A reducer is an obligatory component of the connection scheme for tanks with liquefied and compressed gas mixtures. They are installed on gas holders, single cylinders and balloon installations to stabilize and bring to standard values the pressure of gas supplied to household equipment, welding torches and heaters.
It happens that during operation, the device for ensuring stable pressure begins to make noise. We will tell you why the gearbox buzzes on a gas bottle, we will analyze why the sound appears. We will show you how to eliminate violations in the operation of the device, which can be determined “by ear”.
In the article we presented, the types of gas pressure stabilizers and their design features are described in detail. Methods of restoring full working capacity are given. Our recommendations will help home craftsmen cope with repairs on their own.
Gas Pressure Reducing Devices
The need for the use of reducers is due to the difference in gas pressure in the tanks intended for storage and dosed supply of gas to the devices, and the operating parameters of the pressure required by these devices to perform their duties. When selecting fuel from a closed tank, the pressure of the gas mixture must be reduced by a dozen or more times.
Reducing the pressure of liquefied or compressed gas sweep to performance is the main work of the gearboxes. In addition, they automatically maintain the gas flow pressure within the limits required for normal operation. And they also protect the gas tank from the back impact possible with the activation of the flame.
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A reducer is an obligatory component of the scheme for connecting gas equipment to an autonomous gas source - a cylinder, an installation from a group of tanks, a gas tank
The task of the gearbox is to lower the pressure with which the vapor of the liquefied gas mixture is supplied from the tank
In the simplest models of reducers for gas tanks there are no complex technical units. There are either no adjustments at all, or they are primitive mechanical
The devices that regulate the gas pressure are so simple that the location on the street and work in any weather absolutely do not affect their work
Pressure regulators for standardized gas supply from a cylinder are produced for steel and composite containers. They vary in terms of pressure reductions.
Reducers are installed on all types of gas cylinder installations, including two or more cylinders, one or two arms, one of which is a backup
The gearboxes are more complex in design at the outlet of the gas tank. They perform a two-stage vapor pressure reduction of liquefied gas mixtures
Regulators are mounted not only for servicing stationary equipment, but also for supplying gas with standard pressure to gas burners, heaters, stoves
Gas bottle with inlet reducer
Pressure reducer with pressure gauge
Simple frog model
The location of the gearbox with a cylinder on the street
Compressor Pressure Regulator
Gas cylinder installation with gearbox
Gas tank control devices
Gas supply to the mobile gas stove
With the help of gearboxes, gas pressure is regulated.They can be configured to supply a gas medium with pressure parameters that are acceptable literally for any type of household and industrial equipment. Despite an extensive list of functions, structurally, all types of devices are simple, and even work on a similar principle.
Types of gas reducers
In order to understand why a gas cylinder began to make noise, it is necessary to study its structure. We will analyze what types of gearboxes for adjusting and stabilizing the pressure of gas mixtures are used in everyday life.
Classification is performed according to the following grouping criteria:
- Principle of operation. Gearboxes are direct and reverse. The former reduce pressure in the tank itself and in front of the nozzle connected to the gas equipment. The second - first lower the pressure in the cylinder, then at the exit from it.
- Destination There are network (C), balloon (B) and ramp (R) devices. The network ones are mounted on gas supply pipelines, the ramp ones are mounted on balloon installations, which ensure the supply of gaseous fuel in large volumes. For domestic conditions and one-time welding work, balloon models are suitable.
- Type of reducible gas. Pressure stabilizing devices are installed on all types of gas cylinders. To accurately select the necessary gearbox, they are painted in the colors of the container. For tanks with propane, red is produced, for tanks with oxygen blue, for tanks with acetylene, white.
- Regulation scheme. The installation of the operating pressure parameters can be carried out and adjusted mechanically, such devices are single-stage (O) and two-stage (D). Gearboxes with pneumatic pressure selection are only single-stage.
