A gas reducer is used to reduce the gas pressure at the outlet of the gas pipeline or any container. The device automatically maintains the working pressure, despite the jumps in the line. The design of the device can be simple or combined, depending on the model and the task at hand. Groups of devices have a wide range of settings and bore diameters, so the adjustment of the gas reducer affects the operation of the supply system.
Device and principle of operation
An autonomous regulator coordinates pressure without involving an additional energy source. Devices are divided by purpose, method of operation of the valve, the nature of the action, the method of setting.
Standard Features:
- case made of metal or PVC;
- connecting pipe with nut;
- working union;
- filtering unit;
- dual chamber with a central membrane;
- valve seat on the axle;
- manometer.
Valves are one and two-seat, diaphragm, the design uses hose valves, cranes and butterfly valves. Membranes of the first two types are placed in city highways. They are sealed with rigid gaskets made of metal, rubber, fluoroplastic.
The principle of operation of the gearbox is directly related to its type. Direct-acting devices reduce operating pressure as fuel is consumed from the tank. Reverse type devices show an increase in working pressure with a decrease in gas volume.
Gear Classification
According to GOST 13.861 - 1989, gearboxes are classified by location in the system and purpose, there are ramp, balloon, network. The transmitted gas is divided into hydrogen, propane-butane, acetylene, oxygen, methane.
By the number of steps, changes are classified into types:
- single-stage with spring pressure adjustment;
- two-stage with spring pressure supply;
- single-stage with pneumatic method of pressure setting.
Gas regulation in the highway with significant flow rates is carried out by single-stage devices. A two-stage pressure reduction is used to eliminate inlet vibration and to eliminate fuel consumption for the stability of the device. Such a system is installed in house gearboxes, which allow up to 25 m3 / h and are used by individual consumers.
Household unregulated
In flow reducers, the pressure decreases with the separation of the incoming stream into small jets inside the box. Non-regulated ones perform the function of setting the gas, stabilizing the oscillations of the fuel supplied from the cylinder. The regulator has a simple design and is used to maintain operating pressure when supplying gas to household appliances.
Domestic gearboxes have a low flow characteristic and are configured for low or medium inlet head. Pressure ensures the safety of working with gas in the house and apartment and is calculated on the supply of fuel to boilers, stove burners, and ovens.
The design of an unregulated household appliance combines:
- shut-off safety valve;
- safety relief valve;
- filter;
- silencer
In devices with pneumatic pressure control, the gas equipment is adjusted at the output of the device or by the external pulse connection method.The point of sampling of the external stimulus is connected in the region of steady flow in the absence of pressure surges and turbulences.
Universal adjustable
Devices for commerce and industry are distinguished by a wide variety of input and output parameters and work in different sectors of the economy.
Simple models have 1 reduction stage, combined models have 2 stages. Sometimes in composite types, the passage of the main controller and optionally the screen controller are provided. Universal types work reliably due to step reduction, independence from pressure drops at the inlet and outlet.
You can configure performance indicators by categories:
- high - medium;
- high - low;
- medium - low.
Gearboxes protect the consumer from gas supply under high pressure due to the integrated UCS and PZK (relief and safety valve). The monitor regulator sets a regular fuel supply in the event of a breakdown in the main regulator. Spring-loaded gearboxes respond quickly to changes in pressure, are characterized by a small flow diameter and operate within a narrow framework of the outlet pressure. Pilot types allow up to 10 - 30 thousand cubic meters per hour, but the transition speed is reduced compared to spring models.
Professional
A two-stage regulation system implies that a high pressure reducer is placed on the cylinder, and a low-pressure device must be installed at the consumer. Gas equipment can be adjusted with single-stage devices with an accuracy of up to 1 kPa, but professional gearboxes can be set to work with an accuracy of 0.25 kPa. Such requirements are imposed on the pipeline of high-performance gas installations for stable ignition of burners and uniform flame.
The appropriate type of regulator is selected taking into account the total power of the connected equipment, the total load is calculated according to the passport data of each consumption point. Professional gearboxes reduce the pressure at the first stage of the LPG during intake from the tank, maintain low rates, regardless of vibrational pulses.
Features of the use of gas reducers
Oxygen reducer is often used in industrial engineering, metallurgy for gas welding. Devices are used in underwater operations and the medical field. Propane-butane species are placed in the gas line at enterprises, construction sites and in everyday life. In them, the working pressure is adjusted at the factory, but it is possible to adjust the gas pressure reducer during installation. Acetylene devices are used in the utility sector for cutting and welding pipes.
There are gearboxes that can regulate non-combustible and combustible gas mixtures. Devices for working with hydrogen and methane differ in left-hand thread so that they cannot be accidentally connected to an oxygen tank. Oxygen regulators have a right-hand thread and are connected to cylinders of nitrogen, helium, nitrogen (inert gases).
Adjustment and regulation of gas
The working mechanism contains a control element in the form of a sensitive device for comparing the pulses of the setpoint and the coordinated pressure indicator. The node receives a command, drives the control shutter due to the action of the working medium.
Depending on the type of regulation, gearboxes are distinguished:
- static
- astatic;
- isodromic.
If the movement force is large, the sensing element controls a direct-acting regulator using a spring. The energy of the moving gas can also act as a pressure gauge. The device gives a command to the actuator in the form of a coordinating pressure - such reducers are called pilot.
Criterias of choice
Gas consumption should not exceed the performance of the device. The upper flow rate of the gas reducer is not standardized. For example, for a 24 kW boiler with a flow rate of 2.5 kg / h, a controller is installed with a capacity of more than 3 kg / h, because the automatic system of the unit will not let in excess gas.
Take into account indicators:
- type of gas mixture;
- connection method to the circuit;
- outlet pressure plug and working pressure;
- maximum performance or gas consumption;
- operating temperature range.
The operating regulations of most household appliances is 20 - 50 megabars. If the pressure is very different from the same parameter for the grill, gas stove or oven, the equipment will not work properly and a dangerous situation will arise.
The rules of operation of gas reducers
The manual contains a rule on preliminary checking the gearbox for proper operation before starting operation. It is necessary to observe the frequency of verification of the device by the relevant services. The valve opens for checking and the readings of the arrow are read. Operating parameters are set according to the low pressure gauge. Adjustment is made by slowly turning the valve.
Not recommended:
- work with welding near existing equipment;
- check for leaks with a burning match;
- heat the gearbox when freezing with an open flame;
- establish regulators for other purposes;
- use inappropriate pressure gauges.
It is impossible to establish operational indicators at the closed crane. If the gearbox is frozen, it is heated with steam or hot liquid with the valve closed and the tank isolated. Do not use the regulator with visible damage to the case.
