This kind of tungsten carbide sealing ring is made of the same material, the performance of the material is uniform in all parts of the sealing ring, there is no composite sealing ring leakage and separation defects, there is no possibility of electrochemical corrosion. Most soft rings are made of graphite, while hard rings can be made of various alloy steels, such as bearing steel (GCr9), high-speed steel (W18Cr4V) and other alloy steels (such as 1140Cr, 3Cr13, etc.), and some are made of alloy cast iron. (such as silicon, chromium and nickel cast iron). These materials should be supplemented by appropriate heat treatment processes to improve their hardness and wear resistance. These materials cost less and, if used properly, have a longer life. In order to further improve the hardness and prolong the service life, cemented carbide can be used. The commonly used cemented carbide is cobalt-based tungsten carbide with better performance but high price. The price of steel-bonded carbides is lower. In order to improve the corrosion resistance in the corrosive medium, there are nickel-based tungsten carbide, and hastelloy alloy has higher corrosion resistance, but the price is expensive. In addition, there are seals made of silicon carbide and other ceramic materials.

Combination seal ring

Tungsten carbide and other materials have excellent properties, but the high price, difficult processing, limited its use. In order to solve this contradiction, tungsten carbide seal ring  appeared. The sealing end face is made of cemented carbide, and the base of the sealing ring (called ring seat) is made of ordinary materials. In order to solve the connection and sealing between cemented carbide ring and ring seat, there are four kinds of combined sealing rings, which are hot-mounted type, ring-type, welded type and brazing type.

Sealing ring requirements:

Sealing ring is the general name of moving ring and static ring (the same below), is the most important component of mechanical seal. Seal ring to a large extent determines the mechanical seal performance and life, so it put forward some requirements.

1. Sufficient strength and stiffness. Under working conditions (such as pressure, temperature and sliding speed, etc.) is not damaged, deformation should be as small as possible, working conditions fluctuations can still maintain the sealing.

2. The sealing end face shall have sufficient strength and corrosion resistance to ensure a satisfactory service life under working conditions.

3, sealing ring application of good heat shock resistance. Therefore, the material is required to have a higher thermal conductivity coefficient and a smaller linear expansion coefficient, so that it will not crack under thermal shock.

4, sealing ring matching should have a small coefficient of friction and good self-lubrication, sealing ring material and bee fluid should have a good wetting. If short dry friction occurs in the work, the sealing end face will not be damaged.

5, sealing ring should strive to be simple, symmetrical and give priority to the overall structure. Can also be used in combination (such as mount type) sealing ring, as far as possible to avoid the use of sealing end spray structure.

6, sealing ring to be easy to manufacture, installation and maintenance to be convenient, low price.

Seal ring is a ring seal with a gap, by being compressed after the elastic and against the static parts of the inner hole wall sealing role. Sealing ring is a kind of ring seal with a gap, put it in the ring groove of the sleeve, the sleeve and the shaft rotate together, the sealing ring is pressed by the gap after the elastic and against the static part of the inner hole wall, can play a sealing role. All contact surfaces shall be hardened and polished. The sealing ring is made of wear-resisting cast iron containing chromium and can be used for sliding speed less than 100m/s; If the sliding speed is within the range of 60 ~ 80m/s, the sealing ring can also be made of tin bronze.

Related link:

http://www.wococarbide.com/Transaction/en_information.html

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