- Feb 14, 2019-
|As a kind of gate valve, carbon steel gate valve can be divided into wedge gate gate valve and parallel gate gate valve according to the sealing surface configuration. The wedge gate gate valve can be further divided into: single gate type, double gate type and elastic gate type; Parallel gate gate valves can be divided into single gate type and double gate type. According to the thread position of the valve stem, it can be divided into two types: open gate valve and dark gate valve.|
When the carbon steel gate valve is closed: the sealing surface can be sealed only by the medium pressure, that is, the sealing surface of the ram is pressed against the valve seat on the other side by the medium pressure to ensure the sealing of the sealing surface, which is self-sealing. Most of the gate valves are forced to seal, that is, when the valve is closed, the external force is forced to press the gate to the valve seat to ensure the sealing of the sealing surface. The gate of the carbon steel gate valve moves linearly with the valve stem, called the lift gate valve. Usually, trapezoidal threads are provided on the lifting rod, and the rotating motion is changed into a linear motion by the nut at the top end of the carbon steel gate valve and the guide groove on the valve body, that is, the operating torque is changed to the operating thrust.
When the carbon steel gate valve is opened, when the lifting height of the gate is equal to 1:1 times the diameter of the valve, the passage of the fluid is completely unblocked, but this position cannot be monitored during operation. In actual use, the apex of the valve stem is used as a mark, that is, the position where the valve is opened, as its fully open position. In order to consider the temperature change, the lock phenomenon is usually turned on to the apex position, and then back to 1/2-1 circle as the position of the fully open valve. Therefore, the fully open position of the valve is determined by the position of the shutter.