- Connection. Reducers are produced for installation on cylinders with combustible and non-combustible gases. The devices are connected to containers with oxygen with union nuts with a right-hand thread, to cylinders with a propane-butane mixture - nuts with a left-hand thread. The acetylene reducer is connected using a clamp and a thrust screw.
Let's analyze and study the design with the principle of operation of gas reducers, traditionally used in everyday life to regulate the flow of a gas mixture to devices.
Design features and principle of operation
Summer residents and owners of small private houses to supply gas to stoves, heaters and heating boilers use one of the most common gas reducer models in everyday life: NZGA RDSG-1-1.2, popularly known as the “frog”, or its analogues.
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Pressure regulator of liquefied gases RDGS-1-1,2
Overall dimensions of the device
Connection of balloon gas reducer
Conditions for normal gear operation
The one-stage model is extremely simple. Reduction is carried out by a membrane pressed from the outside by a spring. The membrane limits the path for the gas to move through the cavity of the device so that a stream with a given volume and standard pressure enters from the outlet in the gas hose or pipe.
If the pressure in the cavity of the gearbox rises, the valve and washer associated with the membrane rise and cover the inlet. This is how pressure stability is ensured. And if necessary, change the operating characteristics of the pressure, these control elements are displaced, increasing or decreasing the cross section of the inlet.
The frog-type pressure regulator usually begins to make noise due to damage to the membrane or loss of tightness if it is displaced
In slightly more complex devices, for example, in the model FL92-4 PS, the reduction is carried out by a valve that restricts the flow and thereby forms the pressure required by the devices.
The membrane in such devices does not directly participate in the formation of pressure, but only reduces the initial parameters.On it, on the one hand, a gas flow acts, on the other, a coil spring, which is pressing from below.
A pressure gauge is required in the gearbox connection schemes with the ability to adjust the gas pressure. It is needed to control the set parameters and monitor the state of the gas mixture in the tank
These devices are characterized by a certain pressure loss as the consumption of blue fuel in the tank with the gas mixture. Therefore, the housing has an adjustment screw that allows you to adjust the performance. In order not to make a mistake with the adjustment, such models are equipped with pressure gauges.
In more complex models of gearboxes, the pressure characteristics of the gas mixture required for operation are set by both the bending diaphragm and the opening valve
In devices of the third type, for example, TECH CONTROL of the OX OR-128 series of the Svarog 95255 brand, the reduction and stabilization of the pressure characteristics is performed due to the simultaneous movement of both the valve and the membrane.
The gas flow entering the cavity of the gearbox is on the one hand held and controlled by a valve, and on the other hand, a membrane supported by a spring with a transfer disk.
Two pressure gauges are used to control pressure parameters in control devices with a working valve and a membrane. Mount them at the inlet and outlet of the gearbox
The operation of gears of the third type should be controlled by two pressure gauges supplied at the input and output of the device. They also tend to change the working pressure at the outlet of the gearbox as the gas source is empty.
Malfunctions and repair operations
We examined the structure of typical models of gas reducers and made sure that there are no technically complex assemblies in the design. Everything is so elementary that it’s not necessary to turn to gas workers to repair devices. Simple repair operations can easily be done with your own hands.
You just need to figure out in advance what to do so that the gas cylinder reducer stops buzzing.
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In order to independently determine the cause of a violation in the operation of the liquefied gas pressure regulator, the device will need to be disassembled
Often, the cause of noise in the gearbox, which appeared due to deformation or displacement of elements, can be eliminated in the process of banal sorting and cleaning
The parts of the regulator that have received serious damage, cracks, chips, breaks must be changed using repair kits of the same production as the gearbox
To replace the gearbox diaphragm, a similar element can be cut out of rubber-fabric material with exact observance of size and shape
Dismantling the gas pressure regulator
Cleaning and replacing sealing elements
Gearbox thread breakage
Damaged gas reducer diaphragm
The causes of noise in a reduction device include:
- Deformation and damage to the elastic working element (membrane) of the device, which is often caused by excess pressure of the gas mixture at the outlet of the cylinder or gas tank.
