The flow medium of the gate valve can be clean water, sewage, sludge, scum, oil or gas. Its circulation diameter is generally 50~1000mm, and the maximum working pressure can be larger than 2~4MPa.
The characteristic of the gate valve is that the passage is completely barrier-free when the valve is fully opened, so the resistance of the fluid passing through the valve is minimal, and there will be no entanglement, so it is suitable for use in sewage and sludge pipelines containing a lot of impurities. However, the gate valve has the disadvantages of long sealing surface, easy to leak, and large volume.
The gate valve is composed of a valve body, a gate plate (also called a plug-in plate), a seal and an opening and closing device. Because 6-12 shows a single gate valve. The opening and closing method of the gate is reciprocating translation. In order to prevent leakage, the two planes and two sides of the gate must form a good seal with the valve body. Therefore, a narrow and long gap between the valve body and the gate must be inlaid with Bronze, rubber or comb tooth shape. The opening and closing device of the gate valve has open rod and concealed rod, which can be divided into manual, electric or hydraulic.