Reducer for household gas cylinder performs a function comparable to that of a stabilizer in the operation of an electrical system; this device is a device, but for gas equipment. Its main goal is to reduce the gas pressure coming from a gas pipe or from a gas cylinder to the required value of the equipment to which the blue fuel is supplied.
The next most important function of the gearbox is to automatically maintain the operating pressure at the proper level. Reducers for gas cylinders differ in shape, size, weight capacity, etc. But according to the principle of operation, these devices can be divided into only two types: direct and reverse gearboxes.
The principle of operation of a gas reducer for a cylinder
Direct type gearboxes are designed in such a way that the gas passing through the fitting opens the valve and presses it to the seat using a spring, and high-pressure gas stops entering the chamber. Next, the membrane pushes the valve away from the seat, the pressure gradually decreases, reaching the operating pressure level of the one to which the reducer is connected.
As a result, the spring straightens, the valve moves away from the seat and ceases to prevent the flow of new volumes of gas fuel. If the pressure begins to increase again, then this spring is again pressed down by the valve and gas does not enter the device.
In reverse-action gearboxes, when gas enters, the valve compresses and prevents it from entering the device. With the help of a special adjusting screw, the pressure spring begins to compress, the membrane bends, the transfer disk presses the return spring, the valve rises, and the gas again moves into the chamber of the device.
Gas reducer "frog" for a cylinder
In the working chamber, the gas pressure increases along with the pressure in the gas pipe or in the cylinder, the membrane is straightened with the help of a spring, the transfer disk moves down, presses on the return spring and, under its influence, the valve is again pressed against the seat. It should be noted that gearboxes of the second type of action, i.e. reverse gearboxes are more popular than direct-acting gearboxes, as they are considered safer.
Features of using gas reducers in everyday life
We know that gases are divided into flammable and non-flammable. At the same time, I would like to remind you that gearboxes for different types of gases do not differ in appearance from each other, and in order to distinguish them, it was customary in the manufacture of devices to make threads for gases with flammable properties - “left”, and for non-flammable gases - “right” .
Gearboxes operating on various types of gas are used in a variety of areas of industry, agriculture, construction, and medicine. For example, oxygen reducers are used in gas welding, cutting, and in the work of medical institutions, and acetylene reducers are used in body work at car service and repair stations.
Propane reducers are used in construction, especially in roofing work, but the main purpose of such reducers is the supply and regulation of gas from gas cylinders to.
More recently, outdated gas containers have been replaced by new, so-called composite cylinders, which differ from their predecessors in lighter weight and a higher level of safety. New technologies have advanced so much that even if, God forbid, of course, something happens to such a cylinder, then when it explodes you will not even find fragments.
Composite gas cylinders
Composite cylinders do not rust inside, but their use, of course, places higher-level demands on us. The regulator must ensure constant pressure at the outlet of the composite cylinder and keep it at the operating level. To work with new types of cylinders, regulators that meet European standards are used.
These gearboxes include the A300i-A310i gearbox, which differ from the gearboxes we are used to in the following characteristics:
— the presence of an easily tightened nut;
— increased gasket service life to 10 years;
- a type of construction that ensures more reliable tightness of connections.
Household reducers for gas cylinders most often have a very affordable price, and considering the role these devices play in ensuring the safety of not only our homes, but sometimes our lives, their cost can be called absolutely acceptable.
When choosing a reducer, it is necessary to take into account all the details: what gas the device will be intended for, what type of gas cylinder will be used, what diameter is needed, etc. For example, it is recommended to purchase a reducer from the same manufacturer as the device itself to which gas is supplied.
Types of gas reducers for gas cylinders and prices
Let's look at some types of regulators for gas cylinders, which are in good demand in the gas equipment market.
Household gas reducers RDSG for propane
The RDSG-1-1.2 “frog” device with thread and RDSG-2 “Baltika” without thread have a very simple design and, apparently for this reason, a fairly low price.
