A gas canister exploded. Why does propane explode? Stretch ceiling and explosion

Household gas has the same powerful destructive force as TNT! Using gas and neglecting safety measures, we expose our lives, the lives of loved ones and neighbors to mortal danger. How does a gas explosion occur? Take a closer look at the picture:

So why does gas explode? The main reason - improper storage and operation. Industrial defects account for a minimum of tragic cases, which, again, were provoked by operational violations.

For household gas to explode, it must mix with air. The most dangerous concentrations are 30 and 70 percent of gas. If you smell gas, something is wrong. In this case, the leak must be repaired immediately. At the same time, you should remember that you cannot use electricity (do not turn on or off the lights or other devices), you cannot use open fire, or smoke. At the same time, the room should be completely ventilated.

Typical situations in everyday life that lead to explosions:

• A boiling kettle/saucepan extinguishes the gas burner, but gas continues to flow intensively into the room. Accidental spark - explosion and fire.
• A cylinder that has been stored for a long time is brought out of the cold into a warm room or placed next to a heat source (the same gas stove). There is a sharp change in temperature, the cylinder bursts with internal pressure. A subsequent gas explosion is inevitable.
• A common misconception is that rupture of a pressure cylinder is possible only in the situation described earlier and only in winter. This is wrong. It is the large temperature difference that has an effect. If in summer you move the cylinder from a cool room to a hot kitchen, the effect will be the same.
• The rupture of the cylinder occurs due to microcracks that form over time. In the process of corrosion inside(!) the cylinder. If a steel cylinder is beautiful and new on the outside, this does not mean at all that it is in good condition inside. Shake the empty cylinder that contains no gas. Do you feel something rustling there? - this is condensation. It is this, like any moisture, that causes a gas cylinder to rust. Time passes and at one tragic moment the pressure will do its job (described above). This can happen even while filling a gas cylinder. Composite cylinders do not have this disadvantage - there is nothing there to rust.
• Gas leaking from a crack in a worn out, frayed hose. Leakage from the connection between the hose and the cylinder or stove. Gas gradually fills the room, then again any spark ignites the accumulated propane.

Many other cases can be written, but it's better to see once How does this happen. The surveillance video is impressive. Safety requirements were invented for a reason.

Main reasons for the explosion household gas cylinders are:

• Violation of norms and rules for refilling household cylinders
• Violation of the rules for storing and operating gas cylinders

According to standards Gas cylinders must be refilled at specialized stations, where they are filled strictly by weight on special weighing units. This filling of cylinders is carried out to a maximum of 85% of their volume. 15% - buffer zone, intended for the transition of part of the liquid phase into the gaseous phase.

According to statistics, the main share of explosions occurs in the cold season due to a large temperature difference between refueling and operation. However, the temperature difference itself cannot lead to an explosion, since these products have an operating temperature range from -40 to 50 degrees C, and the main reason is violation of the rules for operating gas vessels working under pressure. Such as:

• lack of timely examination (once every 5 years),
• refueling at non-specialized points, where refueling is carried out from a conventional gas dispenser, and the degree of filling is controlled by pressure,
• refilling cylinders with expired service life (40 years),
• placement of gas containers during storage and operation in common areas.

If the cylinders are not filled at a specialized station, then they are filled to capacity. If such refueling is carried out in the summer, then the temperature of the refueled gas is almost equal to the ambient air temperature. In winter refilling propane cylinders requires special adherence to temperature conditions.

If a cylinder is filled to capacity in the cold and then brought into a warm room, the pressure in it increases sharply, because LPG is characterized by a high coefficient of thermal expansion. If there is no buffer zone in a gas cylinder, the excess pressure has nowhere to go, and it begins to have a destructive effect on the walls of the cylinder and ultimately leads to explosions of gas cylinders in houses.

Gas leak through the valve causes gas to gradually fill the room. That is why, store gas cylinders necessary outdoors, in cabinets specially designed for this purpose, with holes for ventilation. Such storage does not allow household cylinders to overheat, and the presence of ventilation holes prevents the creation of an explosive concentration of propane-butane mixture even in the presence of gas leakage through the connecting fittings.

Very often people, especially summer residents, neglect safety and store gas cylinders indoors, next to gas stoves. This leads to overheating of gas cylinders and, as a result, rupture of their walls and explosions. Also, if there is a leak in the hoses or fittings, then the gas, being heavier than air, accumulates in places below the floor level and an explosive mixture is formed in the room, which, when gas burners are working, leads to unpleasant consequences, because gas has the same destructive power as TNT.

