Gas cylinders are widely demanded both in industry and in medicine, aviation, space industries, in everyday life, as an autonomous energy source. They can be used both for heating and for lighting, cooking.

To eliminate all sorts of troubles associated with the operation, you need to choose the right type of equipment. Let's try together to understand the types of gas cylinders, the features of their design and connection.

Gas cylinders have been created for storage and transportation of compressed and liquefied gas - special vessels in which these substances are under high pressure. The first type of gas under any pressure is in a gaseous state, and the second, with an increase in this parameter, passes into the liquid phase.

Nitrogen, fluorine, oxygen, methane, hydrogen, as well as chlorine, carbon dioxide, ammonia are transported and stored in a compressed and liquefied state.

The container itself is an all-welded construction with at least 2 mm thick walls with a cylinder-shaped geometry. It is made of steel or polymer.

Its components:

• shell;
• neck;

The neck of the cylinder has a tapered thread for hermetically closing the outlet. In the event that, for some reason, gas expansion occurs, the valve will break off under the influence of pressure, and the pressure inside the vessel will return to normal.

The gas inside such a vessel is under a maximum pressure of 15 MPa. The cylinder body or shell has a single welded seam.

The volume of the balloon depends on the material from which it is made, the type of filling and purpose. Oxygen cylinders are both small-displacement - from 2 to 10 liters, and medium - 20 - 40 liters

In order for the gas inside the vessel to exert the same pressure on its walls, each cylinder has a convex bottom - upper and lower. For greater stability, the balloon is equipped with an annular support - a shoe. In addition, the gas tank is equipped with a metal or plastic cap that protects the valve during operation and transportation.

The cap is screwed onto the neck ring. Sometimes the balloon is provided with a pressure equalization function. The valve is a unit, which includes a steel body in the form of a tee, a flywheel, a shut-off element.

The assembly consisting of a check valve and a stem is called a plug. Each of the assembly parts performs its own function.

The valve is needed to regulate the gas flow through the body, and the stem is needed to engage the flywheel with the valve through torque. By turning the handwheel, you can close or open the gas flow.

All 3 valve parts are threaded. At the bottom, it is needed to attach the part to the cylinder, at the top, the valve stem is attached by means of a threaded connection. A plug is screwed onto the side thread

Types of gas cylinders

Gas vessels are classified according to many criteria: body material, volume, purpose, filler name, connection method. Both metal and composite materials are used for the manufacture of the case. Both have their pros and cons. You should familiarize yourself with them for the right choice.

Classification by body material

For the manufacture of the body of a metal cylinder, alloyed or low-carbon steel is used. The capacity of metal vessels is from 5 to 50 liters. Cylinders with a capacity of less than 50 liters are allowed to be installed inside the house, and 50 liters - only outside.

The latter need protection from direct sunlight. To do this, they are placed in a lockable metal cabinet with a marking on it corresponding to the type of gas. An empty metal cylinder weighs between 4 and 22 kg.

The vessel is filled with gas to a maximum of 85%. Depending on the volume, from 2 to 22 kg of gas is filled into the cylinder. This gas equipment is explosive and fire hazardous. Temperatures over 50⁰ are contraindicated for him. In case of sudden temperature changes and in the event of a fire, a powerful explosion occurs. It is impossible to turn over such a cylinder sharply, because this causes an increase in pressure.

Composite gas cylinder is a newer option. Its main advantage is complete explosion safety, even if a gas leak occurs. Liquefied gases are transported and stored in such containers. When exposed to an open flame, the gas leaves through the body gradually and simply burns out.

They are lightweight - 70% lighter than their metal counterparts, and have a stylish design. Thanks to the transparent body, you can always monitor the gas level. In contrast to metal, composite material does not corrode and therefore is more durable.

The polymer has excellent dielectric properties that are 100% non-sparking. The operating temperature range is within -40 - 50⁰. It is recommended to operate cylinders for up to 30 years. They must be re-certified every 10 years. Tank weight - 8 kg maximum.

Operation of a cylinder made of polymeric materials does not harm the environment, because no boron is added to the material

Composite gas cylinders are of two types: made by blowing technology and by winding fiberglass onto a mandrel. In the first case, the flask is made of polyethylene terephthalate. Next, manufacturers coat the vessel made of fiberglass strands with epoxy. The container is placed in a polymer body.

In the production of cylinders of the second type, a special mandrel is used. Fiberglass is wound on it, then the workpiece is impregnated with resins. First, two halves of the vessel are obtained. After curing, they are glued together and placed in a dense polyethylene casing.

Due to the presence of an overpressure valve and fusible rate, they have increased safety. In the event of a fire, the fusible link is triggered. Melting, it gradually releases gas, with full control over the process. After the insert is triggered, the cylinder is not subject to further operation.

