Several Tips for Choosing Gasket of Valves

The purpose of using gasket is that the gasket material can cause elastic deformation easily under compression load which can fill up unsmooth surface of flange sealing face to realize sealing. When connection face suffers from pressure of media, the sealing face is forced to separate. Then, the gasket is required to release enough elastic deformation energy to compensate fractional dose and keep enough working stress of gasket to maintain sealing. 

 

Tips for choosing gasket of valves

1. When choose gasket, sealing performance, working pressure, operating temperature, characteristics of media, types of sealing face, structure, economical efficiency should be considered roundly. Among that, characteristics of media, working pressure and operating temperature are the main factors influencing sealing and also the main bases for choosing gasket.

2. Types of gasket: In general, types of gasket are based on temperature and pressure of media. Metal gasket is used under high temperature and high pressure; non-metal gasket is selected under normal pressure, low pressure and medium temperature; for floating temperature and pressure, self-sealing gasket is chosen.

3. Requirements for gasket materials: The gasket contact with media directly, impacted directly by media, pressure or temperature. Nevertheless, materials used for gasket should meet following requirements:

a. Materials should have good elasticity and appropriate ductility which can coincide to sealing face;

b. The materials cannot pollute media or corrode sealing face. The materials should also have corrosion resistance;

c. The materials should have good physical properties. The materials cannot be hardened or embrittled due to low temperature or melted for high temperature. The materials also should have high cracking resistance or low compressive deformation;

d. The materials should have good machinability. Besides special purpose, gasket also should have low price and can be bought easily from market.