Small valves handle big flows
Hydraulic engineers, like those engaged in most other branches of the profession, are always looking for ways to save space and weight without compromising performance.
Problem:
Solution: The GS02 range of solenoid operated, bi-directional poppet valves from Sterling Hydraulics have bodies less than 100mm high, but can handle flow rates up to 58 litres/min. Pressure ratings are up to 210 bar pressure in the case of the GS02 80 and 350 bar in the case of the GS02 81.
When the solenoid is de-energised, the spring behind the armature holds the pilot spool against its seat. Pressure on either port acts behind the poppet, holding it firmly closed. When the solenoid is energised, the armature pulls the poppet off its seat. Pressure acting on either port creates pilot flow through the poppet and pilot stage. This causes a pressure imbalance that lifts the poppet fully.
The coil is waterproof and hermetically sealed. It requires no 'O' rings. The coil can be reversed without affecting performance. Suitable fluid is either mineral oil or synthetic fluid with lubricating properties. Built-in thermal relief is set at 36 bar above rated pressure. Opening and closing response time is 40ms. Maximum internal leakage is 0.33ml or 5 drops/minute. The cartridge weighs 140g and the coil, rated at either 14W for the model 80 or 19W for the model 81, weighs 200g.
Applications: Typical applications include tail lifts, transmissions on agricultural machinery and differential locks. Prices are "Under £50 net." The model 80 can be supplied with manual override for local operation of for remote operation via a cable. The design is protected by two patents. TS
Sterling Hydraulics