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Why gas cylinders explode: main causes and preventive measures. Causes and consequences of a gas cylinder explosion Foreign impurities in the gas

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

Although modern polymer composite cylinders are much safer than obsolete metal ones, many people are still wary of them. I must say 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 is happening.

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

Another option is to skid the balloon from frost. If the container is brought in from outdoors 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, in no case should a gas cylinder be placed near a heat source. The pressurization 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 may develop over time. From the outside, such damage may not be noticeable, but from the inside they create a great danger.

This is another reason not to bring the cylinder out of 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.

Temperature dependence of the explosion

Winter is the most dangerous time of the 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, practically not inferior to TNT, can destroy the entire apartment, and the explosion can put people's lives in great danger. Not only the residents of the apartment can be exposed to danger, but also their neighbors and even just passers-by, who at the time of the incident will be in the immediate vicinity of the explosion.
If the cylinder was in the cold, the gas in it is in a liquefied state. If you immediately bring the balloon into heat, the gas contained in it will quickly turn into a gaseous state and expand greatly. The increased pressure can rupture the balloon, and since the gas is flammable, it may not even require additional bending contact.

The problem with metal cylinders is that it is extremely difficult to control the level of gas 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 if it hits more than high temperature will certainly be torn apart 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 leaves the cylinder, it accumulates near the floor, so at the level of human height, a leak can be detected too late. Even the smallest spark, static electricity, or the contact of two solid objects can ignite it.

How often do balloons 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 the subsequent transfer of the cylinder to a warm room.
The drop itself is not that dangerous. Cylinders 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.

Among the most common causes of an explosion, statistics highlight the following:

Cylinders did not pass inspection (testing and pressure testing).
Refueling at such gas filling stations, which evaluate the filling of the cylinder not by the pressure in it, but by the weight of the container being filled.
Placement of gas cylinders in residential premises or other premises that are in common use.

Consequences of a gas cylinder explosion

The consequences of an explosion in a house can be both significant destruction 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. The access of oxygen increases the fire area.

How to avoid an explosion

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

Observe the safety regulations and operation of gas cylinders.
Abandon metal containers in favor of modern composite-polymer products.

Composite-polymer cylinders are not afraid of corrosion, and the container walls can become gas-permeable when the temperature rises. In this case, the gas slowly leaves the cylinder and dissipates, not reaching such a concentration that a fire starts. But the main thing is the utmost caution when handling gas cylinders.

Agree, the news that somewhere there was an explosion of a gas cylinder, which, unfortunately, we sometimes hear on TV or from friends, makes us think about our own safety. And there is no place for complacency that this will not happen to us.

The consequences of such an explosion and the resulting fire can be the saddest, and not only for property, but also for the health and life of people who are nearby. We will help you understand why gas cylinders can explode, and how, without giving up the convenience of their use, to protect yourself from big troubles.

To do this, we conducted a study of the features of existing types of household gas vessels, analyzed the reasons for which explosions occurred in a number of real cases, and studied the competent opinions of experienced users about this. The proposed article can be presented as a compilation of sets of rules, set out in an understandable form, that allow in practice the correct and safe use of gas in cylinders.

The indispensability of gas cylinders in everyday life so far can be confirmed with certainty by a significant part of the population of Russia.

For many people, the use of liquefied gas cylinders is not just an opportunity to have additional amenities in the country, but the only affordable option gasification of your residential building

At the state level, Rostekhnadzor identified common problems in the use of gas vessels that you need to be aware of, as they are related to their safe use:

outdated fleet - about 90% of all cylinders are not protected from overfilling during refueling;
lack of clear state regulation in the field of circulation of cylinders on the market, which can include the presence of illegal gas stations;
the need to improve and bring the norms of technical parameters to international standards.

In addition to knowing the general problems, to make it easier to imagine the causes leading to an explosion and the conditions that can contribute to this, it will be useful to know what cylinders exist, understand the device, understand some of the nuances of the physics of the explosion and combustion of the mixture used in them.

Types of gas vessels

Depending on the field of application, the filler used and the connection methods, they may differ both structurally and in the material from which the case is made.

Heating or cooling of vessel walls

The propane-butane mixture, having a large coefficient of expansion, even with a slight increase in its temperature, greatly increases in volume.

The danger of increasing the pressure of the mixture on the walls of the flask also exists in a cylinder installed next to a heat source.

In addition to heating, a number of dangers are also fraught with the negative impact of negative temperatures. The first is an increase in the fragility of the metal. And secondly, it is necessary to remember forever that in no case should a vessel that has been in the cold for a long time be brought into warm room. A sharp increase in the temperature of the hydrocarbon mixture is unsafe.