Separation by installation site and purpose

All existing gas cylinders, depending on where they are installed and what they are intended for, are divided into the following types:

1. Household... They are used for heating, stoves, boilers.
2. Automotive... They are used on cars whose engine runs on gaseous fuel.
3. Tourist... Suitable for mobile devices such as blowtorches, burners, barbecue grills, heaters.
4. Industrial... This category includes containers in which gases are stored. Such cylinders are used in metallurgy, the chemical industry, and at pharmaceutical enterprises.
5. Medical... They are filled with breathing gas and transported in ambulances, used in hospital wards for intensive care and where oxygen cocktails are prepared. Such cylinders are used by rescuers and firefighters.

There are also universal cylinders that are used in many industries. For mobile gas appliances, disposable cartridges are produced that hold 100 - 450 g of gas. Visually, they resemble aerosol sprays.

Features of classification by filler

Based on the composition of the mixture, the cylinders are called propane, butane, hydrogen, nitrogen, acetylene, carbon dioxide, argon, oxygen, helium, etc. Each of the compositions has its own temperature regime.

For standard conditions, the difference between them is small. When a cylinder is required for use in high mountain areas or in very low temperatures, this parameter plays a decisive role.

Butane isomer is a mixture of isobutane with propane, well suited for low temperatures. It is safe for the ozone layer. Both propane and butane are very dangerous for humans. If they are inhaled, serious consequences for the body are inevitable. Direct contact with liquid butane causes the body to cool down to -20⁰.

Butane is used in lighters and is sometimes used as a refrigerant in air conditioners and refrigerators. Propane is essential in the manufacture of solvents. Acetylene is required to work with metal associated with welding and cutting. It is also used in the production of explosives, acetic acid, rubber, all kinds of plastics, for rocket engines.

Nitrogen is used by the electronic industry, chemical, oil and gas, pharmaceuticals, metallurgy. Hydrogen is necessary for the food industry, chemical. It is also used as a fuel for rockets and for welding.

Bicycle wheels, fire extinguishers are pumped with carbon monoxide or carbon dioxide. In the food industry, carbonated drinks are produced using it. In the form of dry ice, carbon monoxide is used as a refrigerant.

Cylinders with carbon dioxide are found in catering establishments, where drinks are cooled to a predetermined temperature, soda is made and sold on tap

In the metallurgical, metalworking industries, in processes where the interaction of the molten stream with oxygen is unacceptable, argon is used. It is also used in medicine for anesthesia, with its help they purify the air. Helium cylinders are necessary not only for filling balloons, but also for cutting, welding, melting metal.

This gas is part of breathing gas used in diving and can be used as a refrigerant in scientific experiments. Ammonia is a strong solvent. Since it is very poisonous, cylinders with it must be transported and stored very carefully. The same goes for chlorine containers.

Oxygen containers can be found near welding machines, where explosives, acids are produced, and oxygen cocktails are prepared. Compressed air transported in cylinders is most often used in the operation of pneumatic devices.

Liquefied natural gas methane is used as a sleeping pill in medicine, for the production of fertilizers, in the form of fuel. This gas is safe for humans.

Types of cylinders by connection method

Different models of gas cylinders are connected to the devices using four connection standards. The most popular is threaded a standard that meets all safety requirements. Products have 7/16 "thread. A hose or burner is attached to such cylinders by twisting.

The next cylinder standard is collet... This type of connection is also called push or clamp. A cylinder with this type of connection is considered the cheapest. Here, a cylindrical part plays the role of a clamp when connected. The collet can connect to threaded equipment, but requires an adapter.

The pierced type of cylinders is the most widespread throughout the world. These disposable cylinders have the disadvantage that the container cannot be disconnected until all the gas has been consumed. The latest models of SGS pierceable cylinders do not have this drawback.

Here it is possible to block the gas leak when disconnecting from the burner and turn off an incompletely emptied container. They are used for soldering, lighting lamps, portable stoves.

Most often, gas burners are designed for threads, but if a collet cylinder is available, you can use it by purchasing an inexpensive adapter

The valve connection is the type that is used mainly in Europe. The connection is simple and reliable with a high degree of leakage protection.

Decoding of marking of cylinders

By reading the label correctly, you can get complete information about the gas cylinder. If it is a propane cylinder, then its passport is in the area of \u200b\u200bthe valve, on a metal circle.

The passport of a propane cylinder indicates: working pressure in MPa, test pressure in the same units, actual volume of the container in liters, serial number, date of manufacture in the form "MM.YY.AA", where the first characters indicate the month, the second - the year , third - the year of the forthcoming certification.

This is followed by the weight of the empty cylinder in kg, the mass of the filled cylinder. The last line is the letter designation "R-AA". "R" is the stamp of the recertification site or the plant. The combination of characters "AA" reveals information about the year until which this certification will be valid.