- Incorrect operation. Most often, due to inaccurate and illiterate actions in the process of self-regulation, the spring or the membrane is damaged.
- Preparation for supplying low-quality, poorly cleaned gas mixture to gas appliances.
Often, at the initial stages of the appearance of noise in the gearbox, it is enough to simply adjust the factory settings. However, we note that the “frog” refers to unregulated devices; in any case, it will have to be repaired. Repair is carried out by banal replacement of damaged parts: a membrane, an end face of a bypass valve or a spring.
How to change the membrane?
To replace the membrane, it is better to use a repair kit, commercially available from the manufacturer of the gas reducer.This elastic element belongs to the abradable and periodically worn category, because manufacturers of expensive gearboxes supply replacement parts for sale.
In order to competently carry out repairs and change damaged parts, you need to thoroughly study the device using the technical documentation attached to the product
If you do not have a membrane for your gearbox brand, then you need to find out the following characteristics:
- Dimensions of the rubber-fabric diaphragm (membrane).
- The thickness of the oiled elastic web of which the membrane is made.
- The location of the fixation points around the circumference of the membrane.
Data can be found in the technical documentation for the device or obtained as a result of trivial measurements.
One of the typical causes of a malfunction in the gas pressure regulator from a cylinder is a loss of tightness in the area of the membrane or its damage
It happens that the sound in the gearbox does not appear due to a torn or deformed membrane, but because of a loss of tightness between it and the body.
In this case, the gearbox is quite simple to sort out. Before reassembling, the parts of the housing that are in contact with the membrane must be lubricated with sealant, then the components must be connected, making the diaphragm fit perfectly to the rigid base.
How to fix a reducing spring?
The process of replacing a compression valve or spring diaphragm is no more complicated than installing a new diaphragm. In the design of the gearboxes used in schemes with gas cylinders, reduction springs of the first degree, Ø 15,5 with a number of turns of 12-14 pieces are used.
Springs are used in the construction of all types of gas gears. They are in elementary unregulated “frogs” and in more complex devices with adjusting devices
The spring during operation can crack corny, lose firmness and elasticity, stretch. Due to any of these malfunctions, the membrane and the inlet valve will not be able to balance their force, i.e. control over the flow of gas into the gearbox will be lost.
In the event of a spring breakdown, it is replaced with a completely similar part. If it is just a little stretched, the problem is solved by installing a gasket. The thickness of this seal is selected based on the situation, measuring the necessary distance to reduce the fact.
How to change the reducing valve?
This work is more serious than the previous steps. An important functional part of the gearbox is connected with an adjusting screw, the position of which determines the gas pressure. A spring compresses it, which with excessive force can easily be damaged.
In addition, the valve may not be able to cope with the duties due to damage or deformation of the end of the tube resting on it. The course of the rocker arm may be disturbed, the movement of which is prevented by any shifted or damaged part. Still malfunctioning of the valve are observed due to wear of the gasket.
In the device of pressure regulators for compressed gases used in everyday life mainly for gas welding and metal cutting, similar structural elements are used
Naturally, in order to restore valve operability, it will be necessary to disassemble the gear housing. The mobility of the beam is ensured by replacing the displaced parts. If necessary, grinding the edge that interferes with free travel.
It often happens that all violations in the operation of the valve are associated with just a leaky gasket. Because of it, the elements of the device slightly change their position, but even fractions of millimeters are reflected in the functionality of such a sensitive device. "Treated" by installing a new gasket.
If the end of the tube is damaged, you just need to grind it. If the tube or rocker is seriously damaged, then it is better to change them.Replacement is carried out using repair kits produced for the maintenance and repair of gas valves.
The video introduces the recommendations for choosing a frog-type gearbox:
Video presentation of propane gearbox with pressure gauge:
It should be remembered that the inspection of the technical condition and repair of fittings for gas appliances should be carried out by gas service providers involved in the supply of blue fuel and equipment maintenance. However, the simplest operations can be handled independently. This happens, for example, if it is difficult or impossible to call a gasman to the cottage.
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