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Hydraulic seals for hydraulic cylinders and pneumatic cylinders are mutually dependent seals within mechanical systems. Frequent failures in the operation of hydraulic cylinders in hydraulic systems are due to wear on the inner wall surface of the cylinder, gradually forming scratches, and secondly, irregular wear.

After the sealing ring wears, the larger the gap between the opening and the surrounding area, the smaller the elasticity of the hydraulic cylinder pneumatic cylinder seal, and the lower the sealing performance. Piston seal wear is mainly due to the unreasonable coordination between the mechanical movement process and the piston seal ring, at which time axial grooves are likely to appear.

Because the small and large cylinders are interconnected and continuously filled with liquid on average, the liquid pressure in the small cylinder will be transmitted to all points in the liquid, and of course, to the point where the large cylinder contacts the piston. (This is the principle of pressure transmission in static liquids, known as Pascal's principle.)

The effective area of the piston in the small cylinder is small, while the effective area of the piston in the large cylinder is large. By applying a small force to the piston, the piston can lift heavy objects.

If the hydraulic cylinder seal is not severely worn and there are no grooves, the piston and piston rings can be replaced. Generally, if the piston ring opening gap exceeds 0.5mm and the edge gap exceeds 0.12mm, a new cylinder seal must be replaced to maintain the standard gap balance. If the piston seal and hydraulic cylinder pneumatic cylinder seal are excessively worn, the mating gap exceeds 0.15mm, or there are serious scratches on the sealing surface, repairs can be carried out according to the repair method for engine cylinder pistons. That is, a new piston and piston ring with increased dimensions are fitted behind the money pot to restore the matching requirements. If the piston is not frayed on the hydraulic cylinder, the piston ring groove can be enlarged and switched to an O-ring. After the hydraulic cylinder cylinder and piston are repaired, the following technical requirements are met: the standard spacing of the cylinder seal and piston seal maintains the same cylinder seal diameter; the standard opening spacing of the piston ring is 0.05mm, the surface finish should remain smooth, and the elasticity of the sealing strip should be noted. During light leakage inspection, the length of light transmission cannot exceed the circumference.

Advantages of Hydraulic Cylinders 1

Pneumatic systems typically use pressures in the range of 0.2-1.0 MPa, so cylinders cannot be used to create high-power actuators. Hydraulic cylinders can be used to create high-power components using hydraulic systems.

Advantages 2

In the media, air is unlimited, there are no cost or supply difficulties, and the used gas is directly discharged into the atmosphere, making disposal convenient, non-polluting, unlike hydraulic oil.

Advantages 3

Air has low viscosity and lower resistance than hydraulic oil.

Advantages 4

However, air has a much higher compressibility than hydraulic oil, so its operational stability and responsiveness are poor. Hydraulic cylinders are important actuators in hydraulic systems. They convert hydraulic energy into mechanical energy and cooperate with various transmission mechanisms to complete various mechanical movements.