1) the following factors should be taken into consideration when selecting the manhole flange gasket.
A. for sealing highly toxic chemicals, the gasket should be more secure. For piping systems conveying flammable liquids, gaskets are required for maximum pressure and maximum service temperature on flanges.
B. has good plasticity and can fit well with the manhole flange seal face.
C. has good processing performance, easy to install and press tight.
D. does not stick manhole flange close cover, easy to disassemble.
E. for some metal (such as austenitic stainless acid resistant steel) manhole flanges with stress corrosion cracking, we should ensure that the gasket materials do not contain excessive impurities which will cause various corrosion, such as controlling the chloride content of the gaskets to prevent flange corrosion.
F. has good compression and rebound performance, and can adapt to the fluctuation of temperature and pressure.
G. does not pollute the medium (the sealing medium is drinking water, plasma, medicine, food, beer and so on).
H. is not easy to harden at low temperature, small
shrinkage, not easy to soften at high temperature, and good resistance to creep.
2) if you choose or order a gasket, you should know the data.
A. matching manhole flange seal face type and size;
B. flange and gasket nominal diameter;
C. flange and gasket nominal pressure;
The temperature of the D. retention medium;
The properties of the E. retention medium.