The decision on the suitability of the cylinder should be made only after a complete decryption of all data about it. If defects are found on it, then it is emptied and sent for repair.

Oxygen cylinder marking has its own order and consists of four lines. The first contains information about the manufacturer, as well as the container number. The second contains the release date and the recommended inspection date. In the third - hydraulic and working pressure. In the fourth, the volume of gas and the mass of the cylinder without valve and cap.

When buying a cylinder, you should pay attention to how the information is applied to it. On the case, it is not applied with paint, but knocked out, and then coated with a special colorless varnish in order to protect it from corrosion. Often the last line contains the manufacturer's stamp.

Features of painting gas cylinders

Compressed gas cylinders in Russia and abroad are colored differently. At the same time, each type of gas corresponds not only to a certain color of the body, but also to the color of the strip, the inscription.

The table shows the identification colors of cylinders with some types of gases, as well as the color of the inscriptions and stripes.

Nitrous oxide is pumped into a gray cylinder with a black lettering and the same stripe. A protective-colored phosgene cylinder has a yellow inscription and a yellow stripe, and a cylinder of the same color, but with a black inscription and a green stripe, contains chlorine. The aluminum color of the cylinder, the black inscription on it and two yellow stripes indicate that it is filled with Freon-22.

For sulphurous anhydride, a black cylinder with a white stripe and a yellow inscription is intended. Ethylene is enclosed in a purple balloon with red lettering and a green stripe. For the rest of the combustible gases, red vessels with a white inscription and a green stripe are intended. Non-flammable gases are indicated by a yellow inscription on a black background of the case and a green stripe.

Types of cylinder malfunctions and their elimination

All malfunctions existing in gas cylinders are divided into two types: to be eliminated and not to be eliminated.

The first type includes:

• incorrect operation of the cylinder valve and pressure gauge;
• damage to the shoe or its displacement;
• damage to the threaded connection;
• leak of gas;
• peeling paint on the hull in many places.

The second type of malfunction is a significantly damaged surface of the case in the form of dents, cracks, swelling, and lack of markings. In this case, the cylinder is discarded. The decision on the possibility or impossibility of repair is made by a specialist with the appropriate qualifications.

When repairing gas cylinders, a simple replacement of defective elements is often performed. Sometimes an internal flushing of the vessel and a check for internal corrosion is required. Periodic inspection includes all these works, and upon completion a certificate is issued.

The gas cylinder in the photo is subject to repair. It needs to be painted and the valve replaced. The first work can be done independently, and the second should be entrusted to a specialist

This should not be done at home. All you can do yourself is paint the cylinder body. This must be done very carefully so as not to paint over the inscriptions or damage the markings. All other faults can only be rectified by a specialized workshop or the manufacturer.

Popular manufacturers of gas cylinders

Among the many manufacturers of cylinders, the Russian brand should be distinguished "Sledopyt"... It offers two types of gas cylinders with threaded and collet connections - for all-season mixture and winter. American firm Jetboil supplies to the market cartridges filled with propane and isobutane, which can be used in winter.

Mobile gas cylinders are produced by the South Korean trade mark Tramp. They are filled with all-season gas. Connection - threaded and collet

French company Campingaz produces all kinds of devices equipped with gas cylinders. Their connection type is collet, valve or puncture. Primus - manufactures gas cartridges of several types. All connections are threaded.

Good quality composite vessels are supplied by a Czech brand Research... The package includes special valves that protect the container from overfilling. All these cylinders are explosion-proof.

Conclusions and useful video on the topic

Video on the correct use and certification of gas cylinders. Tips from a specialist:

About composite LPG cylinders:

A gas cylinder is a useful thing in the household. So that its operation does not lead to undesirable consequences, you need to properly study the issue. And most importantly, adhere to basic safety rules.

After choosing the type of fuel it is necessary to determine the boiler output. You need to select a boiler based on the heat losses of the house. For example, to heat 10 m 2 of area with 3 m ceilings and good thermal insulation, 1 kW of power is required. But this is a very rough approximation. The fact is that not only the area of \u200b\u200bthe room determines the heat loss.

To be sure of the correct choice of the boiler, it is best to order from the design organization a calculation of heat losses or a project of the entire heating and water supply system.

The next step is the choice of a constructive type of heating boiler... Fortunately, many modern models of different designs allow them to be used in several power modes - this greatly simplifies the situation.

For a boiler with an open combustion chamber you need a room equipped with a chimney. If there is no chimney, you can install a boiler with a closed combustion chamber.

Compact size of wall and floor-standing boilers from renowned manufacturers will suit any interior - be it a kitchen, bathroom, attic, basement or a convenient niche. A floor-standing gas boiler is a time-tested device for heating and hot water supply of a country house.

Wall mounted gas boilers sometimes called mini-boiler rooms. Indeed, the burner, the heat exchanger, the control device, and many other components are located in one small housing. The main advantage of wall-mounted boilers is their compactness and ease of installation.