Differs in the following characteristics:
— inlet pressure — 0.07-1.5 MPa;
- outlet pressure - 2950-3300 mPa;
— weight 310 g;
— ability to withstand temperatures from -30 to +45 degrees Celsius;
— throughput 1.2 m3 of gas per hour.
The price of such a gearbox ranges from 150 to 200 rubles.
The M714 gearbox is made in Italy and costs only 50 rubles more, having:
— inlet pressure 20 bar;
— outlet pressure 30 m bar;
— has an elastic gasket with a long service life.
Gearbox N240:
— inlet pressure — 18 bar;
— ability to adjust pressure from 20 to 60 bar;
— the ability to operate the device at temperatures from -20 to +50 degrees.
The cost of the gearbox is about 1000 rubles.
Gearbox BPO-5 (miniature).
— inlet pressure 2.5 Pa;
- outlet pressure - 0.3 Pa;
— weight only 650 g.
Gearbox BKO-25:
— inlet pressure -20 mPa;
— working pressure - 0.8;
— weight 2 kg;
— throughput capacity 25 m3 of gas per hour.
Gas propane reducers BKO-50 and BPO-5
Gearbox BKO-50:
— inlet pressure 20;
— working pressure 1.25;
— weight 2.1 kg;
— throughput capacity 50 m3 of gas per hour.
Gearbox BVO-80:
— inlet pressure 20 MPa;
— working pressure 1.25;
— weight 2.1 kg;
— throughput capacity 80 m3 of gas per hour.
Reducer RKZ-250:
— inlet pressure — 20 MPa;
— working pressure — 1.6;
— weight 13 kg;
— throughput capacity 250 m3 of gas per hour.
Reducer RKZ-500:
— inlet pressure 20 MPa;
— working pressure 1.6;
— weight 13 kg;
— throughput capacity 500 m3 of gas per hour.
Don't forget that each type household reducer for gas cylinder designed not only for a specific purpose, but also for a specific gas. If the documents for the device indicate the word “propane”, then this reducer cannot operate on methane. Following these simple rules will ensure not only an uninterrupted supply of gas from the cylinder to the gas appliance, but will also preserve your health, and maybe even your life.
This regulator (stabilizer) is intended for use with household equipment; it provides precise control of the outlet pressure, regardless of the gas pressure entering it.
The regulator (stabilizer) is used in autonomous or stationary gas supply systems and ensures the supply of gas at the required pressure to household appliances, smoothing out possible fluctuations (increases) in pressure and ensuring stable operation of the appliances. This reducer is also installed in cases where devices with different input pressure requirements are connected to the same low-pressure pipeline.
Regulates pressure from low to low.
It has in its design:
- underpressure shut-off valve (UPSO)
- overflow shut-off valve
Models
Those. data
- Inlet pressure: up to 400 mbar
- Outlet pressure set: 20 mbar
- Input thread: G 3/4" internal (right).
- Outlet thread: G 3/4" internal (right).
- Operating temperature range: from -40С° to +60С°
- Capacity: up to 15 kg/h (6-10 m3)
- Weight: --- g.
- Service life: up to 10 years.
Add. information
Examples of the use of stabilizers.Example 1: The pressure in the pipeline is 50 mbar. A boiler with an operating pressure of 50 mbar and a stove with an operating pressure of 30 mbar are connected to it. A stabilizer is placed in front of the stove, which reduces the pressure from 50 mbar to 30 mbar.
Example 2: in a village with main gas, the gas pressure jumps. In the evening, at maximum flow, the pressure is normal. High blood pressure day and night. Installing a stabilizer solves the problem with increased pressure.
The main task of the gas reducer is to reduce the gas pressure coming from a gas pipeline or cylinder to a working value and maintain it in a given range in automatic mode. In this case, changes in the pressure of the gas mixture entering the gas cylinder reducer should not have any effect on the operation of the device. Despite the clarity and conciseness of the definition of the method of operation of a gas reducer, according to the principle of operation they can be divided into two completely different types.
