Straight Stroke Regulating Valve Stem Is Thinner

It involves a simple mechanical principle: high sliding friction and low rolling friction. The valve stem of the straight-stroke valve moves up and down, and the packing is slightly compressed, it will wrap the valve stem tightly, resulting in a large return difference. For this reason, the valve stem is designed to be very small, and the packing is usually made of tetrafluoro packing with a small friction coefficient to reduce the return difference, but the problem is that the valve stem is thin, easy to bend, and the packing life is short. The way to solve this problem is to use a travel valve stem, that is, an angular stroke control valve. Its valve stem is 2 to 3 times thicker than the straight stroke valve stem, and the graphite packing with long life is used, and the valve stem has good rigidity. The packing has a long service life, and its friction torque is small and the hysteresis is small.