溢流阀

目录

摘要 (3)

一绪论 (5)

1.1液压技术的发展历史 (5)

1.2我国液压阀技术的发展概况 (5)

1.3本课题的目的及研究范围 (7)

二溢流阀设计主体

2.1简单溢流阀的工作原理 (7)

2.2溢流阀的结构设计 (8)

2.3直动型溢流阀 (8)

2.4先导式溢流阀 (10)

三溢流阀主要参数设计 (11)

3.1静态特性 (12)

3.2动态特性 (13)

3.3先导型溢流阀的静态特性分析 (15)

四溢流阀的基本应用............................ 错误！未定义书签。五溢流阀主要零件的加工 19 六溢流阀常见故障原因分析及排除方法 (24)

6.1噪声和振动 (24)

6.2阀芯径向卡紧............................... 错误！未定义书签。

6.3调压失灵................................... 错误！未定义书签。

6.4其它故障................................... 错误！未定义书签。

总结 (23)

致谢 (26)

参考文献........................................ 错误！未定义书签。

摘要

液压传动是利用密闭系统中受压液体来传递运动和动力的一种传递方式。

其介质为油压液体，包括液压油和其他合成液体，其特点为动力大，运动平稳。但由于液压粘度大，在流动过程中阻力损失大，因而不宜做远距离传动和控制。

在液压传动系统中，液流的压力是最基本的参数之一，执行元件的输出力或输出扭矩的大小，主要由供给的液压力所决定。为了对油液压力进行控制，并实现和提高系统的稳压、保压、减压、调压等性能或利用压力变化实现执行机构的顺序动作等，根据油液压力和控制机构弹簧力相平衡的工作原理，人们设计制造了各种压力控制阀。在液压设备中主要起定压溢流作用和安全保护作用。

定压溢流作用：在定量泵节流调节系统中，定量泵提供的是恒定流量。当系统压力增大时，会使流量需求减小。此时溢流阀开启，使多余流量溢回油箱，保证溢流阀进口压力，即泵出口压力恒定（阀口常随压力波动开启）。

安全保护作用：系统正常工作时，阀门关闭。只有负载超过规定的极限（系统压力超过调定压力）时开启溢流，进行过载保护，使系统压力不再增加（通常使溢流阀的调定压力比系统最高工作压力高10％～20％）。

实际应用中一般有：作卸荷阀用，作远程调压阀，作高低压多级控制阀，作顺序阀，用于产生背压（串在回油路上）。

溢流阀一般有两种结构：1、直动型溢流阀 2、先导型溢流阀

关键词：工作原理、实际应用、设计加工

A bstract

Hydraulic transmission is airtight system using liquid pressure to deliver the power of the movement and a transfer mode.

The medium for hydraulic liquid, including the hydraulic oil and other sy nthetic liquid, its characteristic is power, smooth movement. But because the hydraulic viscosity, flow in process resistance losses, and not suitable for long-distance transmission and control.

In hydraulic transmission system, the liquid flow pressure is one of the most basic parameters, the implementation of components of the output force or the size of the output torque, mainly from supplies to the hydraulic pressure. In order to control oil pressure, and realize and improving system on voltage stability, the pressure, and the reduced pressure, pressure regulating, such as performance or by using pressure change of the actuator realize order action, according to the oil pressure and control agencies balance spring force of the working principle, design and manufacture all kinds of people pressure control valves. In hydraulic equipment mainly up in the constant pressure relief effect and safety protection.

The constant pressure relief action: in quantitative pump throttling control system, the quantitative pump is a constant flow of the offer. When the system pressure increases, can make the flow demand decrease. At this time the overflow valve opens, overflow excessive flow back to fuel tank, and ensure the inlet pressure relief valve, namely pump outlet p ressure constant (valve with mouth often pressure fluctuations open). Safety protection: the normal work of the system, the valve closed. Only load exceed the limit (the system pressure is more than the set pressure) open when overflow, overload protection, no longer increases the system pressure (usually make the adjustment for pressure relief valve than the highest high pressure system work 10% ~ 20%). The practical application in general have: be unloading with valve, pressure regulating valves remote, high and low voltage multilevel control valves, as order valve, used to produce back pressure (in the back of the oil). Relief valve is usually two kinds of structure: 1, straight moving type relief valve 2, the guiding relief valve