When gas passes through the fitting and enters the high-pressure chamber, an action is observed that promotes the opening of the valve. The pressure-reducing valve is pressed directly against the seat thanks to a locking spring, which thereby eliminates the possibility of access of gas under high pressure.
The main task of the membrane is to remove the pressure-reducing valve from the seat, which helps reduce the gas pressure and its entry into the chamber with operating pressure. We can say that the membrane is exposed to two opposing forces:
- Pressure spring action required to open the valve
- Action of low pressure gas from the reducer chamber
When the gas pressure in the working chamber decreases, the pressure spring straightens, the valve leaves the seat and opens the way for a new portion of blue fuel. As the pressure increases, the spring, on the contrary, compresses, pressing the valve even more tightly to the seat, which limits the flow of gas into the reducer.
The adjusting screw makes it possible to adjust the operating pressure by changing the pressure on the spring. Obviously, when turning it out, the working pressure will decrease, and when wrapping it, it will increase.
A pressure gauge installed on the working chamber will allow you to control the pressure at any time. It should be noted that in practice, gearboxes for direct-type gas cylinders have not found very wide application.
Reverse type
When gas enters the working chamber from the cylinder, the valve contracts, which prevents the flow of fuel. The flow can be adjusted with a special screw, which, when turned out, compresses the pressure spring and bends the membrane. In this case, the transfer disk is pressed against the return spring, the valve is lifted and gas penetrates into the working chamber. How is the working pressure adjusted automatically?
Simultaneously with the increase in pressure in the gas pipeline, the pressure in the working chamber also increases, as a result of which the membrane is straightened under the action of a compressed spring. In this case, the transfer disk is lowered, which acts on the return spring, which, in turn, presses the valve into the seat. As a result, the supply of gas from the cylinder or gas pipeline to the working chamber is reduced, and accordingly, when the gas pressure in the pipeline decreases, a reverse reaction is triggered.
Scheme of operation of the reducer for direct (a) and reverse (b) gas. 1. Closing spring 2. Valve 3. Pusher 4. Diaphragm 5. Pressure disk 6. Spring
Classification depending on the scope of application
In general, all automatic pressure control devices can be divided into reducers for inert gases (nitrogen, argon, helium, etc.) and flammable gases (hydrogen, propane, methane, etc.). To avoid confusion, gearboxes are equipped with different threads.
Thus, reducers for flammable gases have a left-hand thread, and reducers for inert gases (including oxygen) have a right-hand thread.
- Oxygen reducers are used in work related to cutting, soldering and gas welding. Also used in medical institutions and for scuba diving.
- Acetylene gearboxes are used for cutting pipelines and gas welding. In addition, they are actively used in auto repair shops and service stations when carrying out body repairs.
- Propane reducers are used when carrying out work related to gas welding, cutting and heating. In addition, they are used to organize a high-quality supply of gas from cylinders to gas stoves, as well as in construction, in particular, when installing roofs using bitumen shingles.
- Air reducers are used to reduce air pressure in networks and various air communications; they are also in demand on submarines.
Features of using composite gas cylinders
This type of cylinders is an innovation among gas containers. Unlike their predecessors, composite cylinders have relatively less weight and are safer. When such a container explodes, no fragments are formed at all.
Another undeniable advantage of composite gas cylinders is the absence of corrosion processes inside. Along with this, a number of increased requirements are put forward for devices operated together with composite tanks.
The main task of the gas regulator when working together with composite cylinders is to maintain a stable pressure at the outlet within a given range. In conjunction with containers of this type, regulators are used that comply with European standards EN 12864.
As an example, we can cite the A300i-A310i device, which differs from the usual RDGS 1-1.2 in the following:
- Complete with a nut that can be tightened without much effort;
- Longer service life of the gasket under the valve, which is at least 10 years.
Design features include the presence of a spout recessed in the outlet hole and a circular collar placed in the valve seal. These design features are aimed at creating a better sealing of the connection.