As a result of the rupture of the flask with gas, in the presence of an open flame or an accidental spark, fires occur. Due to fires that occurred as a result of spontaneous depressurization of containers with liquefied hydrocarbon fuel, not only the perpetrators of the incident suffer, but also neighbors and passers-by.

When the gas in the cylinder runs out, condensate remains behind, which must be drained at special stations. Some people drain it themselves, which also leads to dangerous consequences.

The presence of a large number of victims and significant destruction in a gas explosion is explained by the fact that fires are characterized by the occurrence of a volumetric flash (explosion), during which excess pressure is generated, leading to injury to people and destruction of building structures. The explosion causes the destruction of windows and the opening of doors, which contributes to the unhindered spread of the flame, and the flame front leads to the ignition of flammable objects, forming secondary fires.

Take care of yourself and your loved ones.

a) gas leakage through loose connections and the formation of an explosive mixture with air, which is dangerous in the presence of a spark, for example, when the cylinder hits a hard object;

b) thermal effect on the cylinder, which causes an increase in gas pressure in it. The cylinder must be filled with gas to ¾ of its volume; if the cylinder is filled with more gas, if it is brought into a warm room, the metal may rupture when warmed up;

c) mechanical shocks that can damage the walls of the vessel.

Propane is used as fuel for heating installations, for gas burners used in construction for roofing work, welding equipment, and household kitchen gas stoves. Also, propane can be used as a refrigerant in air conditioning systems and refrigeration units.

the pressure in the working chamber increased after the gas supply was stopped

safety valve is faulty

PRESSURE GAUGE:

there is no seal or stamp with an inspection mark

verification period has expired

When the pressure gauge is turned off, the needle does not return to zero by more than half the permissible error

glass is broken or there is other damage that may affect the accuracy of the readings

VALVE:

no fitting plug

presence of traces of oil, grease, dust

flywheel does not turn

there is a gas leak

It is forbidden to completely consume the gas from the cylinder! The residual pressure must be at least 0.05 MPa (0.5 kgf/cm2)

The residual pressure in acetylene cylinders must not be lower than the following values:

Scheme of the device and operation of the gearbox:

Inoperative position of the gearbox (gas does not flow) 1. Union nut for connecting the gearbox to the valve fitting 2. High pressure gauge 3. Return spring 4. Low pressure gauge (working) 5. Safety valve 6. Hose connection nipple 7. Membrane for rubberized fabric 8. Compression spring 9. Adjustment screw 10. Working (low pressure) chamber 11. Pressure reducing valve 12. High pressure chamber - Gas

The position of the gearbox parts when passing

The most dangerous damaging factor when using autonomous gas equipment is an explosion. Gas explosions, according to the reasons for their occurrence, can be divided into two types: fire and explosion after a gas leak due to poor quality gas supply from the source to the equipment or as a result of flame extinction, and explosion of the gas source itself, i.e. gas cylinder.

Gas leaks can be combated by installing a gas analyzer in the room, which will signal an alarm if the gas concentration in the room becomes explosive. With gas sources, i.e. Until recently, everything was more complicated with gas cylinders. Until a polymer gas cylinder appeared. Let's look in more detail at the advantages of polymer, or to be precise, polymer-composite gas cylinders, in comparison with metal ones.

A polymer gas cylinder, unlike a metal one, is not capable of being a source of explosion itself. Everyone knows that if a fire breaks out in a room where a metal gas cylinder is stored, then you should “admire” the fire at a respectful distance until an explosion occurs. But if instead of a metal one there is a polymer gas cylinder in the room, you can put out the fire without fear of an explosion. Polymer gas cylinders http://safegas.com.ua/ru/ do not explode in ordinary household fires. An explosion of such a gas container is still possible, but such high temperatures do not occur in domestic fires. The fact is that under the influence of temperature and an increase in pressure inside the cylinder, its body becomes membrane-like and allows excess pressure to pass out. This gas burns in a fire, the entire cylinder is engulfed in flames, it is useless to extinguish it, but there is no explosion, and therefore there are no potential casualties or destruction.

The second factor, which can also lead to an explosion of a gas container, is the so-called “pumping” of the cylinder. When refilling a cylinder in winter, you should remember that gas of the same volume at different temperatures creates different pressures inside the gas cylinder. If you fill a gas tank at the summer level in winter, you will pump in an additional volume of gas, which in a warm room will begin to increase the pressure inside the tank. And this pressure can increase so much that the metal cylinder simply cannot withstand it. A polymer cylinder can withstand pressure three times greater than a metal one, which absolutely eliminates depressurization and explosion as a result of this reason.

