CLASSIFICATION AND APPLICATION OF SEALING RING

Construction machinery is inseparable from the oil cylinder, and the oil cylinder is inseparable from the seal. The common seal is the sealing ring, which plays the role of isolation and prevents the medium from overflowing or passing through. Sealing ring is widely used in non contacting mechanical seal, gland packing, pump seal, spring seal, elastomer bellows seal, etc. The following describes the types of common sealing rings and their applications.

V-ring

V-ring is a kind of elastic rubber sealing ring with axial action, which is used as non pressure seal of rotating shaft. Its sealing lip has good mobility and adaptability, can compensate for large tolerance and angle deviation, can prevent internal grease or oil from leaking out, and can also prevent the invasion of external water or dust.

U-ring

This kind of sealing ring is often used to make reciprocating seal in hydraulic system and also widely used in the seal of hydraulic cylinder in construction machinery.

O-ring

This kind of sealing ring is mainly used for static seal, reciprocating seal and low-speed rotary seal.

Dust Ring

The dust ring is mainly installed on the outside of the end cover of the hydraulic cylinder to prevent external pollutants from entering the cylinder. According to the installation method, it can be divided into snap-in type and press-in type. Snap-in dust ring is the most common. It can be directly clipped into the groove of the inner wall of the end cover, which is used in ordinary working conditions. The material of this kind of dust ring is usually polyurethane.

Press-in dust ring is used under severe and heavy load conditions. Polyurethane is the raw material of this kind of dust ring. There is a layer of metal on the outside of polyurethane to increase the strength of the dust ring. According to its structure, the press-in dust ring can be divided into single sealing lip dust ring and double sealing lip dust ring.

Piston Rod Sealing Ring

This kind of sealing ring is the main piston rod seal, which is installed inside the end cover of the hydraulic cylinder to prevent the hydraulic oil from leaking out. The piston rod seal ring is made of polyurethane or nitrile rubber. In some cases, it needs to be used together with the support ring, which is used to prevent the seal ring from deforming under pressure.

Buffer Sealing Ring

This kind of sealing ring is an auxiliary piston rod seal ring used to protect the piston rod when the system pressure suddenly increases.

Guide Support Ring

The guide support ring is installed on the end cover and piston of the hydraulic cylinder to support the piston rod and piston and guide the piston to move in a straight line to prevent metal to metal contact.

End Cover Sealing Ring

The end cover sealing ring is used to seal the end cover and the wall of the oil cylinder. It is a static seal to prevent the hydraulic oil from leaking out from the gap between the end cover and the wall of the oil cylinder. It is usually composed of NBR O-ring and support ring.