At the same time, there is no need to confuse gearboxes with regulators for composite tanks, which, by creating optimal fuel supply pressure, regulate its consumption, measured in liters per minute.
The regulator can be used either as a universal type or as one made for a specific model of composite container. The optimal solution is to purchase a cylinder and regulator from the same manufacturer.
How to choose
One of the most common choices in this class of devices remains the RDGS-1 device, the main advantages of which are its affordable cost and simplicity of design. RDGS-1 is produced in Russia and Belarus; below are the main characteristics of the device:
- Input pressure value 0.07 – 1.6 MPa
- Output pressure 2950 – 3300 Pa
- Gas consumption 1.2 m3/hour
- Weight 310 g
- Operating temperature range -30°С +45°С
Reducer RGDS-1
Instead of the time-tested gearbox RDGS-1, the price of which is 150-200 rubles, you can buy a more modern model. For example, the Italian device m714, which costs a little more (about 250 rubles).
Typically, this reducer is supplied complete with a Pullover1 gas heater, but it can also be purchased separately. The gearbox is equipped with a gasket made of elastic material, which has a five-time use life. The input pressure of m714 is in the range of 0-20 Bar, and the output pressure is 30 mBar.
Often, to connect composite cylinders to burners, a German-made GOK model costing about 500 rubles is used. However, there are also more expensive models.
Thus, the N240 gearbox, which costs more than 1000 rubles, has the following characteristics:
- Inlet pressure up to 18 bar
- The output pressure can be adjusted within the range of 20 – 60 mbar
- Productivity – 4 l/hour
- Operating temperature range -20°С +50°С
Gearbox N24
Another type of gearbox, called miniature, has become widespread among gas cutters. A prominent representative of this class can be considered the BPO-5 general purpose gearbox, the main technical characteristics of which are:
- Input pressure value up to 2.5 MPa
- Output pressure value up to 0.3 MPa
- Weight 0.65 kg
It must be remembered that purchasing and installing a reducer for a gas cylinder is a serious and responsible step. Not only the quality of operation of gas appliances, but also the safety of everyone who will use this appliance largely depends on the correct choice.
The gas reducer in the gas supply system performs an important stabilizing function. Due to it, variable and high pressure is smoothed out to more or less constant, thereby ensuring normal and safe operation of the equipment.
Reducer "Frog" for a gas cylinder Gearboxes are used almost everywhere where gas equipment is involved, be it devices operating on flammable (methane, hydrogen, etc.) or inert (nitrogen, helium, etc.) gases. A typical household example is a gas cylinder reducer, also known as a "frog".
It is familiar to almost all owners of individual (autonomous) sources, who are forced to purchase them due to their distance from highways and, for this reason, lack of connection to a centralized gas supply. should remain at a pressure of about 15 bar, while for consumer devices the normal range is from 10 to 36 mbar.
If propane is not first passed through the reducer, the results of a direct connection may be a complete surprise to you. This is especially true for cylinders with compressed gas (for example, methane under a pressure of 250 bar). The “frog” is inexpensive, and it is easier to acquire one than to later spend money on eliminating the consequences of the disaster.
Motorists who have equipped their cars with economical gas equipment are also familiar with this device. Liquefied (or compressed) gas in such systems is also first sent to the propane-butane mixture (or methane) reducer, and then enters the carburetor or injector.
The gas reducer is also used in industry. In areas of transition from large highways to local networks, a significant reduction in pressure is required. Powerful and large-sized products are used here. Another example would be gearboxes for gas tanks involved in supplying industrial facilities or human settlements.
Classification
Legalizes the requirements for products GOST 13861-89. In particular, it establishes the classification of these devices given in table. 1.
