one, i.e. .

3.2.2 Calculation of the wall thickness of the hull bottom loaded with external pressure

The wall thickness of the elliptical bottom is calculated by the formula:

In working conditions; (3.44)

where K E coefficient of reduction of the radius of curvature of the elliptical bottom. For preliminary calculation we take K E =0.9;

In working conditions

or;

for hydrotest conditions; (3.45)

or;

The calculated wall thickness of the hull bottom, loaded with excess internal and external pressure, is taken from the condition:

; (3.46)

8.5mm.

Performance wall thickness:

; (3.47)

We accept a larger standard value.

Allowable internal overpressure:

; (3.48)

Let's check the strength condition:

; (3.49)

The permissible external pressure is determined by the formula:

For working conditions; (3.50)

Permissible pressure based on strength conditions:

; (3.51)

Allowable pressure from the stability condition:

; (3.52)

Coefficient K E determined by the formula:

; (3.53)

; (3.54)

For hydrotest conditions; (3.55)

; (3.56)

Allowable pressure from the stability condition:

; (3.57)

Checking the strength condition

For working conditions; (3.58)

For hydrotest conditions; (3.59)

Both strength conditions are met.

3.2.3 Calculation of the bottom of a jacket loaded with excess internal pressure

The calculated wall thickness of the elliptical bottom is determined by the formula:

In working conditions; (3.60)

where is internal pressure;

Shirt diameter;

Allowable stresses for steel VSt3sp5 at;

The strength coefficient of the weld seam in automatic electric arc welding is taken according to;

under hydrotest conditions; (3.61)

Of the two values, choose the larger one, i.e. .

Performance wall thickness:

; (3.62)

We accept a larger standard value.

Allowable internal overpressure:

For working conditions; (3.63)

for hydrotest conditions; (3.64)

Checking the strength condition

For working conditions; (3.65)

For hydrotest conditions; (3.66)

Both strength conditions are met.

Calculation and strengthening of holes

Let's calculate a hole that does not require reinforcement:

; (3.67)

Where; (3.68)

; (3.69)

We check the condition: ; (3.70)

The condition is met, therefore, this hole should not be strengthened. This also applies to the other holes.

Selecting a flange connection and calculating its bolts

Material of bolts, nuts steel 35 GOST 1050-74;

Flange material 20K;

Gasket material paronite GOST 480-80;

Design pressure inside the apparatus 0.136 MPa;

Design temperature -

Inner diameter of flange connection;

Wall thickness;

Main parameters of flange connection:

Flange inner diameter;

Flange outer diameter;

Bolt circle diameter;

Geometric dimensions of the sealing surface;

Flange thickness;

Diameter of holes for bolts;

Number of holes;

Bolt diameter;

Main gasket parameters:

Outside diameter;

Inner diameter;

Gasket width;

Load acting on the flange connection from excess internal pressure:

; (3.71)

where is the average diameter of the gasket;

; (3.72)

Gasket reaction under operating conditions:

; (3.73)

where is the effective width of the gasket;

for flat gaskets; (3.74)

The coefficient is taken according to ;

Force arising from temperature deformations. For weld-on flanges made of one material:

; (3.75)

where is the number of bolts;

; (3.76)

where is the bolt pitch;

; (3.77)

Dimensionless coefficient. For connections with weld-on flanges:

; (3.78)

Where; (3.79)

where is the linear compliance of the gasket;

(3.80)

where is the modulus of ultimate elasticity of the gasket material, taken according to ;

Linear compliance of bolts:

; (3.81)

where is the design length of the bolt:

; (3.82)

where is the length of the bolt between the supporting surfaces of the bolt head and the nut;

; (3.83)

- ;

The calculated cross-sectional area of the bolt along the internal diameter of the thread, ;

Modulus of longitudinal elasticity of the bolt material;

Angular compliance of the flange:

; (3.83)

where w dimensionless parameter;

Coefficient;

