During the opening and closing process of the valve, the valve stem bears tensile, compressive, and torsional forces, and comes into direct contact with the medium. At the same time, the filler also has relative frictional motion, which has sufficient strength, good impact toughness, wear resistance, and corrosion resistance at temperature.

The connection between the valve stem and the ball, as well as the contact between the valve stem and the valve body, should have anti-static devices to prevent static electricity from accumulating on the ball. The safety design of the valve stem should prevent it from being "blown out" under working pressure, and the flange on the valve stem should be treated with an annular ring to reduce the coefficient of friction.

The characteristics of traditional valve stem processing technology:

1. Traditional valve stem threads use spiral flying knives, resulting in inaccurate thread accuracy; Traditional chip free rolling threads are prone to damage to the rolling die, deformation, and distortion.

2. The accuracy of the grinding machine is not high and requires a long time.

3. The closed position uses double clamping and flipping to pull down the seal, resulting in poor concentricity and easy leakage of the seal.

4. The end is indexed by the indexing plate of the milling machine, which is slow to process, cumbersome and time-consuming