Know the common knowledge of U-shaped seals

U-shaped sealing ring is a type of reciprocating seal, the section is U-shaped, referred to as U-shaped sealing ring. There are two types of U-shaped seals, rubber type and cloth type. The U-shaped seal made of PTFE as the base material and then adding filler can be installed on the moving piston, and can also be installed on the casing as a fixed seal to play a sealing role without adjusting the packing gland.

U-shaped seal advantages: single lip form has: no effect on heavy load and piston rod bending, compared with double lip form, lower friction in the low pressure range Double lip form has: good corrosion resistance and wear resistance good performance, a good lubricating oil film is formed in the sealing gap, and it has no effect on sudden load.

U-shaped seals are balanced seals, that is, seals on both the inner and outer diameters, and are equipped with a backup ring to protect the seal from being squashed or twisted under pressure. The U-shaped ring is installed in the sealing groove, and the gap between the pressure ring and the lip is 1.6 ~ 3mm, that is, at least 25% of the thickness of the lip, so that the lip should not touch the pressure ring, so that the system fluid can enter freely, so that the principle of self-tightening can be used. Seal. The transverse holes in the vertical web of the pressure ring ensure the pressure balance in the U-shaped opening. A rubber O-ring is used to increase static and dynamic contact forces to improve initial sealing.u200bu200b