A valve is a spherical type, that is, a concave type, a […]
A valve is a spherical type, that is, a concave type, and the valve is characterized in that the surface is in contact with the ball, which is advantageous for sealing;
The other type of valve is cylindrical, the valve is easy to process, and the valve and ball are line sealed, which requires higher precision for the ball and valve.
Stainless steel balls for valves, usually 304 stainless steel balls, 316 stainless steel balls, 440 stainless steel balls, 304 has the advantage of being relatively cheap and has good rust resistance. 316 has better rust and corrosion resistance than 304, such as Sea water, as well as corrosive liquids, corrosive gases should choose 316 stainless steel beads or 316L stainless steel beads. Of course, if the valve pressure is relatively large and the accuracy is high, then 440 materials must be selected because 440 stainless steel balls have High hardness, high precision, hardness up to HRC58, hardness can reach G10.
Of course, if there are higher requirements for valves, such as those used in petroleum equipment, hard alloy balls are used. Carbide balls are also widely used in various valves, which have good wear resistance and corrosion resistance, but Carbide balls (tungsten steel balls) have two characteristics. One is high hardness, which is afraid of high and low temperature changes, that is, fear of sudden cooling and sudden heat, and there is a big difference, density is 14.9-15.1, which is not suitable for part. Valves, that is, gas or liquid can not afford the valve.
Ceramic balls are also a good type of ball for valves. Ceramic balls have the characteristics of light specific gravity, high hardness, high temperature resistance, corrosion resistance and wear resistance, especially silica ceramic balls, but the cost is high.