Hits and drops of cylinders

Sharp mechanical impacts on its walls can provoke damage and ignition of a vessel with gas, especially when the tank is in conditions of low or, conversely, too high temperatures.

When using a cylinder in abnormally cold conditions, the mechanical properties metal - the impact strength of steel decreases.

For this reason, a strong blow to the cylinder or its hard fall can damage the tightness of the vessel and contribute to the release of gas, which, mixed with oxygen and in contact with a spark, will lead to detonation of the gas-air mixture.

In the second case, an increase in temperature and heating of the gas contained in the flask, as was said, sharply increases its pressure, which, with additional impacts on the vessel, can break it.

foreign matter in gas

The danger of an explosion lurks when water and hydrogen sulfide get into a vessel with liquid gas. Their high content in the tank contributes to the appearance of delaminations and bulges on the inner metal surface of the shell.

Such vessel defects occur when hydrogen sulfide is present in propane from 0.3% or more, and can be observed after a two-year period of use of the cylinder.

Weld defect

Less often, but there are problems associated with the depressurization of gas vessels in the near-weld zone.

In the event of a defect in a weld, a weakening of its working section can occur, stress concentration and, as a result, opening of a longitudinal or circumferential weld

The overall integrity of the shell may be preserved if a defective weld breaks.

Scenarios of the consequences of a cylinder explosion

The above reasons for the explosion or fire of gas vessels may various options provoke the following dangerous scenarios.

Cylinder rupture and flame ejection

The explosion of a cylinder and the ignition of propane-butane are dangerous due to the following factors:

a column of strong flame, rapidly increasing the area of the fire;
high temperature of the fire in the explosion;
toxicity of combustion products.

The defeat can also come from suffocation, due to a significant decrease in oxygen with a sharp concentration of harmful gases.

Conducted studies have shown that the sealing of a 50-liter gas vessel with liquefied gas caught in a fire breaks down in less than 5 minutes. As a result - a flash fire with the release of a "fireball" reaching a diameter of 10 m

Usually, the rupture of the vessel occurs along its lateral part.

Secondary damaging effects from the explosion

Secondary, but no less serious damaging effects in the explosion of a cylinder are:

valve separation;
the impact of a compression wave or shock wave;
damage from shell fragments.

Fragments from the cylinder and its detached elements can scatter very far, causing damage in a radius of up to 250 m, and rise to a height of thirty meters.

Danger of gas leakage

The danger of propane leakage from a damaged tank lies in the fact that an explosive concentration of a mixture of hydrocarbon and oxygen is created in the room very quickly and in large volumes - much faster than with leakage of liquid combustible substances.

A strong leakage of a mixture from a flask or a faulty stop valve can be determined by smell or by ear - the sound is similar to what we hear when we quickly blow off a balloon.

If a gas leak is suspected or in order to control its absence, it will be enough to apply a soapy solution to the cylinder with a sponge and determine the place of depressurization by the bubbles formed.

If there is a gas leak, then it is necessary to cover the place of depressurization with a wet rag, carefully take the vessel outside and call the gasmen.

Since 2016, the technical regulations have provided for the mandatory installation of gas alarms in new homes. For previously built housing, this norm is advisory in nature, but the benefits of this device, especially in houses where bottled gas is used, are undeniable.

The fact is that the density of the hydrocarbon mixture is greater than the density of air. If the sealing of the flask, shut-off equipment or connecting hose is broken, the gas begins to accumulate at the bottom, and its smell may not be immediately detected. That's why a propane mixture released into the air from a damaged gas cylinder often explodes in houses from any spark without being noticed.

Fundamentals of Safe Cylinder Handling

Before installing the balloon and

Only certified cylinders supplied by specialized organizations, having a paper passport for all operation cycles and the corresponding marking applied by impact branding, will be used.

To the main technical requirements that must be observed when operating cylinders include:

All cylinders, with the exception of one (five-liter for connection to gas stove) should be installed in outbuildings outside buildings and at a distance not closer than 5 m from their entrance.
Avoid storage of cylinders in living rooms, basements and attics.
Do not place cylinders closer than 1 m from heaters and 5 m from open flames.

Obvious, but often forgotten safety measures when using vessels with gas, the following should be attributed and taken for strict execution:

Do not bring a lit match or lighter near the cylinder to check for gas leaks.
Categorically exclude the use of open fire to heat the gearbox or valve. For these purposes, only hot water is allowed.
If gas is detected in the room, do not turn on any electrical appliances, including lights, and do not turn them off. The temperature of a spark in a socket or switch can reach up to a thousand degrees.
Do not attempt to repair valves and other structural elements of the cylinder yourself.