By the way of heating water boilers are subdivided into single and double-circuit.

Serves only for heating. Inside it there are no hydraulic elements of the DHW system, so it is cheaper than a double-circuit one. To supply the house with hot water, a water heat exchanger of a storage water heater is connected to a single-circuit boiler. That is, next to such a boiler, there will be a container of 50-1000 liters, which is specially designed for the preparation and storage of hot water.

An important addition to such heating systems - storage water heaters. They are also usually called water-to-water boilers or indirect heating boilers. First, because their design does not provide for an energy source that heats the water. Secondly, a tubular spiral-coil is inserted into the tank of such a boiler, into which hot water is supplied from the boiler, and the water in the boiler is already heated from the walls of this spiral.

To use hot water in normal city mode, a family of four usually needs a boiler with a volume of 250-300 liters.

Designed for both heating and hot water supply. In such devices, the elements of the DHW system are incorporated into the design. They are built in either instantaneous water heaters or capacitive ones.

The advantage of a double-circuit boiler over a single-circuit - full "combat readiness". The disadvantages include a limitation on the power of hot water supply and on the capacity of boilers. For wall-mounted built-in boilers, the capacity does not exceed 50 liters, for floor-mounted boilers - 160 L. Prices for gas boilers fluctuate depending on capacity - from 20,000 to 240,000 rubles. And the cost of a boiler is often comparable to the price of a single-circuit boiler.

Modern gas boilers achieve an efficiency of 93%... During the combustion of natural gas, steam is formed, which has thermal energy, which is lost together with the gases escaping through the chimney. On the other hand, gas condensing equipment allows the use of this thermal energy by cooling the steam in the boiler. That is, more heat is obtained during the combustion process - thanks to the additionally acquired condensate energy. Therefore, condensing boilers achieve an efficiency of 109% and also help to reduce gas consumption by 30% and reduce harmful emissions.

For this reason, the use of condensing units is legally encouraged in Europe. And in the UK, only condensing boilers have recently been allowed in residential buildings.

These boilers may have very decent power - 125 kW. This means that one such unit, with its small dimensions, is able to heat a rather large house. With a special chimney, cascade installations of several condensing boilers can be created. Moreover, all boilers are placed compactly on the wall and do not require a special room.

Estimated cost a wall-mounted condensing boiler can be determined by multiplying the value of its rated power by 3,000 rubles. And it is these boilers that experts recommend using as the most economical, environmentally friendly, compact and convenient.

Heat exchangers of modern floor-standing gas boilers They are made of gray cast iron, which, unlike conventional cast iron, is not subject to cracking due to internal stresses. Other models use high quality stainless steel.

There are various types of gas boilers.

Gas boilers are considered the most optimal.

They provide efficient space heating in the absence of access to the centralized heating system. The high demand for this type of heating equipment is justified by the type of fuel consumed. Natural gas is the most affordable resource today that allows you to obtain thermal energy. Due to the availability of a wide range, it is possible to select the optimal option for heating the room.

Classification of gas boilers

1. By the way of execution. There are floor-standing and wall-mounted types of boilers. A distinctive feature of floor-standing gas boilers is a wide power regulation range. They can be used to heat rooms up to 200 m². When working together with a broiler, this boiler provides maximum hot water supply. The difference between wall-hung boilers is their compact dimensions, which save installation space. Wall-mounted boilers are equipped with devices that ensure safe operation (interlock thermostats, flame sensors, traction control sensors, shutdown mechanism during power outages, etc.).
2. By the number of heating circuits. Single-circuit boilers are designed to heat the coolant or the heating system or hot water supply. Double-circuit are used in the simultaneous heating of the room and the supply of warm water. To solve individual needs, the purchase of a gas boiler with a boiler is suitable, which will allow you to have a constant supply of water (40-70 liters), or flow-through equipment.
3. By the method of discharge of combustion products. With natural draft in heating boilers, combustion products are removed by a constant flow of air from the street. Such devices are installed in non-residential premises or in small houses. If the device is equipped with a forced draft with a closed combustion chamber, then the air is taken in using a special chimney, consisting of an outer and an inner pipe. These boilers do not burn oxygen in the room and do not require an additional supply of cold air to keep the gas burning.
4. For energy efficiency. There are convection boilers that use a lower heating value. Such a heating system should be designed with the creation of all conditions that prevent condensation of water vapor, which contains dissolved acids, on the walls of the heat exchanger, furnace and chimney. Condensing boilers use a higher heating value. The room is heated by water vapor that forms on the walls of the economizer.
5. By type of ignition. With electronic ignition, it starts automatically. Such models are more economical due to the lack of an igniter with a constantly burning flame. In the event of a temporary interruption in the electricity supply, the boiler turns on automatically when the power is restored. In case of piezo ignition, the boiler will have to be turned on manually.

