Ball check valve

Ball check valves are often very small, simple, and cheap. They are commonly used in liquid or gel minipump dispenser spigots, spray devices, some rubber bulbs for pumping air, etc., manual air pumps and some other pumps, and refillable dispensing syringes. Although the balls are most often made of metal, they can be made of other materials, or in some specialized cases out of artificial ruby. High pressure HPLC pumps and similar applications commonly use small inlet and outlet ball check valves with balls made of artificial ruby and seats made of artificial sapphire, both for hardness and chemical resistance. After prolonged use, such check valves can eventually wear out or the seat can develop a crack, requiring replacement. Therefore, such valves are made to be replaceable, sometimes placed in a small plastic body tightly-fitted inside a metal fitting which can withstand high pressure and which is screwed into the pump head.

Diaphragm check valve

A diaphragm check valve uses a flexing rubber diaphragm positioned to create a normally-closed valve. Pressure on the upstream side must be greater than the pressure on the downstream side by a certain amount, known as the pressure differential, for the check valve to open allowing flow. Once positive pressure stops, the diaphragm automatically flexes back to its original closed position.

Swing check valve

A swing check valve is a butterfly-style check valve in which the disc, the movable part to block the flow, swings on a hinge or trunnion, either onto the seat to block reverse flow or off the seat to allow forward flow. The seat opening cross-section may be perpendicular to the centerline between the two ports or at an angle. Although swing check valves can come in various sizes, large check valves are often swing check valves.

Clapper valve

A clapper valve is a type of check valve used in firefighting, and has a hinged gate (often with a spring urging it shut) that will only remain open in the outflowing direction.

Lift-check valve

A lift-check valve is a check valve in which the disc, sometimes called a lift, can be lifted up off its seat by higher pressure of inlet or upstream fluid to allow flow to the outlet or downstream side. A guide keeps motion of the disc on a vertical line, so the valve can later reseat properly. When the pressure is no longer higher,

Stop-check valve

Distributor of check, angle, stop-check, non-return, blow-off & blow-down valves for steam boiler applications. Stop check valve products available include features such as all 316 stainless steel construction, teflon packing & gasket, "T" pattern, raised face ends & optional 90 degree angle...

Plastic check valves

The patented diaphragm in the Plast-O-Matic True Blue Check Valve is designed to re-seat with a bubble tight seal regardless of mounting position or reverse flowUnsurpassed performance in a plastic check valve. Patented diaphragm design provides the ultimate normally-closed, zero reverse-flow valve. Available pipe sizes 1/2" 3/4" and 1". Body materials are Geon® PVC, Corzan® CPVC, Glass-filled polypropylene, and Kynar® PVDF. Seal materials are EPDM and FKM.

Brass check valves

Our Company's solid brass check valves perform in a variety of fluid-handling environments by preventing fluids from flowing backwards, especially into pumps. Use of check valves also allow maintenance to be performed down line without losing pressure in the system ahead of the maintenance.

Stainless steel check valves

This group manufactures Bronze, Iron, Steel, and Stainless Steel Gate, Globe, and Check Valves traditionally sold for general services into Commercial Construction (HVAC), Chemical Refining, Petroleum Refining,Power Generating, and Pulp and Paper industries.   

Hydraulic check valves

Check, Hydraulic directory on the Internet. A broad range of Valves: Check, Hydraulic resources are compiled in this industrial portal which proves information on manufacturers, distributors and service companies in the Valves: Check, Hydraulic industry.

Wafer check valves

All-plastic construction of Hayward Wafer Check Valves ensures these valves will never jam or stick because of rust or corrosion. They will not contaminate sensitive process fluids they come in contact with, and require no painting or coating to stand up to corrosive environments.