Application and development of ceramic valves

Ceramics are characterized by heat resistance, corrosion resistance, wear resistance, high hardness, small deformation at high temperature and high sealing surface accuracy, etc. It has broad prospects to effectively use its characteristics as valve manufacturing materials.

In recent years, a variety of ceramic materials have been used in valve manufacturing. Ceramic valves generally use ceramics for all over-flow components, or important components (such as ball valves) use ceramics, other components (such as shells) lined with ceramics, or coated with ceramics on metal.

Application of ceramic valves

Ceramic ball valve

Ball valves can be used for flow control valves or shut-off valves containing corrosive or high-temperature fluids containing solids. All flow-through components can be selected to be ceramic for use, or only important components can be selected for ceramic spraying.

Ceramic ball valve structure, if the ball valve channel from a round hole into a triangular hole, the flow characteristics of approximately equal percentage, therefore, when installed on the valve positioner, can be used as a control valve. If the apex of a triangular hole is made into an angle, the range of amplitude changes greatly, and it is ideal as a regulating valve. However, if the corner does not die fillet, it will cause stress concentration, easy to crack, therefore, although made into the fillet, the regulating performance of the control valve slightly decreased, but still made into a fillet shape. At this point, the flow rate of the fluid through the control valve will increase, and aggravate the corrosion and wear, so it is more important to use and play the characteristics of ceramics.

Ceramic gate valve

In coal gasification equipment, high temperature and high pressure gas contains hard particles of coal and ash corrosive gas, in this very harsh conditions using ceramic gate valve is necessary. In the past, the valve made of metal made of cobalt chromium tungsten cemented carbide on the sealing surface could not meet the requirements. Now the metal is used on the high temperature withstand part of the shell, and the ceramic is used in the sealing part. Because of the unique structure to prevent the abrasion of micro powder, the service life of valves has been greatly improved.

Ceramic diaphragm valve

The structure of the valve is very simple, and its contact medium is made up of ceramic valve body and Teflon diaphragm.

The ceramic seat surface is accurately pressed and polished, which is completely pressed by the diaphragm and will not leak. As a supporting rubber lining material, fluorine rubber is used.

The ceramic valve body has smooth surface and little friction with the medium.

Ceramic cock valve

Ceramic plug valve consists of ceramic body and plug, sealing parts using Teflon, is a small flow resistance through the valve.

The contact medium part of the valve is the external lining of the ceramic monomer parts, which can not be deformed under the action of high temperature and high vacuum and permeable liquids.

The position of the valve seat is due to the wedge force of the ceramic cock, resulting in the necessary sealing pressure.

Development of ceramic valves

Both domestic and foreign valve manufacturers and research institutes attach great importance to the research and development of ceramics. In the future, the performance of ceramics will be higher and higher, and will become an economic material for valve manufacturing. For users, the brittleness of ceramics is still a defect, although the advantages of ceramics have a good understanding, but the actual use of ceramics is not very assured. In the future, it is still an important research topic for valve scientists and technicians to carry out strength analysis of ceramic components and establish failure probability calculation system while remedying the weakness of ceramics.