Table 1
| Gearbox type | Maximum throughput V, m3/h | Maximum gas pressure at the inlet P1, MPa (kgf/cm2) | Maximum working pressure P2, MPa (kgf/cm2) | Weight, kg, no more |
| BKO-25 | 25 | 20 (200) | 0.8 (8) | 2.0 |
| BKO-50 | 50 | 1.25 (12.5) | 2.1 | |
| BKD-25 | 25 | 0.8 (8) | 3.5 | |
| BAO-5 | 5 | 2,5 (25) | 0.15 (1.5) | 2.2 |
| dietary supplement-5 | 3.6 | |||
| BPO-5 | 0.3 (3) | 2.0 | ||
| BVO-80 | 80 | 20 (200) | 1.25 (12.5) | 2.1 |
| SKO-10 | 10 | 1.6 (16) | 0,5 (5) | 1,8 |
| CAO-10 | 0.12 (1.2) | 0.1 (1) | ||
| SPO-6 | 6 | 0.3 (3) | 0,15 (1.5) | |
| SMO-35 | 35 | |||
| RKZ-250 | 250 | 20 (200) | 1.6 (16) | 13,0 |
| RKZ-500 | 500 | |||
| RAO-30 | 30 | 2.5 (25) | 0.1 (1) | 8 |
| RAD-30 | 10 | |||
| RPO-25 | 25 | 0.3 (3) | 8 | |
| RPD-25 | 10 |
As can be seen from the table, each device is designed not only to work for a specific purpose, but also for a specific gas. And if in the labeling and documentation of the product propane is indicated as a reducing gas, then only propane gas is allowed to be supplied to such a reducer, and an attempt to pass another gas (for example, methane) through it may be unsafe for health.
To avoid improper use, additional precautions are taken into the very appearance of the devices during manufacturing. Thus, gearboxes for flammable gases (for example, methane) have connecting elements with a left-hand thread, and for non-flammable gases (for example, nitrogen) - with a right-hand thread. Color highlighting is also used for differences.
You should also pay attention to the throughput, which determines the gas flow provided by the device. Before choosing a specific model, you should make sure that this indicator is sufficient for the consuming equipment used.
Design and operation scheme
The fundamental design of all gearboxes is similar. The weight and size characteristics of the components, their design features, etc. may differ. The operating pattern is similar to that observed in the float chamber.
In the cavity of the housing, which has inlet and outlet pipes, there is a membrane between two washers, balanced on top by a spring resting against the plane of the body, and on the bottom by a rocker arm pivotally connected to the inlet valve. At low pressure, the spring exerts enough force on the diaphragm that it holds the inlet valve open, allowing gas to pass through the device with virtually no resistance.
High pressure gas reducer diagram
When the pressure rises to a certain threshold value, the membrane begins to compress the spring, simultaneously covering the inlet valve with a rocker arm. The level of pressure required for these actions is determined mainly by the following parameters:
- membrane dimensions;
- spring characteristics;
- the force required to perform the work of closing the valve.
In this case, the propane reducer can be equipped with a mechanism for adjusting the operating pressure within certain limits, or manufactured without it (“frog” is an example of an unregulated option). Products designed to work as part of an automotive system are also customizable (methane ones usually have one regulator, propane ones - one or two).
The supra-membrane part of the housing may have an opening at the top and thus communicate with the environment. There are also sealed models. They lack a hole and a spring, and instead of the latter, the cavity is filled with gas, which ensures equilibrium with its pressure. Combination products are also available.
Here, the pressure of methane flowing through the reducer (for example) is regulated simultaneously by the influence of both the spring and the gas. The hole at the top in such gas trains performs the function of feedback. It connects the product to the volume into which the gas is directed, thus establishing the dependence of the pressure in the reducer on the pressure in the volume (i.e., the supply is proportional).
Setup and repair
It is possible to set up and repair a gas reducer yourself using available tools and a repair kit, but only if you know exactly what you are doing. Insufficiently qualified adjustment and assembly can lead to detrimental consequences. The main signs of abnormal operation of the product are as follows:
- deviation of outlet pressure from permissible limits;
- gas leak.
