A pressure control is a control valve that reduces the input pressure of a liquid to the desired value of its output. Regulators are used for gases and liquids, and can be integral devices by adjusting the output, limiting and sensor pressures all in one body, or consisting of separate pressure sensors, controllers and flow valves.
Video Pressure regulator
Operation
The main function of the pressure regulator is to match the gas flow through the regulator to the gas demand placed on it, while maintaining a constant output pressure.
If the load flow decreases, the flow of the regulator must decrease as well. If the load flow increases, the flow of the regulator must increase to keep the controlled pressure from the drop due to the lack of gas in the pressure system.
The pressure regulator includes the limiting element, the load element, and the measuring element :
- The limiting element is a valve that can provide variable restrictions to flow, such as globe valves, butterfly valves, popet valves, etc.
- The loading element is the part that can apply the required force to the delimiter element. This loading may be provided with heavy, springs, piston actuators, or diaphragm actuators in combination with springs.
- The measuring element serves to determine when the incoming stream is the same as the outflow stream. The diaphragm itself is often used as a measuring element; it can serve as a combined element.
In the one-stage regulator drawing, the balance of power is used on the diaphragm to control the popup valve to regulate pressure. Without inlet pressure, the spring above the diaphragm pushes down on the popet valve, holding it open. Once the entry pressure is introduced, the open poppet allows the flow to the diaphragm and the pressure in the upper chamber increases, until the diaphragm is pushed upward against the spring, causing the child to reduce the flow, ultimately stopping the increase in further pressure. By adjusting the top screw, downward pressure on the diaphragm can be increased, requiring more pressure in the upper chamber to maintain balance. In this way, the outlet pressure of the regulator is controlled.
Single stage
High pressure gas from the supply goes into the regulator through the inlet valve. The gas then enters the body of the regulator, which is controlled by the needle valve. The rising pressure, which drives the diaphragm, closes the attached inlet valve, and prevents more gas from entering the regulator.
The outlet side is equipped with a pressure gauge. When the gas is pulled from the outlet side, the pressure inside the regulator body falls. The diaphragm is pushed back by the open spring and valve, allowing more gas to enter from the supply until equilibrium is reached between the outlet and spring pressure. Outlet pressure therefore depends on the spring force, which can be adjusted by handling adjustments or buttons.
Outlet pressure and inlet pressure hold the diaphragm/poppet assembly in a closed position against the large spring force. If the supply pressure drops, as if the compression of the large spring increases allows more gas and higher pressure to build in the outlet space until the equilibrium pressure is reached. Thus, if supply pressure falls, outlet pressure will increase, provided that outlet pressure remains under falling supply pressure. This is the cause of the end-tank dump in which the supply is provided by pressurized gas tanks. With one stage regulator, when the supply tank becomes low, the lower inlet pressure causes the outlet pressure to rise. If the spring compression is not adjusted to compensate, the poppet can remain open and allow the tank to dispose of the rest of its contents quickly. In other words, the lower the supply pressure, the lower the pressure differential the regulator can achieve for a given spring setting.
Double stage manager
Two-stage regulators are two one-stage regulators in one that operate to reduce pressure progressively in two stages instead of one. The first, prearranged stage reduces the supply gas pressure to the transitional stage; gas at that pressure goes into the second stage. Gas now appears at pressure (pressure work) is set by the pressure that adjusts the control buttons attached to the diaphragm. Two stage regulators have two safety valves, so if there is excess pressure there will be no explosion. The main objection to one-stage regulators is the need for frequent torque adjustment. If the supply pressure falls, the outlet pressure increases, thus requiring torque adjustment. In the two-stage regulator, there is automatic compensation for any drop in supply pressure. Single stage regulators can be used with pipe lines and cylinders. Two stage regulators are used with cylinders and manifolds.
Maps Pressure regulator
Apps
Air compressor
Air compressors are used in industrial, commercial, and home workshops to perform a variety of jobs including cleaning items; running an air powered device; and inflating items such as tires, balls, etc. Regulators are often used to adjust the pressure that comes out of the air receiver (tank) to match what is required for the task. Often, when one large compressor is used to supply compressed air for some uses (often referred to as "store air" if built as a permanent pipe installation throughout the building), additional regulators will be used to ensure that each separate device or function receives precise pressure needed. This is important because some air tools, or the use of compressed air, require pressure that can cause damage to other tools or materials.
