油压泵简介--中英文翻译详解.doc

本科生毕业设计 (论文) 外 文 翻 译 原 文 标 题 Oil pressure pump cover 译 文 标 题 油压泵简介 作者所在系作者所在专业完 成 时 间 2014 年 月 译文标题 油压泵 原文标题 Oil pressure pump cover 作 者 译 名 国 籍 原文出处 原文 A hydraulic pump is a mechanical device which converts mechanical energy into hydraulic energy.More specifically ,a pump converts the kinetic(moving) energy of a rotating shaft into the kinetic energy of fluid flow. The fluid flow also has potential energy that allows it to overcome the resistance of the system to fluid flow .Remember that a pump provides the force produce flow and transmit power . Hydraulic pressure is caused by the load on the system and by the resistance of the hydraulic system to fluid flow. When operating , a hydraulic pump performs two functions. First, it creates a partial vacuum at its inlet ,permitting the atmospheric pressure in the fluid reservoir to push the hydraulic fluid through the inlet strainer and line into the pump .Second, its mechanical action delivers the fluid to its outlet and into the hydraulic systems, as shown in Fig.5-1. As the fluid leaves the pump, it encounters the working pressure in the system. This pressure is produced by the pressure regulating valve, the system work load ,and flow losses in the hydraulic tubing A pump is classified on the basis of the physical arrangement of its pumping mechanism and its basic principle of operating. Pumps classified by principle of operation include positive displacement and nonpositive-displacement types. Positive-displacement pumps are equipped with a mechanical separation(gears,vanes,or impellers) between the inlet and outlet, which minimizes internal leakage or slippage. Therefore,the output of positive-displacement pumps is almost unaffected by variations in system pressure Nopositive-displacement pumps(such as centrifugal pumps) do not have a positive internal separation against leakage or slippage. Because of this slippage,the delivery of these pump is reduced as the working pres