Introduction and Classification of Valve Packing

Packing plays a crucial role in ensuring the proper functioning of valves by preventing leakage of fluid or gas along the valve stem. It's a sealing material used to create a barrier between the moving parts of a valve, such as the stem and the bonnet, to maintain pressure and prevent leaks.

Followings are some frequently used packing:

1.Expanded graphite packing is also known as flexible graphite packing. Expanded graphite packing has advantages such as good self-lubrication and thermal conductivity, low friction coefficient, strong versatility, good flexibility, high strength, and protective effect on the stem. It is a universal packing and widely used in various industries.

2.Reinforced graphite packing is braided from pure expanded graphite wire reinforced with materials such as glass fiber, copper wire, stainless steel wire, and nickel wire. It not only has the various characteristics of expanded graphite, but also has strong versatility, good flexibility, and high strength. Combined with ordinary braided packing, it is the most effective sealing element to solve the problems of high temperature and high pressure sealing.

3.PTFE is known for its excellent chemical resistance and low friction properties. PTFE packing is used in applications involving corrosive fluids and gases.

4.PTFE/Graphite Blends: These blends combine the properties of PTFE and graphite, offering good chemical resistance and stability at high temperatures.

5.Aramid (Kevlar): This packing material is durable, strong, and resistant to abrasion. The most outstanding performance is high strength, good chemical resistance. Aramid packing is often used in applications with abrasive media or high-pressure conditions.

6.Carbon Fiber: It has excellent thermal conductivity, wear resistance, and chemical stability. Carbon fiber packing is designed for high-temperature and high-pressure applications where resistance to abrasion and chemicals is required.

7.Fiberglass: Fiberglass packing is used in applications where resistance to high temperatures and excellent thermal insulation properties are needed.