Check valve Directional controls

A check valve is the simplest type of directional control valve used in hydraulic systems. Check valves stop the flow of fluid in one direction and allow free flow in the opposite direction. They are also known as non-return valves. Check valves may be used as prefill valves, bypass valves, pre-tensioning or protection of hydraulic components against pressure surges.

Most check valves are spring-loaded and use a ball or plate to seal the flow in one direction. Check valves are designed with seats and thus are able to isolate circuits with no leakage. Balls, plates, poppets or poppets with soft seals are used as isolating elements.

There is a special type of check valve that prevents pistons or cylinder plungers from coming down and causing accidents. This is called a line rupture valve. When the line ruptures, the flow through the line rupture valve increases substantially, causing an increased pressure drop. This in turn creates a stronger force on the ball, which will close immediately.

Other special types of check valves are pilot-operated check valves and shuttle valves. A pilot-operated check valve allows flow in either direction by application of an external pilot pressure signal. A shuttle valve permits free flow at the highest operating pressure.

Damen Technical Agencies, B.V., also known as DTA Hydraulics, is a highly-specialised engineering sales company with core competence in hydraulic parts, equipment and machinery.

DTA has been serving your industry with the supply of hydraulic parts, components and as a Parker distributor hydraulics for more than 30 years. In 2010 we were fully qualified and certified as a distributor of hydraulics by Parker Hannifin. Together we developed a rapid delivery program for the genuine Denison Hydraulics Vane Technology.

DTA can be your one-stop-shop and supplies high-quality brands only such as Parker Hannifin (Denison Hydraulics, Olaer, Calzoni, VOAC, Sterling Hydraulics), Bosch Rexroth (Brüninghaus, Eppensteiner, Hägglunds, Hydromatik, Oil-Control), Bucher Hydraulics, Moog, STAR Hydraulics, Hydac and Eaton (Char-Lynn, Eaton Hydraulics, Integrated Hydraulics, Vickers).