O-ring sealing principle

The sealing ring should generally have good physical and mechanical properties, high resilience, small compression set, reliable sealing, convenient processing and long service life. Silicone rubber sealing ring can withstand high temperature and low temperature, radiation resistance, vacuum resistance, non-polluting, non-toxic; polysulfide rubber sealant has excellent resistance to aviation fuel, as well as high temperature resistance, high pressure resistance, friction resistance, pressure resistance, these It is the leading direction of the sealing industry. The quality of the sealing ring directly affects the production efficiency of the mechanical equipment. If you buy inappropriate products, it will have a great impact on the efficiency of the equipment.

Sealing principle: O-ring seal is an extrusion type seal. When the seal has initial deformation and stress Pseal, Pw>Pseal, there will be no leakage.

Pmu003dP0+Pp, Ppu003dK×P.

Pmu003dP0+K×P

K is the coefficient of medium pressure transfer to O-ring pressure (for rubber, Ku003d1)

Therefore, as long as the initial pressure of the O-ring exists, a leak-free absolute seal can be achieved. The O-ring seal is a self-sealing structure.

Internal pressure: the outer diameter of the O-ring is the same as the outer diameter of the groove

External pressure: the inner diameter of the O-ring is the same as the inner diameter of the groove

Prevents O-ring diameter reduction under working pressure.

O-rings are subject to tension or compression when installed in the groove. Excessive values u200bu200bof tension and compression will result in an excessive increase or decrease in the cross-section of the O-ring, since 1% stretching correspondingly reduces the cross-sectional diameter W by about 0.5%. For hole (internal pressure) seals, the O-ring is preferably in a stretched state, with a maximum allowable stretch of 6%; for shaft (internal pressure) seals, the O-ring is preferably compressed along its circumference. The maximum allowable perimeter compression is 3%.

The selection of sealing ring material should first consider its bonding properties and use parts. The good bonding between the sealing material and the substrate to be adhered is a necessary condition to ensure the sealing. Therefore, a sealing material with good adhesion should be selected according to the material, surface state and properties of the substrate to be adhered. For the joints in different parts of the building, the requirements for the sealing materials are also different. For example, the outdoor joints require higher weather resistance, while the expansion joints require better elastic-plastic and tensile-compression cycle performance. Delong Xingye has rich experience in chemical corrosion resistance, wear resistance, high and low temperature resistance, and can provide advanced sealing solutions for all walks of life.