Pressure deviation is usually caused by a breakage or displacement of the spring, or the release of the compensating gas that performs its function due to depressurization of a part of the housing. But if the spring malfunction still needs to be eliminated using a repair kit, then the gas version falls into the non-repairable category (the entire device is changed).
Gas leakage can be caused by damage to the membrane, depressurization of the housing, or failure of the float valve. If the latter begins to leak gas, this may also manifest itself in the consuming product (for example, a gas water heater). Since the pressure at the output of the reducer is approximately equal to the input, then in the absence of flow (the consuming device is temporarily turned off), leakage will be inevitable.
Such a malfunction is difficult to diagnose because turning on the consuming device normalizes the situation. It can only be determined by measuring the gas pressure at the outlet of the reducer in the absence of consumption (as a rule, it should not exceed the nominal value by more than 20%).
Most problems can be eliminated by adjusting (modifying) the product or replacing some of its components with new ones taken from the repair kit.
But it is worth noting that gearboxes come in collapsible and non-dismountable (sealed) designs. The latter can only be replaced entirely.
So, having stocked up with the appropriate repair kit, the product must first be disassembled. By visually inspecting the spring and membrane removed from the housing, you should determine which of them caused the malfunction. A broken spring must be replaced with a new one from the repair kit.
If the spring is not broken, but simply compressed, having lost its elasticity over time, you can not change it, but simply select and place a gasket of the required thickness on the side of the body, without covering the existing hole.
If the membrane ruptures, it should be replaced using a similar one from the repair kit, but, as a rule, a tight connection with the washers enclosing it is not easy to make. Therefore, if you are unsure of your skill, think about the advisability of purchasing a new gearbox.
If the spring and membrane are intact, you should pay attention to the bypass valve.
This is a tube with a small hole, at the end of which a rocker arm is pressed through a rubber gasket. There are several common problems with valve operation:
- the normal movement of the rocker arm is disrupted;
- the rubber gasket is worn or damaged;
- the end of the tube is deformed.
Adjusting the valve is a simple process. The mobility of the rocker can be restored by turning or replacing its hinges. The damaged gasket should be cut off and replaced with a similar one in size from the repair kit. The roughness and evenness of the end of the tube, ensuring a tight fit of the gasket, is achieved by grinding it.
If the gearbox malfunction is a gas leak due to leaks in the contact areas of the membrane to the housing, then the damaged integrity can be restored using silicone sealant. When making adjustments or repairs or for any other reason not initially related to depressurization, it would be a good idea to also apply sealant in these places, which will prevent a similar problem in the future.
Upon completion of repair work, you must immediately check the tightness of the product using a soap solution. If there are no bubbles that indicate leakage, the gearbox should be re-tested after one day, then after a few more days. Subsequently, periodic monitoring (eg monthly) is recommended.
Like any other gas-related equipment, the reducer will serve you well if you select the right model and take simple steps to ensure safe operation. Periodic maintenance and timely detection of faults will save you from trouble.
The use of bottled gas requires a thorough approach to ensuring safety and ease of use. We propose to consider the simplest example of connecting a propane cylinder to a gas stove: connection diagram, shut-off and control valves, organization of storage conditions.
Where to install the cylinder
The main general requirement for the use of gas equipment can be called ensuring the safety of people. For this reason, gas cylinders are not recommended for installation in habitable rooms and technical rooms connected to a residential building directly or through ventilation.
A distinctive feature of propane gas is its high density. Bottled gas is heavier than air and can accumulate in the lower floors of buildings. Therefore, it is strictly forbidden to install cylinders in underground or technical rooms below ground level. If in the normal case small leaks do not pose a danger due to constant air exchange, then in the lowlands the gas can accumulate for a long time to explosive concentrations. Gas cylinders in accordance with SNIP 42-01-2002 can only be installed inside buildings no higher than 2 floors, in quantities of no more than one and at a distance of 0.5 m from gas stoves and 1 m from heating appliances.
