The octagonal pad is a solid metal gasket made of metal material by casting and heat treatment and mechanical processing into a octagonal shape. It has a radial self-tightening effect and is a kind of R type metal ring pad. The principle of effect is It is the contact between the gasket and the inner and outer surfaces (mainly the outer side surface) of the flanged trap groove, and is pressed to form a sealing effect.

Material: carbon steel, stainless steel 304, 316, etc.

Metal octagonal pad

Shape: octagonal, oval

Scope of application: Temperature: -200-800 ° C Pressure: 2.0-42 MPa

Suitable for: high temperature, high pressure pipe flange sealing.

The octagonal metal ring pad is installed in the ladder ring groove of the flange surface. When the connecting bolt is tightened, it is axially tightened and tightened with the upper and lower ladder grooves to form plastic deformation, forming an annular sealing band and establishing an initial seal. After boosting, the ring pad is radially expanded under the effect of the medium pressure. The shims of the gasket and the trapezoidal groove are more tight, resulting in a self-tightening effect. However, the same increase in the pressure of the medium causes the flange and the connecting bolt to be deformed, resulting in a relative separation between the sealing faces, and the gasket sealing ratio is relatively lowered. Therefore, the ring pad can be considered as a semi-self-tightening seal.

The octagonal metal ring pad is mainly in surface contact with the flange groove. Although it is not easy to be in close contact with the flange groove compared with the elliptical ring pad, it can be used again, and the cross section is simply processed by a straight line. The hardness of the octagonal metal ring pad should be lower than the flange surface 15~20HB.

Octagonal metal ring pad features:

1. High temperature resistance and high pressure resistance, suitable for high pressure flanges;

2, the seal is durable and reliable;

3, the habit of pressure, temperature has shaken working conditions;

Octagonal metal ring pad application range: generally used in high temperature and high pressure steam, gas, solvent pipe flange, tower tank, pressure vessel, high speed joint surface, high temperature and high pressure valve, cover. The wellhead equipment in the oil and gas industry and the sealing metal ring mat on the tree are from the United States. They were used in the boiler field in the 1920s and later used for manhole cover, sealing of other windows of the autoclave, and future oil production and refining. Industry is particularly valued. As the temperature and pressure of steam powered equipment increases, the use of metal ring mats is becoming more widespread.