What types of check valves are available?
Check valve classification according to the material, function, structure can be divided into different types, the following small valve mall from these three aspects to introduce the type of check valve.
Check valves can be classified into those types
One, according to the material classification
Cast iron check valve
Brass check valve
Stainless steel check valve
Ii. Classification by function
1.NRVZ silent check valve
2.NRVG silent check valve
Check Valve: A Valve that automatically prevents backflow of fluid.The check valve disc opens under fluid pressure from the inlet side to the outlet side.When the inlet side pressure is lower than the outlet side, the disc will automatically close under the action of fluid pressure difference, gravity and other factors to prevent fluid backflow.
Check Valve: generally divided into lifting type, swing type, butterfly type and diaphragm type and other types.
Lifting type check valve structure is generally similar to the globe valve, its disc along the channel to the line for lifting movement, reliable action, but the fluid resistance is large, suitable for light small diameter occasions.Lifting type check valves can be straight through and vertical.Straight through lifting check valves can generally only be installed in the horizontal pipeline, and vertical lifting check valves are generally installed in the vertical pipeline.
The disc of a swing check valve rotates on a shaft.Its fluid resistance is generally less than the lifting type check valve, it is suitable for larger diameter occasions.Swing check valve according to the number of discs can be divided into single flap swing, double flap swing and multi - flap swing three kinds.Single - disc swing check valves are generally suitable for medium diameter applications.When choosing single flap swing check valve for large diameter pipeline, in order to reduce water hammer pressure, it is better to use slow closing check valve which can reduce water hammer pressure.Double disc swing check valves are suitable for large and medium diameter pipelines.The double-disc swing check valve has small structure and light weight. It is a fast developing check valve.Multi - flap swing check valves are suitable for large diameter pipelines.
Butterfly check valves are similar in structure to butterfly valves.Its structure is simple, the flow resistance is small, the water hammer pressure is also small.
Diaphragm check valve has a variety of structural forms, using diaphragm as the opening and closing parts, due to its good waterproof hammer performance, simple structure, low cost, rapid development in recent years.But the use of diaphragm check valve temperature and pressure is limited by the diaphragm material.
The valve mall
3.NRVR silent check valve
4.SFCV rubber flap check valve
DDCV double lobe backcheck valve
Check Valve: Standard swing Check flue Check Valve type dual flow Check Valve type
Slow closing check valve Vertical check valve quiet check valve price micro resistance slow closing check valve
Type H76 double-disc swing check valve has low water hammer pressure, short disc stroke, and spring assisted closing.
Fast closing speed
Type H44 flanged single disc swing check valve is large, long disc stroke, requiring a long closing time
The water hammer pressure of H76 is only 1/2~1/5 of that of H44
Ball type sewage check valve: the valve body adopts full channel structure, with the advantages of large flow and small resistance.Use ball as disc, suitable for high viscosity, suspended matter industry and domestic sewage pipe network.
Return valve: one-way valve: also known as the check valve or check valve, its role is to prevent the medium in the pipeline backflow.The bottom valve of water pump is also a check valve.
Open and close parts rely on the flow of media and force to open or close, in order to prevent the backflow of media valves called check valves.Check valves belong to automatic valves, mainly used for one-way flow of media on the pipeline, only allow the media to flow in one direction, in order to prevent accidents.
Three, according to the structure division
Can be divided into lifting type check valve, swing check valve and butterfly check valve three kinds.Lifting type check valves can be divided into vertical check valves and horizontal check valves.Swing check valve is divided into single - disc check valve, double - disc check valve and multi - disc check valve.Butterfly check valve for straight through check valve, the above several check valves in the form of connection can be divided into threaded connection check valve, flange connection check valve and welding check valve three.
Check Valve: Nominal pressure or pressure CLASS: PN1.0-16.0MPa, ANSI CLASS 150-900, JIS10-20K nominal diameter or diameter: DN15 ~ 900, NPS 1/4 ~ 36 Connection: Flange, butt welding, thread, socket welding and other applicable temperature: -196℃ ~ 540℃ Valve material:WCB, ZG1Cr18Ni9Ti, ZG1Cr18Ni12Mo2Ti, CF8(304), CF3(304L), CF8M(316), CF3M(316L), Ti.Choose different materials, check valve (AETV one-way Valve) : can be applied to water, steam, oil, nitric acid, acetic acid, oxidizing media, urea and other media.
General lifting type check valve should be installed on the horizontal pipe, vertical lifting type check valve and bottom valve are generally installed on the vertical pipe, and the medium flows from bottom to top.
Swing check valves are usually installed in horizontal lines, but may also be installed in vertical or dump lines.
Install Check Valve: when, should pay special attention to the direction of the medium flow, should make the normal flow direction of the medium and the direction of the arrow indicated on the Valve body, otherwise it will cut off the normal flow of the medium.The bottom valve should be installed at the bottom of the water pump suction line.
Check Valve (Check Valve) : when off, will be in the pipeline middle water hammer pressure, serious will lead to Valve, pipeline or equipment damage, especially for the big mouth pipeline or high pressure pipeline, so should cause Check Valve (AETV one-way Valve) : the high attention of the choice.