The cost of a gas cylinder http://safegas.com.ua/ru/ballonyi/ of the polymer-composite type is not much more expensive than a conventional metal one, so purchasing such a gas container will not hit your pocket hard, but will significantly reduce the risks associated with the operation of autonomous gas equipment .

Gas cylinders are not the safest products, but in some cases they are the only possible way to obtain heating, cook food, etc.

Although modern polymer composite cylinders are much safer than outdated metal ones, many people are still wary of them. It must be said that their fears are not unfounded. Gas cylinders do sometimes explode, although much less often than it might seem.

The explosion of a gas cylinder in a car or apartment is an emergency that can lead to very serious consequences, especially if there are other products near the exploded vessel. Such an emergency can lead not only to the destruction of property, but also to human casualties. Therefore, if you have to deal with gas cylinders, you should know why this happens.

The main reason for such incidents is violation of the rules for storing and operating cylinders. If the valve is not closed well enough, gas begins to escape and fill the room. Any accidental spark leads to an explosion and fire in the room.

Another option is to bring the cylinder in from the cold. If you bring a container from outside where it has been at a low temperature for a long time, a sudden change in temperature will cause the gas to expand and increase the risk of leakage.

Therefore, under no circumstances should you place a gas cylinder near a heat source. The build-up of pressure inside the balloon, which is created by the expanding gas, increases the risk of rupture of the vessel.

Microcracks or corrosion of the metal cylinder can form over time. Such damage may not be noticeable from the outside, but from the inside it creates a great danger.

This is another reason not to bring the cylinder from the cold into a very warm room - condensation forms on its surface, which also increases the risk of corrosion and a subsequent accident. If the cylinder is not made of metal, there is no such danger, but this does not mean that the gas cylinder can be handled carelessly.

Dependence of explosion on temperature

Winter is the most dangerous time of year for gas cylinders. As mentioned above, sudden temperature changes are one of the main enemies of such containers. The gas, which has the strongest destructive power, almost as good as TNT, can destroy an entire apartment, and the explosion can put people's lives in great danger. Not only the residents of the apartment, but also their neighbors and even just passersby, who at the time of the incident will be in close proximity to the explosion, can be exposed to danger.
If the cylinder was left in the cold, the gas in it is in a liquefied state. If you bring the cylinder into the heat immediately, the gas it contains will quickly turn into a gaseous state and expand greatly. The increased pressure can rupture the container, and since the gas ignites easily, it may not even require additional contact with the flame.

The problem with metal cylinders is that it is extremely difficult to control the gas level in them. An explosion is also caused by the fact that the ratio of gas in the cylinder does not meet the standards. An incorrectly filled cylinder, when exposed to a higher temperature, will certainly be ruptured by gas, which, when expanding, will simply have nowhere to go.

But the simplest and one of the most common causes of explosions is an insufficiently closed valve. The gas is heavier than air - when it comes out of the cylinder, it accumulates at the bottom near the floor, so at human height the leak may be detected too late. Even the smallest spark, static electricity or the contact of two solid objects can cause it to ignite.

How often do cylinders explode?

Every year in our country there are about three hundred accidents caused by the explosion of gas containers. According to statistics, such incidents occur much more often in the cold season due to refueling at low temperatures and subsequent transfer of the cylinder to a warm room.
The drop itself is not so dangerous. The cylinders can withstand a fairly wide range of temperatures - from minus 40 to plus 50 degrees Celsius. The temperature difference is only a “trigger” of an emergency situation.

Among the most common causes of explosions, statistics highlight the following:

• The cylinders did not undergo inspection (testing and pressure testing).
• Refueling at gas stations that evaluate the filling of a cylinder not by the pressure in it, but by the weight of the container being filled.
• Placing gas cylinders in residential premises or other premises in common use.

Consequences of a gas cylinder explosion

The consequences of an explosion in a house can include significant damage and destruction of property, as well as harm to human health and even death. The explosion also causes a fire, which increases its destructive power and makes such an incident even more dangerous for people.
During an explosion in an apartment, as a rule, windows and doors are knocked out, walls and partitions, including load-bearing structures, can be destroyed. Access to oxygen increases the area of ​​fire.

How to avoid an explosion

There are two ways to avoid such an incident as a gas cylinder explosion:

• Follow the safety regulations and operation of gas cylinders.
• Refuse metal containers in favor of modern composite-polymer products.

Composite polymer cylinders are not afraid of corrosion, and the walls of the container can become gas permeable as the temperature rises. In this case, the gas slowly leaves the cylinder and dissipates, without reaching such a concentration that a fire occurs. But the main thing is extreme caution when handling gas cylinders.