Wall mounted gas boilers

Like any others, wall-mounted gas boilers are the backbone of the entire heating system. They are considered the most affordable and common equipment for heating. Such a boiler carries the manufacturability and comfort when used in a country house.

Heating installation is carried out where the gas pipeline is located. They can be operated from a natural gas pipeline, as well as from a LPG cylinder. LPG cylinders are expensive and less efficient to operate than natural gas. To install a wall-mounted boiler, you must have a list of certain documents. Installation and maintenance of this type of equipment should be carried out by professionals who specialize in this equipment.

The presence of gas burners, gas fittings and a heat exchanger is the main unit of a gas wall-mounted boiler. Copper heat exchangers have the lowest cost and lightest weight. Such heat exchangers are used most often, but there are also steel and cast iron. Wall-hung boilers are equipped with controls, protection and self-diagnostics.

There are single-circuit and double-circuit wall-mounted boilers. Single-circuit are designed for space heating, and in order to heat water, a column or an electric broiler is installed. Double-circuit boilers can be used for both heating and hot water supply (not simultaneously).

With proper installation and operation, such a boiler can last up to 15-20 years (with a 1 year warranty). At the end of the warranty period, service must be performed. Maintenance is recommended annually.

Gas condensing boilers

Gas condensing boilers are reliable, modern and high-tech appliances.

Unlike conventional boilers, which pass combustion products through the heat exchanger grate, condensing boilers create a transfer of their thermal energy to the heat exchanger. Exhaust gases are discharged through the chimneys into the atmosphere, losing some of the heat. Together with the gases, fuel vapor is released, which is formed during combustion, reducing efficiency and taking part of the energy. This energy is stored by the condensing boiler and transferred to the heating system.

When cooled, the vapor is converted to liquid (condensation), which leads to the release of a certain amount of heat. A special heat exchanger collects condensation and transfers heat to the heating system. During the complete combustion of a unit of fuel, heat is generated, released by condensation. This phenomenon is called the higher heating value of the fuel.

Condensing boilers are highly economical. Due to the use of high-tech burners, the preparation of the fuel-air mixture in the required proportions for a given combustion mode is ensured.

This type of boilers can be both wall-mounted and floor-standing.

For condensing boilers, a heating system is installed with the expectation of a lower heating medium temperature. This project takes into account the return temperature of the heating medium. The temperature cannot exceed 60 ° C in any climatic conditions.

This type of heating devices is the most widespread in Europe. In many countries, it is forbidden to install any gas boilers, except for condensing boilers, since these boilers have the lowest emissions of harmful substances and the highest efficiency.

Types of gas burners in heating boilers

Classification of gas burners:

• by gas pressure;
• by design, which affects the ability of the gas to burn, as well as its mixing with air during combustion.

Burners are distinguished by the pressure of the gas supplied for combustion:

• low pressure. Up to 0.05 kgf / cm² (5 kn / m², 500 mm water column);
• medium pressure. From 0.05 to 3 kgf / cm² (5-300 kn / m², 0.5-30 m water column);
• high pressure. From 3 kgf / cm² (300 kn / m², 30 m water column).

By design and method of combustion, gas is divided into:

• diffuse;
• injection;
• gas turbine;
• two-wire;
• combined.

The principle of operation of diffusion burners is based on combustion, which occurs when combustible gas and air are mixed inside the combustion chamber. For this, at a certain pressure, gas is supplied to the burner, and air enters in a natural way. After mixing, a combustible mixture is formed.

The operation of injection burners occurs when gas and air are mixed inside the housing. Combustion air is injected, mixing with the gas through a special flare and nozzle to release the gas at high speed. They have full and partial mixing of the amount of supplied air.

In two-wire type gas burners, air is supplied by a blower fan. In the combustion zone, the combustible gas is mixed with air. They have the ability to work at low and medium pressure. This type of burner is compact and quiet in operation. Has a wide range of heat output with regulation.

The design of gas turbine burners assumes air supply using an axial fan, which starts to work when the turbine is turned on, which is located in the flow of the exhaust gas. The air is supplied in the opposite direction from the gas flow from the burner. In the next article - how much gas wall-mounted gas boilers burn.

Methods for stabilizing the flame of the burner in the furnace

The limits of the stable operation of the burners are the separation of the flame from the burners and the breakthrough of the flame into the burner.

The flame is stabilized using special devices and creating conditions to prevent break-off or breakthrough:

· Maintaining the DHW output speed within safe limits;

· Maintaining the temperature in the combustion zone not lower than the hot water ignition temperature.

When clean gas without air enters the burner, the flame is most stable in this case, because there can be no overshoot, and separation is unlikely, since such devices operate at low gas pressure.

