The types of cast steel gate valves can be divided into 1, wedge gate valve and parallel gate valve according to the sealing surface configuration.
Wedge gate valves can also be divided into: single gate type, double gate type and elastic gate type; Parallel gate valves can be divided into single and double gate valves. According to the position of the screw thread of the stem, it can be divided into two types: open stem gate valve and dark stem gate valve.
Installation and maintenance of cast steel gate valves shall pay attention to the following matters:
1. Handwheel, handle and drive mechanism are not allowed to be hoisted, and collision is strictly prohibited.
2. Double gate gate valve shall be installed vertically (i.e. the stem is in the vertical position and the handwheel is at the top).
3. Gate valves with bypass valve should open bypass valve before opening (to balance pressure difference between inlet and outlet and reduce opening force).
4. The gate valve with drive mechanism shall be installed according to the specifications of the product operation manual.
5. If the valve is frequently switched on and off, lubricate at least once a month.
Cast steel gate valves have the following advantages:
1. The fluid resistance is small, and the sealing surface should be brushed and eroded by the medium.
2. There is no restriction on the flow direction, no disturbance and no reduction of pressure.
3. Simple shape, short structure, good manufacturing technology and wide application.
Of course, gate valves also have disadvantages as follows:
1. The sealing surface is easy to cause erosion and abrasion, and maintenance is difficult.
2. The external dimension is large, which requires a certain space to open and close for a long time.
3. Complex structure.
Although simple, but these cast steel gate valve knowledge is not to be ignored.
For more information about cast steel gate valves, please consult: www.sz-sport.com