The ring joint gasket is a solid metal gasket with an oval cross-sectional shape made of metal materials by forging, heat treatment and machining. It has a radial self-tightening sealing effect and is a standard R-type metal ring gasket. Its function principle is It depends on the contact between the gasket and the inner and outer surfaces (mainly the outer side) of the flange trapezoidal groove, and forms a sealing effect by pressing.
The oval metal ring joint gasket is installed in the trapezoidal ring groove on the flange surface. When the connecting bolt is tightened, it is axially compressed and tightly attached to the upper and lower trapezoidal grooves, resulting in plastic deformation, forming an annular sealing band and establishing the initial seal. After boosting, under the action of medium pressure, the ring gasket is radially expanded. The gasket and the inclined surface of the trapezoidal groove are more tightly fitted, resulting in a self-tightening effect. However, the increase of the medium pressure will also deform the flange and the connecting bolt, resulting in the relative separation between the sealing surfaces and the relative decrease in the gasket sealing ratio. Therefore, the ring gasket can be considered as a semi-self-tightening seal.
The oval ring gasket and the flange groove are in line contact, and the sealing performance is good, but the processing accuracy is high, so the manufacturing cost is high. At the same time, the hardness of the oval metal ring gasket should be 15~20HB lower than the flange surface, and it is recommended not to use it. reuse.
Oval metal ring gasket performance characteristics:
1. High temperature resistance and high pressure resistance, suitable for high pressure flanges;
2. The seal is durable and reliable;
3. Adapt to working conditions with fluctuations in pressure and temperature;
Scope of application:
Usually 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. Wellheads and seals on Christmas trees in the oil and gas industry
Metal ring gaskets originated from the United States and were first used in the boiler field in the 1920s. Later, they were used for manhole covers and the sealing of other windows in autoclaves. Later, they received special attention in the oil production and refining industries. As the temperature and pressure of steam power plants increased, the use of metal ring gaskets became more and more widespread.
评论
发表评论