In burners that have a ready-made gas-air mixture, i.e. gas and air, separation and slip are possible. Flame overflow into the burner can be prevented if:

· Reduce the outlet for DHW;

· Install a slotted stabilizer at the mouth of the burner with a slot size of no more than 1.2 mm or a mesh with a fine mesh, no more than 2.5 mm;

· If you cool the outlet of the burner.

The separation of the flame from the burner can be prevented by installing a constantly burning pilot burner at the mouth of the burner, using refractory tunnels of various designs, installing a dissecting stabilizer, installing a refractory hill made of refractory bricks in the boiler furnace. A slide (refractory) in the firebox prevents flame separation and maintains the temperature in the boiler firebox.

Gas-burners

A gas burner is a device that ensures stable combustion of gaseous fuel and regulates the combustion process.

The main functions of the burners:

· Gas and air supply to the combustion front;

· Mixture formation;

· Flame front stabilization;

· Ensuring the required intensity of the gas combustion process.

1. Diffusion burners.

2. Injection medium and low pressure.

3. Kinetic - with forced air supply of low and medium pressure.

4. Combined low and medium pressure oil-gas burners.

All burners must pass state tests in special testing centers and have a "Certificate of Conformity to Russian Standards"

(Tests:shakhty, Rostov region, Sverdlovsk region: "Ural test center of burners".

Diffusion burner... Diffusion is the process of spontaneous penetration of one substance into another.

In diffusion burners, all the air necessary for gas combustion is secondary. Diffusion burners are practically not used anywhere. A diffusion burner is a pipe with holes for gas outlet, the distance between the holes is determined taking into account the propagation of the flame from one hole to another. Such a burner is supplied with clean gas without admixture of air. The burners are low-power, require a large volume of combustion space or air supply to the furnace by a fan.

In industry at old factories, a bottom-slot diffusion burner is used, which is a pipe Æ 57mm with holes drilled on it in 2 rows.

The advantages of diffusion burners include simplicity of design and stable flame.

Injection burner.Air suction due to the vacuum created by the outflowing gas jet is called injection, or air suction is carried out due to the energy of the gas jet. Injection burners are available with incomplete (50 ... 60%) air injection and full injection.

In injection burners, primary air (50 ... 60%) and secondary air from the volume of the furnace participate in combustion. These burners are also called self-regulating (i.e., the greater the gas supply, the more air is sucked in).

The disadvantages of these burners: they need to stabilize the flame from separation and breakthrough. Combustion - noisy during operation.

The advantages of burners: simplicity of design, reliability in operation, the possibility of complete combustion of gas, the ability to operate at low and medium pressures, air supply due to the energy of a gas stream, which saves electrical energy (fan).

The main parts of the injection burners are:

· Primary air regulator (1);

· Nozzle (2);

· Mixer (3).

The primary air regulator is a rotating disc, washer or flap that regulates the primary air supply.

The nozzle serves to convert the potential energy of the gas pressure into kinetic (high-speed) energy, i.e. to give the gas jet a speed that would provide the required air flow.

The burner mixer consists of 3 parts:

· Injector (4);

· Confuser (5);

· Diffuser (7).

A vacuum is created in the injector and primary air is sucked in.

The narrowest part of the burner is the confuser, in which the gas-air mixture is equalized.

In the diffuser, the final mixing of the gas-air mixture and an increase in its pressure occur due to a decrease in speed.

Forced air burner. This is a kinetic or two-wire burner. Air for gas combustion is forced into the burner by a fan 100%, i.e. all air is primary. The burner is efficient, high power, does not require a large combustion space. It operates at low and medium gas pressure, needs to stabilize the flame from separation and breakthrough.

The burner has an air swirler designed for complete mixing of gas with air inside the burner.

The burner has a ceramic tunnel that acts as a stabilizer.

Combined gas-oil burners.In addition to the gas part, these burners have a nozzle for atomizing liquid fuel. Simultaneous combustion of gas and liquid fuel is allowed for a short time when switching from one type of fuel to another.

The nozzle is a tube-in-tube structure. Liquid fuel is supplied through the central pipe, atomizing air or steam is supplied through the annular space.

Electromagnetic fittings.

These are the KG-70,40,20,10 valves and the SVMG valve designed for automatic switching off and on of burners.

They work in an automatic blocking and regulation system designed to turn off the gas supply to the boiler in the event of a deviation of any boiler operating parameter from the normally set one.

Solenoid valves KPEG-100p, KPEG-50p are also designed to operate in an automatic blocking system for disconnecting voltage. Enabled only manually.

Valve device.

KG valves operate on gas pipelines with a pressure of no more than 0.5 kg / cm. The valve consists of a body, a cover, between which a diaphragm is clamped.

There is a metal disc at the top of the diaphragm, and a gasket at the bottom that acts as a valve. The gasket and the metal disc are bolted together.

