Spool valve Directional controls

Directional spool valves comprise a moving spool situated in the valve housing. When an actuating force moves the control spool, the annular channels in the housing are connected or separated. Directional spool valves have several unique features, such as high switching power, low actuating force and a wide variety of control functions.

Directional spool valves may be direct-operated or pilot-operated. A direct-operated spool valve is either electrically controlled with solenoids, mechanically (e.g. manually) controlled with levers or rollers, or controlled with hydraulics or pneumatics. Whether a directional spool valve is direct- or pilot-operated depends on the actuating force needed to move the spool. Thus, this is dependent on the flow, i.e. nominal size of the directional spool valve.

When valves are operated at higher hydraulic system operating pressures, leakage losses around the spool and the housing should be taken into account, especially at system pressures over 350 bar. The leakage loss is determined by the size of the gap between the spool and the housing, the viscosity of the hydraulic fluid and the hydraulic system 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).