Working principle: piston moves from left to right, form a negative pressure pump cylinder, the liquid tank into the pump by the inhalation valve cylinder.

工作原理：活塞自左向右移动时，泵缸内形成负压，则贮槽内液体经吸入阀进入泵缸内。

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What is a hydraulic press?The hydraulic press is by the high-pressured liquid (oil, emulsion and so on) transmits the working pressure the forging and stamping machinery.

什么是液压机?液压机是以高压液体（油、乳化液等）传送工作压力的锻压机械。

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Liquid system is the need for oil pressure, flow, direction control and regulation to meet the needs of working parts in the power, speed and direction requirements.

液正系统工作，必须对油液压力、流量、方向进行控制与调节，以满足工作部件在力、速度和方向上的要求。

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