In the upper part of the cover there is a cap, under which there is a bolt to limit the diaphragm deflection.

The KG valve includes a servo valve and an electromagnet coil. The servovalve has two holes, in the upper part there is a bypass, and on the bottom there is a relief one, which in turn are open and closed by a spool connected through the rod to the core of the electromagnet coil.

In the servovalve above the spool there is a short stiff spring, which, when the voltage is disconnected, is pressed tightly against the seat of the spool relief hole.

In the absence of voltage on the coil of the electromagnet, the spool of the servo valve under the influence of the weight of the core of the electromagnet, the force of the spring closes the relief hole, i.e. sits on the seat of the outlet.

The discharge of gas from the ECG supra-membrane cavity into the atmosphere is stopped through the vent hole, closed by a spool. The bypass in the servo valve remains open. The submembrane cavity of the valve communicates with the supramembrane cavity through the slots in the body, through the open bypass opening, according to the principle of communicating vessels. The gas pressure in the submembrane and in the supramembrane becomes equal. In this case, the membrane, under the influence of the weight of the disc on it and the force of the spring, blocks the gas passage.

When voltage is applied to the coil of the electromagnet, the core is pulled into the coil, through the stem it lifts the spool from the seat of the relief hole, opening it and closing the bypass hole in the upper part of the servo valve.

Gas from the supra-membrane cavity of the KG valve is discharged into the atmosphere through an open discharge hole through an impulse pipe. In this case, the pressure in the supramembrane cavity becomes equal to atmospheric pressure.

The membrane, under the action of the inlet gas pressure under it, will bend upwards together with the sealing gasket from the bottom, and will ensure the passage of gas to the burner. And the bypass opening of the servo valve is closed by a spool and aboutthe diaphragm and supramembrane spaces of the valve are not.

KG valve malfunctions:

1. Leakage of the valve to the seat. Gas passage to the burner in the furnace.

2. Leakage of seating of the servo valve spool to the seat of the relief hole. In this case, if the waste pipe is cut into the burner outlet gas pipeline, according to the passport for the manufacturer's valve, the furnace will also be gassed.

3. Leaky shut-off by the spool of the bypass opening of the servo valve (voltage is applied to the coil, the valve is open). With such a leak, the valve may close due to the fact that the gas from aboutof the diaphragm cavity through the slots in the body and the leaky closed bypass hole will enter the above-membrane cavity of the valve and it will close. To eliminate the leaks (above), it is necessary to replace the sealing surfaces, while showing extraordinary imagination, because Spare parts are not supplied by Russian enterprises. To eliminate leaks in the servovalve, it is possible to regulate the spool stroke with a device located in the connection of the electromagnet core with the servo valve spool stem.

4. Gas leaking to the outside through the servo valve gasket (blue).

5. Gas leaking through the bolt in the valve cover under the bonnet.

6. Leaking assembly in the center of the valve diaphragm. If the leak is strong, the pressure above the diaphragm and below the diaphragm will equalize, the valve will close and shut off the gas.

7. Membrane rupture. With the valve open, when voltage is applied. The pressure above and below the diaphragm will equalize and the valve will close. Diaphragms usually break around the perimeter where the diaphragm is bolted down.

8. A plastic sleeve flexes at the top of the servo valve. The tightness of the closing of the bypass opening is broken.

9. Gas leaks through micropores in the housing, cover.

10. The coil of the electromagnet has burnt out.

The following types of gas appliances are distinguished according to the method of removing combustion products and supplying fresh air: type A:these devices must not be connected to a chimney or to an outdoor exhaust. Example:gas stove in the kitchen.

Apparatus type B:these devices must be connected to a chimney for the removal of combustion products. Fresh air for the burner comes directly from the room where the device is installed.

Example:Wall mounted boiler.

Apparatus type B1:it is a type B apparatus equipped with a draft breaker / anti-blower in the burner circuit.

Note:This apparatus will be an apparatus type B2,if it does not have a fan.

Apparatus type B2:this is an apparatus type B,not equipped with a draft breaker / anti-blower.

Note:The apparatus is called apparatus type C,if it has a closed combustion chamber (room air is not used).

16.6.2.2. Separate chimney for gas appliances
tov type B

This is a chimney that serves only one room. A gas boiler can be connected to such a chimney. The combustion products are removed by natural draft. Such a chimney can be used as an outlet for removing polluted air from the room, provided that the upper part of the inlet of the draft breaker is located at a height of at least 1.80 m from the floor (see Fig. 16.42). The chimney section is determined from table. 1 b. 2 depending on:

From the height of the chimney (example: the height of the chimney is from 4 to 10 m);

The presence or absence of a change in the direction of the chimney
(fig. 16.33-16.35) (example: straight chimney or with elbow);

From the diameter of the connecting pipe (outlet of the device) and possible elbows (see types I - IV in Fig. 16.36) (example: type II, if the connection is type I with a 90 ° elbow);

From the power of the boiler (example: a boiler with a power of 23 or 28 kW or
more).

