The Main Parts and Causes of Leakage of EPS Equipment Hydraulic System


1. Pipe Joints and Oil Plugs


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Most of the pipe joint oil leakage occurs on the connection parts of the manifold block, valve 

base plate, pipe element, etc. with the pipe joint. When the pipe joint is connected with the 

metric thread, it will cause the seal of the combined gasket to leak tightly. The plugs cannot 

be completely matched with each other and are prone to oil leakage. Once the above two 

situations occur, it is difficult to cure, and can only be filled and sealed with the help of liquid 

sealant or PTFE raw material tape.

2. Oil Leakage Between Joint Surfaces Such as Plate Valves and Superimposed Valves

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If it collides with the mounting surface of the O-ring, scratches it, the mounting screws are 

long, and the strength is not enough, oil leakage will occur. Deal with the above issues 

separately when solving.

3. Reasons for Oil Leakage from Hydraulic Cylinders

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Dust, mud, salt spray, surface scratches, and eccentric load on the piston rod surface will 

cause seal damage and oil leakage due to failure. The solution is to try not to subject the 

hydraulic cylinder to eccentric load, and often wipe the dust on the piston rod, pay 

attention to avoid bumps and scratches, and do a good job of hydraulic oil cleanliness 


4. The Temperature is Too High

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The temperature rise and heat cause serious leakage, which can reduce or deteriorate the 

viscosity of the oil and increase the internal leakage. If the temperature continues to 

increase, it will cause the sealing material to expand after heating and increase friction, 

which will accelerate wear, axial rotation or sliding. Leakage quickly occurred. The O-ring 

expands and deforms and causes thermal aging. After cooling, it cannot return to its original 

state, loses elasticity and fails, and gradually leaks.

TIPS:periodic inspection, regular maintenance, and timely processing are the most basic guarantees to prevent leakage and reduce failures.

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