The purpose of using check valves is to prevent the flow of the medium, generally in the export of the pump to install check valves. In addition, check valves should be installed at the outlet of the compressor. In general, check valves should be installed in equipment, units or lines to prevent media reflux.
Vertical lift check valves are generally used in the nominal diameter of 50mm horizontal pipeline. Straight-through lift check valves can be installed in both horizontal and vertical lines. The bottom valve is generally only installed in the vertical pipe of the pump inlet, and the medium flows from bottom to top.
Swing check valve can be made to a high working pressure, PN up to 42MPa, and DN can also be very large, up to 2000mm. According to the material of the shell and seal, it can be applied to any working medium and any working temperature range. Medium is water, steam, gas, corrosive medium, oil, food, medicine and so on. The working temperature of the medium is between -196 ℃ and 800℃.
Swing check valves are usually installed in horizontal lines, but can also be installed in vertical or inclined lines.
Butterfly check valve is suitable for low pressure and large diameter, and installation occasions are limited. Because the working pressure of butterfly check valve can not be very high, but the nominal diameter can be very large, can reach more than 2000mm, but the nominal pressure is below 6.4mpa. Butterfly check valves can be made into a wafer type, generally installed between the two flanges of the pipeline, using the form of the clamp connection.
Butterfly check valves can be installed in a horizontal, vertical or inclined line.
Diaphragm check valve is suitable for easy to produce water strike pipeline, diaphragm can be very good to eliminate the medium countercurrent water strike. Because the working temperature and use pressure of diaphragm check valve are limited by diaphragm material, it is generally used in low-pressure normal temperature pipe, especially suitable for water pipe. General medium working temperature between -20~120℃, working pressure < 1.6mpa, but diaphragm check valve can do larger diameter, DN up to 2000mm above.
Diaphragm check valve because of its excellent waterproof performance, relatively simple structure, low manufacturing cost, so in recent years, more applications.
Because the seal is a rubber coated ball, the ball check valve has good sealing performance, reliable operation and good water strike resistance. And because the seal can be a single ball, and can be made into more balls, so it can be made into a large caliber. But its seal is covered rubber hollow sphere, not suitable for high pressure pipelines, only suitable for middle and low pressure pipelines.
Because the shell material of the spherical check valve can be made of stainless steel, and the hollow sphere of the seal can be coated with polytetrafluoroethylene engineering plastics, it can also be used in the pipeline of general corrosive media.
This type of check valve operating temperature between -101 ℃ to 150℃, its nominal pressure ≤4.0MPa, nominal diameter range between 200~1200mm.
Nortech is one of the leading industrial valve manufacturers in China with quality certification ISO9001.
Major products: Butterfly Valve, Ball Valve,Gate Valve, Check Valve, Globe Vavlve,Y-Strainers, Electric Acurator , Pneumatic Acurators .
Post time: Oct-14-2021