Example:

Thermally insulated straight flue:

(r≥ 0.22 m 2 ° C / W)

Connecting the boiler with a 90 ° elbow to a type II chimney,

Chimney connection diameter: 125 mm,

Chimney height: from 4 to 10m,

Muna B1 boiler: maximum net power 4 kW.

We find from the table:

Horizontal: mun // → Ø \u003d 125 mm -\u003e power 41 kW.

Vertical: ascending at a right angle from 41 kW to 4 ≤H< 10м.

We get: chimney section 200 x 200 mm.

Note: Flue ducts of rectangular cross-section must satisfy the condition: length / width ≤ 1.6.

Important! A boiler connected to a natural draft chimney must not be installed in a mechanically ventilated room, as the room can create vacuum and back draft conditions.

Materials used for chimneys:

Cylindrical ceramic tube with solid or porous walls;

Cylindrical pipe made of concrete with an admixture of pozzolan (with a technical expert opinion);

Double wall metal pipe;

Casing pipe (shell) (rigid or flexible):

Titanium stabilized 18/8 stainless steel

Made of A5 aluminum (99.5% purity) 0.8 mm thick.

□Pipe upsetting

Upsetting is called an operation, which consists in the fact that a separate pipe is inserted into the chimney to remove the combustion products (Fig. 16.37 - 16.39).

Double-walled chimney with asbestos insulation. Double walls made of stainless steel increase the anti-corrosion properties of the chimney. This method is used when necessary:

Coordinate the cross-section of the chimney with regulatory requirements and with the type of heating installation;

Provide protection against corrosion or the formation of soot on its walls and rapid removal of combustion products.

□Installation: highlights

Ventilation at the bottom and top of the annular space,

T-piece with a cleaning hatch at the bottom of the chimney,

Protection of the chimney outlet from rain,

Casing size (see table 16.2).

□Chimney height above the roof

Recommended rates are shown in Fig. 16.40 for roof slopes\u003e 15 °. The pipe mouth should be located at such a height that adjacent obstacles cannot create conditions of increased pressure at its location.

Note: When the roof slopes< 15° жерло трубы должно располагаться как минимум на 1,20 м выше точки выхода трубы и как минимум на / m above the acroteria, if the latter is at a height\u003e 0.20 m.

Prescriptions

□Room volume

Gas appliances with an open combustion chamber must not be installed in a room with a volume of less than 8 m 3.

□Fresh air supply to the boiler furnace

Any apparatus with a combustion chamber requires fresh air to operate the burner. The supply of air and the removal of combustion products directly affect the hygienic state of the room in which the gas apparatus is located.

Each main room of the house has at least one fresh air inlet.

Modules of used air inlets are equal to 20 and 30 m 3 / h in the main rooms (living room and bedrooms).

When removing combustion products due to natural ventilation, it is only necessary to control the sum of M modules of air inlets, depending on the power of the installed devices. In this case, two cases are distinguished:

1. There is one gas appliance in the room that is not connected to the ventilation system (for example, a gas stove). In this case, M should be\u003e 90.

2. A gas boiler with a chimney and a gas stove without a chimney are installed in the room. In this case, M ≥ 6.2 Pu, where Pu is the sum of the useful capacities of the gas apparatus connected to the hood.

Example.In a T4 country house, a 28 kW gas boiler is installed in the kitchen, connected to a natural draft chimney. Air inlets with a module of 30 m 3 / h -\u003e total module M \u003d 90 m 3 / h are installed in 3 rooms. The canteen has 3 air inlets with a module of 30 m 3 / h -\u003e total module M \u003d 90 m 3 / h. The sum of all modules is equal to M \u003d 180 m 3 / h. The condition M ≥ 6.2 Pu is satisfied (6.2 x28 \u003d 173.6).

□Discharge of polluted air

Each service area has several natural draft or mechanical exhaust vents (fig. 16.41 and 16.42).

→With natural draft,if there are several
gas appliances not connected to the ventilation system (on
e.g. gas stove), at the top of a vertical duct
there must be an exhaust hole with a diameter of at least 100 cm 2.

→With an adjustable ventilation system(РСВ) outlet is polluted
air can be carried out:

Through the exhaust port of the regulated ventilation system (see Section 16.6.2.4);

Through the draft-breaker of the apparatus, if it is connected to a regulated gas ventilation system (PCV-gas), provided that the upper part of the inlet of the draft interrupter is located\u003e 1.80 m from the floor.

In all cases, if it is necessary to quickly remove polluted air, it is necessary to provide a window with a minimum area of \u200b\u200b0.40 mm 2 or a light yard with a width of at least 2 m.