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Analysis of Sealing Method of Hydraulic Cylinder

Hydraulic cylinder is a hydraulic machine implementing component that converts hydraulic function into mechanical kinetic energy and performs repeated parallel motions. It is simple in construction and reliable in operation. When using it to complete repeated movements, it can eliminate the need for deceleration equipment, and there is no gap in the transmission system, and the fitness movement is stable, so it is widely used in the hydraulic transmission system of various mechanical equipment.

Ⅰ. The composition of the hydraulic cylinder

The hydraulic cylinder is generally composed of key parts such as rear bearing end cover, cylinder liner, hydraulic cylinder, piston rod parts, front-end development cover, etc.; There are sealing devices between the bearing end cover, the piston rod and the hydraulic cylinder, the piston rod and the cylinder liner, the hydraulic cylinder and the front-end development cover. When it is quickly returned to the itinerary terminal equipment, it collides with the cylinder head, and the top of the hydraulic cylinder is also set with a buffer device; sometimes it is necessary to set a steam and water separator.

Ⅱ. The sealing method of the hydraulic cylinder

1. Airtightness

The principle is that there will be a little gap between the two fitness moving parts, and the liquid friction caused in the gap will avoid leakage. This method has certain disadvantages, that is, it is only suitable for the sealing between the hydraulic cylinder and the piston rod with small diameter and working pressure. The advantage is that in order to better improve the high efficiency of this type of sealing, several concave grooves will be given on the piston rod, this concave groove will allow the hydraulic oil to change the path or disconnect in the case of internal leakage, and generate vortices in the small groove body to cause frictional resistance, thus reducing the leakage of hydraulic oil; another The aspect is to block the deviation of the center line of the piston rod, which is beneficial to maintain the mutual matching gap, ensure the actual effect of lubrication, reduce the wear of the piston rod and the cylinder wall, and improve the sealing performance of the gap.

2. The effect of choosing silicone sealing ring

Because the types of sealing rings in the hydraulic cylinder are different, the sealing principles selected are also different. Among them, the O-ring is mainly used for pre-reduction to offset the gap to complete the sealing effect.

3. Use sealing gasket parts to complete the sealing effect

This kind of sealing is generally composed of two types of hydraulic seals, and they can fully exert their sealing effect at the same time. The excellent ductility of the O-type silicone ring in work results in predictable self-lubrication, which makes it longer in the application of hydraulic cylinder sealing.