Dimensionless parameter;

Approximate flange thickness;

Modulus of longitudinal elasticity of the flange material;

; (3.84)

where is a dimensionless parameter;

; (3.85)

for flat weld flanges; ; (3.86)

We accept according to ;

; (3.87)

Where; (3.88)

Equivalent flange sleeve thickness for flat weld flanges;

Smaller thickness of the conical flange bushing;

But; (3.89)

We accept according to ;

Coefficient of thermal linear expansion of flange material;

Coefficient of thermal linear expansion of bolt material;

According to ;

; (3.90)

where is a parameter, we accept according to ;

Flange connection stiffness coefficient;

; (3.91)

Where; (3.92)

for flat weld flanges.

We accept according to ;

; (3.93)

Reduced bending moments in the diametric direction of the flange section:

; (3.94)

; (3.95)

; (3.96)

Bolt strength conditions:

; (3.97)

; (3.98)

; ;

; .

The torque on the wrench when tightening the bolts (studs) is determined by.

Gasket strength condition:

; (3.99)

; .

The gasket strength condition is met.

s 1 flange:

; (3.100)

at - we accept according to

Maximum stress in section s 0 flange:

; (3.101)

where - we accept according to ;

Stress in the flange ring due to torque M 0 :

; (3.102)

Stress in the flange sleeve due to internal pressure:

; (3.103)

; (3.104)

Flange strength condition:

; (3.105)

at; (3.106)

Flange rotation angle:

; (3.107)

for flat flanges ;

. (3.108)

Selection and calculation of support

The calculation is carried out according to .

We determine the design loads. The load on one support is determined by the formula:

; (3.109)

where, are coefficients depending on the number of supports;

P weight of the vessel under operating conditions and under hydrotest conditions;

M external bending moment;

D jacket diameter;

e distance between the force application point and the backing sheet.

Since the external bending moment equal to zero, then formula (3.109) takes the form:

; (3.110)

With the number of supports;

Weight of the vessel under operating conditions;

Weight of the vessel under hydrotest conditions;

for working conditions;

for hydrotest conditions;

Axial stress from internal pressure and bending moment:

; (3.111)

where is the wall thickness of the apparatus at the end of its service life;

; (3.112)

where s specific thickness of the apparatus wall;

C increase to compensate for corrosion;

C 1 additional increase;

for working conditions;

for hydrotest conditions.

Circumferential stress from internal pressure:

; (3.113)

for working conditions;

for hydrotest conditions.

Maximum membrane stress due to main loads and support reaction:

; (3.114)

for working conditions;

for hydrotest conditions.

The maximum membrane stress from the main loads and the support reaction is determined by the formula:

; (3.115)

[ 1, p. 293, fig. 14.8 ] ;

for working conditions;

for hydrotest conditions

Maximum bending stress from support reaction:

; (3.116)

where is a coefficient depending on the parameters and.[ 1, p. 293, fig. 14.9 ] ;

for working conditions;

for hydrotest conditions.

The strength condition has the form:

; (3.117)

where - for working conditions;

For hydrotest conditions;

for working conditions;

for hydrotest conditions;

The strength condition is met.

The thickness of the overlay sheet is determined by the formula:

where is the coefficient, we accept according to ;

for working conditions;

for hydrotest conditions;

We finally accept.

CONCLUSIONS

The result of the course design is a detailed calculation of the apparatus and its elements based on its operating conditions. In particular, the thickness of the shell, jacket, and bottom was calculated; flange connection calculation; calculation of strengthening holes; calculation of supports. Materials were also selected taking into account technical and economic indicators. Most of the thicknesses of the apparatus elements were taken with a margin based on strength calculations, which makes it possible to use the apparatus under more stringent conditions than those specified.

So, based on the calculations, we can conclude that the designed device is suitable for operation under the given conditions.

BIBLIOGRAPHY

1. Lashchinsky A.A. Design of welded chemical apparatus: Handbook. L.: Mechanical engineering. Leningr. department, 1981. 382 p., ill.