Planes
Pressure regulators are found in pressurized aircraft cabins, pressure canopy seal controls, portable water systems, and waveguide pressure.
Aerospace
The aerospace pressure regulator has applications in propulsion pressure control controls for the reaction control system (RCS) and Attitude Control System (ACS), where high vibrations, extreme large temperatures and corrosive liquids are present.
Cooking
All modern pressure cookers will have pressure regulating valves and pressure relief valves as a safety mechanism to prevent explosions if the pressure regulator valve fails to release the pressure adequately. Some older models do not have a safety release valve. Most home cooking models are built to maintain low and high pressure settings. This setting is usually between 7 and 15 PSI. Almost all home cooking units will use a very simple one-step pressure regulator. The old model will only use a small weight above the opening that will sway to allow excess pressure to escape. The newer models usually incorporate a raised spring valve and allow pressure to escape as pressure in the vessel rises. Some pressure cookers will have a quick discharge setting on the pressure regulator valve which will basically lower the spring pressure to allow pressure to escape quickly, but remain secure. Commercial kitchens also use pressure cookers, in some cases using oil-based cooking stoves for fast-fried fast foods. In this case, and in the case of home cooking, pressure vessels can be used to cook food much faster than it takes to cook large quantities of food without pressure. Such pressure vessels can also be used to sterilize small amounts of equipment and in house canning operations.
Water pressure reduction
Often, water enters the water using equipment at fluctuating pressure, especially in remote locations, and industrial settings. This pressure must often be kept within range to avoid damage to equipment, or accidents involving pipe/drainage channels. The one-stage manager is sufficient because of the high fault tolerance of most of the equipment. Also used in applications where the reservoir water supply is significantly higher in altitude to the end of the line. such as underground mine water supply.
Oxy-fuel welding and cutting
The oxy-fuel welding and cutting process requires gas at certain pressures, and regulators will generally be used to reduce high-pressure storage cylinders to be used for cutting and welding. The gas-oxy regulator usually has two stages: The first stage of the regulator releases gas at a constant level of the cylinder even though the pressure in the cylinder becomes less when the gas is released. The second stage of the regulator controls the reduction of pressure from medium pressure to low pressure. This is a constant stream. The valve assembly has two pressure gauges, one showing the cylinder pressure, the other showing the hose pressure.
Propane/LP Gas
All propane and LP Gas applications require the use of regulators. Since the pressure in the propane tank can fluctuate significantly, the regulator must be present to provide stable flow pressure to the downstream equipment. This regulator usually compensates for tank pressure between 30 - 200PSI and generally provides 11 inch (0.4 PSI) water column for residential application and 35Ã, inch water column (1.3 PSI) for industrial applications. Propane regulators differ in size and shape, delivery pressure and adjustment, but are uniform in their objective to provide constant outlet pressure for downstream requirements. As in all regulators, the outlet pressure is lower than the entry pressure.
Gas-powered vehicles
No matter what type of motor (internal combustion engine or electric fuel cell powertrain) special pressure regulator will be required to carry stored gas (CNG, Hydrogen) pressure from 700, 500, 350 or 200 bar (or 70, 50, 35 and 20 MPa) for operating pressure in handling all safety and operational requirements.
Recreational vehicles
For recreational vehicles with pipes, pressure regulation is a must. When camping, the water source may have a very large pressure level, especially if it comes from a tank located at a much higher altitude than the camp. The water pressure depends on how far water should fall. Without pressure regulators, the strongest pressure encountered in several campsites in the mountains might be enough to blow up the camp water pipes or shift the pipeline, causing flooding. The pressure regulator for this purpose is usually sold as a small screw accessory corresponding to the hose used to connect the RV to a water supply, which is almost always screw-thread-compatible with a public garden hose.
Air supply breathing
Pressure regulators are used with air tanks for SCUBA dive. The tank may contain more than 2,000 PSI pressures, which can cause a fatal barotrauma injury in someone who breathes in person. The regulator allows only continuous airflow at ambient pressure (which varies based on depth in water).
Mining Industry
Due to very rapid pressure in relation to depth, underground mining operations require fairly complex water systems with pressure-reducing valves. This device must be installed at intervals of a certain distance, usually 600 feet (180 m). Without such valves, the pipe will break easily and the pressure will be too large for equipment operation.
Oil and gas industry
See also Blow Out Preventer
References
External links
- Pressure Animation
Source of the article : Wikipedia
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