कंपनी की खबर रोल बनाने की मशीन तेल सिलेंडर

In engineering hydraulic oil cylinder work in the, sometimes implementation components in short time stop work, not need engineering hydraulic oil cylinder passed energy, or implementation components in a paragraph work time within keep must of force, and movement speed very slow, even stop movement, in this situation Xia, not need hydraulic pump output oil liquid, or only need is small flow of hydraulic oil, so hydraulic pump output of pressure oil all or most from spill flow valve flow back tank, caused energy loss serious. To this end, the relief circuit is needed, unloading of hydraulic pump hydraulic pump drive motor without frequent opening and closing of the case, the hydraulic pump to power output near-zero operation. Unloading of hydraulic pump has a flow of unloading and pressure unloading two, the former is the use of variable displacement pump, variable displacement pump to operate at minimum flow only to compensate for leakage, this method is relatively simple, but the pump is still operating at high pressure, more serious wear; pressure unloading is to make the pump run at close to zero pressure.