In addition, you must strictly follow the time frame prescribed by the manufacturer for the use of cylinders. Vessels manufactured before December 2014 can be used for 40 years.

In the absence of information on the permitted period of use of gas cylinders manufactured after this date and not having accompanying documentation for them, Rostekhnadzor recommends taking 20 years as the cylinder's shelf life.

It is strictly forbidden to carry gas cylinders using the valve as a holding device. This can cause depressurization or breakage of the locking device.

A safe alternative to steel gas cylinders are more modern polymer-composite vessels - eurocylinders. Their flasks are protected by a plastic casing, do not accumulate static electricity. The explosion safety of composite cylinders is ensured by equipping them with safety devices of a new generation - a fusible link and an overpressure relief check valve.

Conclusions and useful video on the topic

Causes of explosions of gas cylinders on examples of real facts, and what can and what absolutely cannot be done when using them:

How to properly use gas cylinders in everyday life, and what requirements they must meet:

With all the existing risk factors that accompany the operation of gas-balloon equipment, there is no reason to give in to fear and refuse the convenience of using them in everyday life.

Theoretical knowledge of the causes and conditions accompanying the explosion of household gas cylinders is designed to help in overcoming such fear. And compliance with the given set of norms safe use will serve as a reliable insurance against the severe consequences of a gas explosion and fire.

If you have valuable information that can complement our material, please share it with other site visitors - leave your comments in the block below. There you can also ask questions about the topic of the article.

Experts continue to find out the cause of the tragedy in the children's tent camp

Investigators continue to find out. The schoolchildren, who went on a camping trip, suffered from the explosion of a gas cylinder, which they took with them for cooking.

A consultant - a technologist of a specialized store told MK about the conditions under which depressurization and an explosion can occur in a gas cylinder. And also how hunters have fun buying them in whole boxes.

Photo provided by the press service of the Ministry of Emergency Situations

It is already known that a gas cylinder with a volume of 530 milliliters exploded during the hike. These are used by tourists and fishermen to cook food on gas burners.

- Are these small 230 and 530 gram gas cylinders produced in Korea?

They used to come from Korea. They were released there under the brand name "Pathfinder". As soon as the dollar and euro rose, one of the enterprises in Novosibirsk began to produce them under the same brand. I can't say exactly.

How could a spray can ignite, because there is a very high degree of protection there? The product is certified, there is GOST, the bottle itself, as they say, is sealed, like a "moon rover".

The temperature of its use is from -20 °С to +35 °С. Or he was in the open sun for a long time, and the maximum allowable pressure was exceeded. Or was the impact of open fire.

It was reported that the tragedy happened on the campaign. An autonomous group of children went from the camp along a certain route. An eyewitness said that they were sitting by the fire when they heard a loud bang. Some of the children's hair was severely scorched, and one girl was taken to the ambulance in her arms. With a 20-25% body burn, she is now in intensive care.

The guys could run, play, someone could accidentally push or move the balloon to the fire. It is not clear otherwise. Why did they need to kindle a fire if they took a gas cylinder with them for cooking? Probably, making a fire was part of the curriculum. Children are taught to make a fire with one or two matches. But I know one thing, right conditions gas cylinders do not spontaneously explode during operation. But our people love to have fun in nature. Many, after they use up the gas in the cylinder, throw it into the fire to get a big “bang”. Even an empty bottle explodes with a loud bang. Our hunters take these cylinders in whole boxes, they cost - then they are cheap. Then they have fun in the evening, lying "in ambush", throwing even full gas cylinders into the fire. Or shoot balloons from guns. Surprisingly, there have been no accidents so far.

A source in law enforcement agencies said that according to the preliminary version, the cause of the explosion could be the depressurization of the cylinder, which was refilled in a makeshift way. Is this possible or is it still one-time use?

They can reload, although this is strictly prohibited. They do this to save money. There are craftsmen who take the appropriate orders. To do this, they buy special adapters, and they are filled from a large gas cylinder. A small factory cylinder has a weight of 230 grams, those who fill the cylinders, as they say, for themselves, and know that they will not keep them under the scorching rays of the sun, are already pumping more gas into it - 250 - 260 grams. Accordingly, this is an additional load on the walls of a metal vessel. And even with a short exposure to sunlight, a rupture is possible. Therefore, those who refill cylinders at home put them on sensitive scales. It is very important not to download too much, you need a clear control.

- It's still necessary to choose the right composition of the gas.

He's already picked. Take a 50-liter bottle and pour it out. There are three base hydrocarbon gases mixed: 30% propane, 11% butane and 56% isobutane.