山东沈北数控机床有限公司欢迎您!  客服热线:13280489678
液压机液压系统泄漏的原因,控制液压系统泄漏的控制办法

液压机液压系统泄漏的原因,控制液压系统泄漏的控制办法

作者:admin    来源:未知    发布时间:2020-08-26 18:53    浏览量:

一、液压机液压系统泄漏的原因

(1)设计及制造的缺陷所造成的;

(2)冲击和振动造成管接头松动;

(3)动密封件及配合件相互磨损(液压缸尤甚);

(4)油温过高及橡胶密封与液压油不相容而变质。下面就结合以上几个方面浅谈一下控制泄漏的措施。

 

二、控制液压机液压系统泄漏的控制办法

 

办法一:设计及制造缺陷的解决方法

1、液压元件外配套的选择往往在液压机液压系统的泄漏中起着决定性的影响。这就决定我们技术人员在新产品设计、老产品的改进中,对缸、泵、阀件,密封件,液压辅件等的选择,要本着好中选优,优中选廉的原则慎重的、有比较的进行。

2、合理设计安装面和密封面:当阀组或管路固定在安装面上时,为了得到满意的初始密封和防止密封件被挤出沟槽和被磨损,安装面要平直,密封面要求精加工,表面粗糙度要达到0.8μm,平面度要达到0.01/100mm。表面不能有径向划痕,连接螺钉的预紧力要足够大,以防止表面分离。

3、在制造及运输过程中,要防止关键表面磕碰,划伤。同时对装配调试过程要严格的进行监控,保证装配质量。

4、对一些液压机液压系统的泄露隐患不要掉已轻心,必须加以排除。

 

办法二:减少冲击和振动

为了减少承受冲击和振动的管接头松动引起的液压机液压系统的泄漏,可以采取以下措施:

①使用减震支架固定所有管子以便吸收冲击和振动;

②使用低冲击阀或蓄能器来减少冲击;

③适当布置压力控制阀来保护系统的所有元件;

④尽量减少管接头的使用数量,管接头尽量用焊接连接;

⑤使用直螺纹接头,三通接头和弯头代替锥管螺纹接头;

⑥尽量用回油块代替各个配管;

⑦针对使用的最高压力,规定安装时使用螺栓的扭矩和堵头扭矩,防止结合面和密封件被蚕食;

⑧正确安装管接头。

 

办法三:减少液压机液压系统动密封件的磨损

大多数动液压机液压系统密封件都经过精确设计,如果动密封件加工合格,安装正确,使用合理,均可保证长时间相对无泄漏工作。从设计角度来讲,设计者可以采用以下措施来延长动密封件的寿命:

1、消除活塞杆和驱动轴密封件上的侧载荷;

2、用防尘圈、防护罩和橡胶套保护活塞杆,防止磨料、粉尘等杂质进入;

3、设计选取合适的过滤装置和便于清洗的油箱以防止粉尘在油液中累积;

4、使活塞杆和轴的速度尽可能低。

 

办法四:对静密封件的要求

静密封件在刚性固定表面之间防止油液外泄。合理设计液压机液压系统密封槽尺寸及公差,使安装后的密封件到一定挤压产生变形以便填塞配合表面的微观凹陷,并把密封件内应力提高到高于被密封的压力。当零件刚度或螺栓预紧力不够大时,配合表面将在油液压力作用下分离,造成间隙或加大由于密封表面不够平而可能从开始就存在的间隙。随着配合表面的运动,静密封就成了动密封。粗糙的配合表面将磨损密封件,变动的间隙将蚕食密封件边缘。

 

方案五:控制油温防止密封件变质

液压机密封件过早变质可能是由多种因素引起的,一个重要因素是油温过高。温度每升高10℃则密封件寿命就会减半,所以应合理设计高效液压系统或设置强制冷却装置,使最佳油液温度保持在65℃以下;工程机械不许超过80℃;另一个因素可能是使用的油液与密封材料的相容性问题,应按使用说明书或有关手册选用液压油和密封件的型式和材质,以解决相容性问题,延长密封件的使用寿命。

 

 

1、 Causes of leakage in hydraulic system of hydraulic press

(1) Caused by design and manufacturing defects;

(2) The pipe joint is loose due to impact and vibration;

(3) Dynamic seals and mating parts wear each other (especially hydraulic cylinder);

(4) The oil temperature is too high and the rubber seal is incompatible with the hydraulic oil. The following is the combination of the above several aspects on the control of leakage measures.

