Structural Features And Applications Of Commonly Used Valve 2
(2) Stop valves and throttle valves:
Structural features of stop valves and throttle valves:
It is mainly composed of the valve body, valve cover, valve stem, valve disc and handwheel, etc.
Advantages and disadvantages of stop valves
Advantages: Good sealing performance, with low friction on the sealing surface
The phenomenon is not serious, maintenance is relatively convenient, and the opening height is high
The degree is small and the flow rate can be appropriately adjusted.
Disadvantages: High resistance to medium flow and long structural length
It is relatively large, with a greater opening and closing force.
2. Precautions
1) Stop valves are not suitable for regulating the pressure or flow of the medium. Throttle valves should be selected for parts that frequently need to adjust pressure or flow rate.
2) Straight-through and direct-flow stop valves and throttle valves can be installed on pipes that intersect horizontally or vertically. Angle stop valves and throttle valves need to be installed on pipes that intersect vertically. During installation, it is necessary to ensure that the indication direction of the valve body is consistent with the flow direction of the medium.
3) When the fluid flows upward through the valve seat, the tightness is affected when there is sediment on the valve seat. Therefore, it is generally not suitable for fluids with suspended solids.
3. Faults and Handling
(1) If the packing is exposed, replace the tight cover or stop the gas supply
(2) If the handwheel is too tight, loosen the cover or replace the packing
(3) Clean and repair the sealing surface for internal leakage
4. Daily maintenance: Cleaning, turning the wheel, and adding lubricating oil