Types: Piston · Ball · Swing · Wafer · Grades: Stainless · Carbon · Alloy · Nickel · Classes: 150-2500 · Automatic non-return
Kalpataru Piping Solution supplies check valves, also called non-return valves or NRVs, which prevent backflow automatically. A check valve opens with forward flow and closes on reverse flow with no operator and no signal, protecting pumps, compressors and equipment from the damage reverse flow causes. We supply check valves in piston, ball and swing types and in stainless, carbon, alloy and nickel grades, as part of our full Valves range. Every valve is pressure tested before dispatch.
Because a check valve acts on its own, the type is chosen for how quickly and quietly it must close and for the service: a piston or ball check for small-bore and pulsating flow, a swing check for larger lines. The grade follows the process, from stainless for corrosion up to nickel alloys for aggressive media.
Check Valve Types
|
Type |
How it works |
Best for |
|
Piston / lift check |
A piston lifts off the seat with forward flow, drops back on reverse |
Small-bore, high-pressure and pulsating lines |
|
Ball check |
A ball is pushed off the seat forward, rolls back to seal on reverse |
Viscous and dirty service, small bore |
|
Swing check |
A hinged disc swings open with flow and swings shut on reverse |
Larger bore, low-drop lines |
|
Wafer check |
A thin spring-assisted disc between flanges |
Compact installation, fast closing |
Check Valve Grades & Ratings
Check valves are supplied in stainless 304 and 316, carbon steel, alloy and nickel grades, in classes 150 through 2500, with the disc, seat and spring matched to the service. The grade follows the line, and end connections are flanged, butt-weld, threaded or wafer. Instrument-scale check valves in tubing sizes are available for small-bore hook-ups.
Where Check Valves Fit
The classic place for a check valve is the discharge of a pump or compressor, where it stops the flow running back and spinning the machine in reverse when it stops. They also protect against backflow contaminating a supply, hold prime in a line, and sit downstream of a gate valves so isolation and non-return are both covered. The type is chosen so the valve closes fast enough to avoid slam yet freely enough not to restrict forward flow.
Quality, Testing & Certification
Every check valve is pressure tested, seat and shell, before dispatch, with an EN 10204 mill test certificate for the body material, heat-number traceable. Positive material identification confirms the grade, NACE MR0175 for sour service and third-party witness through BV, SGS or TUV are arranged at order stage. Common sizes ship quickly; higher classes and alloys are confirmed on enquiry. Send the type, size, class and grade and the quote comes back with the certification built in.
Check Valves: Frequently Asked Questions
Piston, ball, swing and wafer check valves in stainless 304 and 316, carbon steel, alloy and nickel grades, in classes 150 to 2500 with flanged, butt-weld, threaded or wafer ends. If a type, size or grade is not listed, ask, because we hold more than the site shows and can source to specification.
A check valve prevents backflow automatically. It opens with forward flow and closes on reverse flow with no operator, which protects pumps, compressors and equipment from the damage reverse flow causes and stops contamination running back into a supply. It is also called a non-return valve or NRV.
How they close. A piston or lift check has a piston that lifts off the seat with forward flow and drops straight back on reverse, which suits small-bore, high-pressure and pulsating lines. A swing check has a hinged disc that swings open and shut, giving a lower pressure drop, which suits larger-bore lines. The choice balances closing speed against pressure drop.
Match it to the process. Stainless 304 and 316 cover general and corrosion service, carbon steel suits standard process lines, alloy grades handle temperature, and nickel alloys handle aggressive media. The check valve should match the grade of the pipe and the other valves in the line.
Yes. Every check valve is seat and shell pressure tested before dispatch, and each order ships with an EN 10204 mill test certificate for the body material, heat-number traceable, with positive material identification, NACE documentation for sour service and third-party witness inspection available at order stage.