2、 Control method of hydraulic system leakage control of hydraulic press

Solution 1: solutions to design and manufacturing defects

1. The selection of external matching of hydraulic components often plays a decisive role in the leakage of hydraulic system of hydraulic press. This determines that in the design of new products and the improvement of old products, the selection of cylinders, pumps, valves, seals, hydraulic accessories, etc. should be based on the principle of selecting the best from the good and selecting the low from the excellent carefully and comparatively.

2. Reasonable design of the installation surface and sealing surface: when the valve group or pipeline is fixed on the installation surface, in order to obtain a satisfactory initial seal and prevent the seal from being squeezed out of the groove and being worn, the installation surface shall be straight, the sealing surface shall be finished, the surface roughness shall be 0.8 μ m, and the flatness shall be 0.01/100 mm. There should be no radial scratches on the surface, and the pre tightening force of the connecting screw should be large enough to prevent surface separation.

3. In the process of manufacturing and transportation, the key surface should be prevented from bumping and scratching. At the same time, the assembly and debugging process should be strictly monitored to ensure the assembly quality.

4. The hidden danger of leakage of some hydraulic press hydraulic system must be eliminated.

Method 2: reduce impact and vibration

In order to reduce the leakage of the hydraulic system of hydraulic press caused by the loosening of pipe joints under impact and vibration, the following measures can be taken:

① All pipes shall be fixed with damping supports to absorb shock and vibration;

② Use low impact valve or accumulator to reduce impact;

③ Proper arrangement of pressure control valves to protect all components of the system;

④ The number of pipe joints shall be reduced as far as possible, and the pipe joints shall be welded as far as possible;

⑤ Use straight thread joint, tee joint and elbow instead of taper pipe thread joint;

⑥ Try to use oil return block instead of each piping;

⑦ According to the maximum pressure used, the torque of bolt and plug should be specified to prevent the joint surface and seal from being eroded;

⑧ Install the coupling correctly.

Three ways to reduce hydraulic seal wear

Most of the seals of the hydraulic system of the dynamic hydraulic press are designed accurately. If the seals are processed properly, installed correctly and used reasonably, they can ensure that there is no leakage for a long time. From the design point of view, designers can adopt the following measures to extend the life of dynamic seals:

1. Eliminate side load on piston rod and drive shaft seal;

2. Protect piston rod with dust ring, protective cover and rubber sleeve to prevent impurities such as abrasives and dust from entering;

3. In order to prevent the dust from accumulating in the oil, proper filter device and easy to clean oil tank are designed and selected;

4. Keep the rod and shaft speed as low as possible.

Method 4: requirements for static seals

Static seals prevent oil leakage between rigid fixed surfaces. The size and tolerance of sealing groove in hydraulic system of hydraulic press should be designed reasonably, so that the installed seal will deform to a certain extent, so as to fill the micro depression on the mating surface, and increase the internal stress of the seal to higher than the sealed pressure. When the part stiffness or bolt pre tightening force is not large enough, the mating surface will separate under the action of oil pressure, resulting in the gap or increasing the gap that may exist from the beginning due to the uneven sealing surface. With the movement of the mating surface, the static seal becomes the dynamic seal. The rough mating surface will wear the seal and the variable clearance will nibble at the seal edge.

Scheme 5: control oil temperature to prevent seal deterioration

Premature deterioration of hydraulic seal may be caused by many factors, one of which is high oil temperature. If the temperature increases by 10 ℃, the service life of the seal will be reduced by half. Therefore, it is necessary to reasonably design an efficient hydraulic system or set up a forced cooling device to keep the optimal oil temperature below 65 ℃; the construction machinery shall not exceed 80 ℃; another factor may be the compatibility between the oil used and the sealing material. The type and type of the hydraulic oil and seal shall be selected according to the operation manual or relevant manual Material to solve the compatibility problem and prolong the service life of the seal.

相关新闻推荐

在线客服 :

服务热线:13280489678

电子邮箱: 675609587@qq.com

公司地址:山东省枣庄市滕州市经济开发区

Copyright © 2002-2020 山东沈北数控机床有限公司 版权所有--备案号:鲁ICP备20014639号-2