2. Mikhalev M.F. "Calculation and design of machines and apparatus for chemical production";

3. Lecture notes on CREO

Other similar works that may interest you.vshm>
5103.		Calculation of the heat exchanger	297.72 KB
	Determination of gas mixture parameters that are the same for all thermodynamic processes. In the main technological installations and devices of oil and gas industry The most common gases are hydrocarbons or their mixtures with air components and a small amount of impurities of other gases. The purpose of thermodynamic calculation is to determine the main parameters of the gas mixture in...
14301.		CALCULATION OF WATER SOFTENING DEVICE	843.24 KB
	The purpose of this course project is to calculate a water softening station with a capacity of 100 cubic meters. Calculation of a membrane apparatus consists of determining the required number of membrane elements, drawing up balance diagrams for the movement of water and components, selecting pumping equipment to ensure the required operating pressure when supplying water to the membrane apparatus, determining...
1621.		Calculation of drive elements (apparatus, device)	128.61 KB
	When completing a course project, the student sequentially goes from choosing a mechanism diagram through a variety of design solutions to its implementation in working drawings; getting involved in engineering creativity, mastering previous experience.
20650.		Strength calculation of the main elements of the apparatus	309.89 KB
	Initial data for calculations. Objectives of the course work: - systematization, consolidation and expansion of theoretical and practical knowledge in these disciplines; - acquisition of practical skills and development of independence in solving engineering problems; - preparing students to work on further coursework and diploma projects DEVICE OF THE APPARATUS AND SELECTION OF CONSTRUCTION MATERIALS Description of the device and operating principle of the apparatus A reaction apparatus is a closed vessel designed for...
6769.		Speech apparatus device	12.02 KB
	When breathing, a person's lungs compress and unclench. When the lungs are compressed, the air passes through the larynx, across which are located vocal cords in the form of elastic muscles. If an air stream comes from the lungs, and the vocal cords are moved and tense, then the cords vibrate - a musical sound (tone) appears.
13726.		Anatomy of the musculoskeletal system	46.36 KB
	The main place in the bone is occupied by: lamellar bone which forms compact substance and spongy bone. Chemical composition And physical properties bones. The surface of the bone is covered with periosteum. The periosteum is rich in nerves and blood vessels, through which nutrition and innervation of the bone is carried out.
20237.		Musculoskeletal disorders in children	156.13 KB
	Despite the fact that musculoskeletal system is, it would seem, the strongest structure of our body; in childhood it is the most vulnerable. It is in infancy and adolescence that pathologies such as torticollis, flat feet, scoliosis, kyphosis and other postural disorders are discovered. And if proper measures are not taken in time to eliminate congenital or emerging defects in the child
17394.		Analysis of the activity of the Golgi apparatus in the cell	81.7 KB
	The Golgi apparatus is a component of all eukaryotic cells(almost the only exception is mammalian red blood cells). It is the most important membrane organelle that controls intracellular transport processes. The main functions of the Golgi apparatus are modification, storage, sorting and direction various substances into the corresponding intracellular compartments, as well as outside the cell.
11043.		CALCULATION AND SELECTION OF LANDINGS OF TYPICAL CONNECTIONS. CALCULATION OF DIMENSIONAL CHAINS	2.41 MB
	The state of the modern domestic economy is determined by the level of development of industries that determine scientific and technical progress countries. Such industries primarily include the machine-building complex, which produces modern vehicles, construction, hoisting and transport, road machines and other equipment.
18482.		Design of a vertical type shell-and-tube heat exchanger	250.25 KB
	In the PSV heater, cold water from the network flows through the heat exchange pipes, at the same time, heating steam enters through the steam supply pipe into the internal interpipe space, where, in contact with the heat exchange pipes, it heats the water. The condensate formed during this process is discharged through a special pipe at the bottom of the housing.