To make the installation safer and prevent access to gas equipment by unauthorized persons, the cylinders are placed either in a room with a separate entrance or in an outdoor metal cabinet. It is especially important for outdoor installations to take into account the temperature conditions of operation. Bottled gas is a mixture of propane and butane, each of which has a different boiling point. When the cylinder is cooled below 0 °C, only propane will evaporate from the mixture, while the remaining butane in the cylinder cannot be efficiently used. At lower temperatures, it is possible to completely stop the flow of gas to the stove.
The main way to achieve normal operation at low temperatures is the use of so-called winter gas mixtures that can evaporate at temperatures down to -40 ° C. However, the problem is that such gas may be in seasonal shortage, and the possibility of filling with a mixture of mediocre quality cannot be ruled out. There are two ways to resolve the warranty issue: either insulate the attached metal cabinet, relying on heat penetration from the building, or additionally heat the cylinders using a self-regulating cable.
The height of the cabinet should be at least 20-30 cm greater than the height of the cylinders, so that they are not installed on the floor, but with a gap, for example, on two metal slats or a high pallet. In this case, the cabinet must be protected from the penetration of melt and rain water and heating from sunlight above 40 ° C.
Which gearbox to choose?
Gas stoves have built-in jets designed for constant gas pressure, while the pressure in the cylinder decreases with consumption. To normalize combustion, the cylinder is connected to the stove not directly, but through a reducer. Gearboxes for liquefied household gas are called propane and, as a rule, have a red or metallic body color.
The main characteristics of the gearbox - outlet pressure and throughput - must be selected to match the parameters of a single plate. If it is not possible to set the nominal pressure value, you should purchase an adjustable type reducer and set it manually. Also, adjustable reducers are directly indicated when using cylinders with a capacity of 20 liters or more, where the pressure drop is more pronounced.
For the use of propane for domestic purposes, gearboxes of the reverse operating principle are recommended. Due to the low pressure values of liquefied gas and the low difference at the inlet and outlet, the use of multi-stage gearboxes is economically unjustified. The only requirement is to use reducers provided for by their technical standard in conjunction with composite cylinders.
A separate nuance in choosing a reducer may be the temperature regime of the cylinders’ operation. The fact is that when liquid gas evaporates, an intense decrease in its temperature is observed. So, if initially the propane-butane mixture is at a temperature of -5...-10 °C, in the reducer itself its temperature can drop to the condensation mark, due to which the gas becomes liquid again and the reducer stops working. One way out of this specific situation is to use gearboxes with a built-in heating system.
What hoses and tubes to use for connections
According to the rules for the safe operation of gas equipment, oxygen and hydraulic hoses are not allowed to be used for laying gas pipelines. This is due to the high temperature difference between the transported gas and the external environment, which leads to accelerated degradation of the hose material and the appearance of microscopic leaks. Given the properties of liquefied gas to accumulate in rooms, such phenomena pose an increased danger.
There are three options for connecting a gas cylinder to a stove. The first is to use special flexible rubber hoses for flammable hydrocarbons. In this case, their connection to the gearbox is made through a standard fitting reinforced with a screw clamp. The same fitting is installed on the inlet pipe of the gas stove, the hose is connected to it also with a clamp. If it is necessary to connect two sections of hose, the use of double-sided fittings is not allowed; instead, threaded connectors with double crimping of the shank with clamps should be used. A distinctive feature of such connections for gas pipelines is the tapered thread and the absence of elastic seals.
Connecting the plate to the cylinder using flexible hoses has a number of limitations. The length of the hose should not exceed 150 cm, its gasket must remain visible to constantly monitor the condition of the sheath and avoid damage. Some of the prohibitions can be partially circumvented by using metal bellows hoses. They form a semi-rigid structure, which can have an almost unlimited extent, while maintaining resistance to temperature influences and mechanical damage.
