1、 Performance requirements for high-pressure valve packing

(1) The tightly woven medium of sealed packing has permeability to most fibers. The mechanical properties of tightly woven packing are strong, which can effectively prevent the penetration of the medium and damage to the packing.

(2) Strong anti-wear ability, long sealing cycle. The packing should be tightly attached to the valve stem to prevent medium leakage. However, the greater the pressure of the packing on the valve stem, the more severe the wear will be. Therefore, the packing should have very good anti-wear ability. Even if it is applied to valves with high pressure and frequent opening and closing, it will not cause serious wear.

(3) The self-lubricating performance does not affect the wear resistance of the valve's opening and closing gaskets, which can ensure that the gaskets will not cause serious wear when the valve is frequently opened and closed. However, the gaskets still have a huge resistance to the reciprocating motion of the valve stem. Therefore, it is necessary to ensure the lubrication of the gaskets, which can effectively reduce the wear of the gaskets and valve stem.

Material of sealing disc root for two valves

1. Ordinary packing

(1) Natural fiber based roots. Mainly including cotton, linen, and wool, these are the earliest fibers used in the production of roots. This type of root material is low-cost and widely available, but its sealing performance is not ideal. With the advancement of root manufacturing technology, the application scope of this type of root has gradually narrowed.

(2) Mineral fiber packing. Mainly referring to asbestos packing, this type of packing has good sealing effect and is used for valves with weak acid and alkali, liquid ammonia, water, and oil media. It has the best static sealing and anti-corrosion sealing effect. However, due to the fact that asbestos fibers can cause diseases such as asbestosis and pleural mesothelioma, and the production process seriously pollutes the environment, many countries have chosen to completely ban the use of this hazardous substance.

(3) Synthetic fiber packing. This type of packing combines the advantages of many materials, but the unit price is relatively high.

2. Packing suitable for high-pressure valves

(1) Graphite series. Graphite packing is made of graphite as the main material. It has good self-lubricating and thermal conductivity, low friction coefficient, strong universality, good flexibility, high strength, and protective effect on the shaft. It is called "packing". Depending on the application environment, metal wire can be used to strengthen its mechanical strength during weaving to better meet the requirements of high-pressure valves. Suitable for sealing valve stems under high temperature and high pressure conditions.

(2) Carbon fiber series. This series of packing is mainly made of carbon fiber, which is a new material with excellent mechanical properties. Carbon fiber has no creep, fatigue resistance, low thermal expansion coefficient, and good corrosion resistance. More suitable for sealing valve stems with high temperature, high pressure, and frequent switching.

(3) Synthetic fiber series. This type of disc root is woven from high-quality synthetic fibers, with a fine structure and excellent high-temperature and high-pressure resistance, low thermal conductivity, and non flammability. Widely used in harsh environments with ultra-high temperature and high pressure, suitable for valves that work in combustion environments.

Shanghai Tingyang Self Control Anti Corrosion Valve Manufacturing Co., Ltd

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