How to control hydraulic system leakage?

The hydraulic system we often say is both a hydraulic drive system and he increases the force by changing the pressure. Some netizens asked how to effectively control the leakage of the hydraulic system. The methods for reviewing relevant information are as follows.

Design and manufacturing defect solutions

l. The choice of external components of hydraulic components often plays a decisive role in the leakage of hydraulic systems. This determines our technicians in the design of new products, the improvement of old products, the choice of cylinders, pumps, valve parts, seals, hydraulic accessories, etc., must be based on the principle of good selection, excellent selection of low-cost, prudent, There is a comparison.

2. Reasonable design of the mounting surface and sealing surface: When the valve block or pipeline is fixed on the mounting surface, in order to obtain a satisfactory initial seal and prevent the seal from being squeezed out of the groove and worn, the mounting surface should be straight and the sealing surface Finishing is required, the surface roughness should be 0.8Î¼m, and the flatness should be 0.01/100mm. The surface must not have radial scratches and the pre-tightening force of the connecting screws should be large enough to prevent surface separation.

3. During the manufacturing and transportation process, it is necessary to prevent key surfaces from bumping and scratching. At the same time, the assembly and debugging process must be strictly monitored to ensure the quality of the assembly.

4, for some of the hydraulic system leakage hidden dangers should not be taken lightly, must be excluded.

Control oil temperature to prevent seal deterioration

Premature deterioration of seals can be caused by a variety of factors, an important factor being excessive oil temperature. For every 10 Â°C increase in temperature, the life of the seal will be halved. Therefore, a high-efficiency hydraulic system or a forced cooling device should be designed to keep the optimum oil temperature below 65 Â°C; the construction machinery must not exceed 80 Â°C; another factor It may be the compatibility of the oil and sealing material used. The type and material of the hydraulic oil and seal should be selected according to the instruction manual or related manual to solve the compatibility problem and prolong the service life of the seal.

Reduce shock and vibration

In order to reduce the leakage of the hydraulic system caused by the looseness of the pipe joint subjected to shock and vibration, the following measures can be taken:

1 Use a shock absorbing bracket to secure all the tubes to absorb shock and vibration;

2 use a low impact valve or accumulator to reduce the impact;

3 properly arrange the pressure control valve to protect all components of the system;

4 Try to reduce the number of pipe joints used, and the pipe joints should be welded as much as possible;

5 use straight threaded joints, tees and elbows instead of taper threaded joints;

6 Try to replace each pipe with a return block;

7 For the highest pressure used, the torque and plug torque of the bolts used during installation are specified to prevent the joint surface and the seal from being eaten away;

8 Install the pipe joint correctly.

Requirements for static seals

The static seal prevents oil from escaping between the rigid fixed surfaces. Reasonably design the size and tolerance of the sealing groove so that the installed sealing member is deformed to a certain extrusion to fill the microscopic depression of the mating surface, and the internal stress of the sealing member is raised to be higher than the pressure to be sealed. When the part stiffness or bolt preload is not large enough, the mating surface will separate under the action of oil pressure, causing a gap or increasing the gap that may exist from the beginning due to the flat surface of the seal. As the mating surface moves, the static seal becomes a dynamic seal. A rough mating surface will wear the seal and the varying gap will encroach on the edge of the seal.

Reduce wear on dynamic seals

Most dynamic seals are precisely designed. If the dynamic seals are processed properly, they are properly installed and used reasonably, they can guarantee relatively long leakage-free operation. From a design perspective, the designer can use the following measures to extend the life of the dynamic seal:

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

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

3. Design a suitable filter device and a fuel tank that is easy to clean to prevent dust from accumulating in the oil;