At the same time, safety rules prohibit the passage of flexible and semi-flexible ducts through walls, where their condition cannot be assessed visually. If it is necessary to connect a kitchen stove to a cylinder installed outside, a steel pipe case should be embedded in a hole in the wall using cement mortar. Inside the case there is a steel tube of smaller diameter with threads at both ends; the space between the walls is filled with a plastic sealant, for example, polyurethane foam or silicone. Connection of bellows or flexible hoses must only be made through threaded adapters of the appropriate type.
Cranes and other fittings
A gas valve must be installed at the point where the gas pipeline is connected to the stove, blocking the gas supply in the event of a malfunction of the stove. This can be either a ball valve with a yellow handwheel or a gas plug valve. The disadvantage of the latter is the need for periodic maintenance.
Another useful addition to a gas pipeline can be a flow meter. Its inclusion in the transportation chain will help to respond in a timely manner to the depletion of the mixture in the cylinder and replace it. The metering device does not have to have the outstanding accuracy necessary to monitor gas consumption in main networks; a device costing up to 2 thousand rubles will be sufficient.
When connecting several cylinders at the same time, a connecting ramp can be used. Its installation helps reduce the rate of gas evaporation from each cylinder and makes the risk of freezing the mixture in the reducer less likely. Installation of the ramp can be done independently using any gas pipeline material.
Modification of the slab for bottled gas
Not every stove can initially run on liquefied gas. The main obstacle is the higher operating pressure, due to which there is a lack of oxygen in the burners, which is expressed in the yellow color of combustion and the appearance of soot.
The situation can be corrected by replacing the methane nozzles with nozzles for LPG. They have exactly the same form factor, but the hole diameter is slightly smaller. If you plan to connect a new stove, it will most likely come with a set of liquefied gas nozzles. If there are no replacement jets, they can be purchased at a reasonable price.
The diameter of the holes in the liquefied gas nozzles depends on the pressure in the outgoing chamber of the reducer and the power of the burner. Thus, the standard values for liquefied gas stoves are considered to be diameters of 0.43-0.6 mm for a pressure of 50 mbar and 0.5-0.75 for a pressure of 30 mbar. Individual cooker manufacturers may set their own diameters, and the use of nozzles with different hole diameters may void the warranty.
Replacing jets can be done in two ways, depending on the design of the plate. In the simplest version, it is enough to remove the burner body and look inside the seat sleeve. If a nozzle is visible at the bottom - a hexagonal head with a hole in the center - unscrew it with a 7 or 8 mm socket wrench and screw in the nozzle to replace it. If a cone with a hole is visible inside, you will have to remove the top panel by unscrewing several bolts on the sides from different sides. The nozzle itself in this design option cannot be unscrewed; it is pressed onto the stuffing box seals. You need to unclench the whiskers of the crimp coupling, move the nozzle down along with the supply tube, and then pull the nozzle out of the fitting and install a new one.
Commissioning of the plant
The entire installation of the gas pipeline is carried out without connecting it to the cylinder. When the tubes or hoses are connected to the stove and interconnected, the reducer nut is screwed onto the cylinder valve and tightened. Then, if a flexible hose is used, it is put on the fitting and crimped with a clamp. If bellows tubes are selected, the fitting must be unscrewed from the gearbox housing and a threaded adapter of the appropriate size must be screwed into it.
When the installation is assembled, you need to open the valve on the cylinder and, by rotating the reducer regulator, set the required outlet pressure. When the gas has entered the system of pipes and hoses, each connection is thickly coated with a foam-soap solution and checked for leaks. Once the integrity of the gas pipeline has been confirmed, you can open the stove tap and try to ignite the burners sequentially.
If each of them smokes or the flame burns in a color other than blue or greenish, it is necessary to reduce the pressure using the valve on the reducer. If the malfunction is typical only for some burners, it means that the jets for them are selected incorrectly. If the burner goes out in the minimum fire position, adjust the low flow screw on the stove tap or try to slightly increase the pressure with the reducer screw.