What Causes Hydraulic Cylinder Oil Leakage?
2 Answers
The reasons for hydraulic cylinder oil leakage may include severe wear of the wear-resistant ring on the piston, causing friction between the piston and cylinder liner, ultimately damaging the cylinder liner, piston, and seals; failure of seals due to prolonged use, aging of piston seals (U, V, Y-rings, etc.); excessively dirty hydraulic oil, with a large amount of impurities entering the cylinder and wearing out the piston seals; cracking of the oil inlet and outlet pipe joints; damage to the seal at the extension end of the piston rod due to scoring of the piston cylinder or aging; damage to the seal at the extension end of the piston rod and cylinder liner due to prolonged use and aging of the seal, or excessive force when installing the upper end cover causing seal compression damage. The hydraulic cylinder is a hydraulic actuator that converts hydraulic energy into mechanical energy, performing linear reciprocating motion (or swinging motion). It has a simple structure and reliable operation. When used to achieve reciprocating motion, it can eliminate the need for a reduction device and has no transmission gap, ensuring smooth movement. The output force of the hydraulic cylinder is proportional to the effective area of the piston and the pressure difference on both sides. The hydraulic cylinder is basically composed of a cylinder barrel and cylinder head, piston and piston rod, sealing device, buffer device, and exhaust device. There are various structural forms of hydraulic cylinders, and their classification methods are also diverse: according to the motion mode, they can be divided into linear reciprocating and rotary swinging types; according to the hydraulic pressure action, they can be divided into single-acting and double-acting types; according to the structural form, they can be divided into piston, plunger, multi-stage telescopic sleeve, rack and pinion, etc.; according to the installation form, they can be divided into tie rod, clevis, foot, hinge pin, etc.; according to the pressure level, they can be divided into 16Mpa, 25Mpa, 31.5Mpa, etc. Treatment methods: Hydraulic oil under high pressure repeatedly moves and exerts a certain impact force on the sealing performance. Therefore, after a certain period of use, it should be moderately replaced to achieve optimal sealing performance. Maintain heat dissipation and natural ventilation to preserve the efficiency of the hydraulic transmission system.
As a seasoned mechanic with twenty years of experience, I've encountered numerous cases of hydraulic cylinder oil leakage. The most common issue is aging seals, especially O-rings and sealing rings, which naturally wear out over time and lose their elasticity, leading to leaks. If the cylinder body or piston rod is scratched or cracked, high oil pressure can easily cause seepage from the damaged points, particularly after prolonged use on rough roads where components are prone to deformation. Improper installation is another frequent cause, such as loose screws or misaligned angles, resulting in poor sealing. Additionally, poor-quality oil can corrode sealing materials, exacerbating leaks. I recommend regular inspections of the hydraulic system and prompt replacement of seals at the first sign of minor oil stains to avoid complete cylinder failure and costly major repairs.
