Plastic gate valves allow only unidirectional flow of the medium and are directional during installation. When connecting the flanges at both ends to the pipeline, tighten the bolts evenly to prevent flange deformation and leakage.
When opening and closing the gate valve, the force should be smooth and steady, avoiding impact. After the gate valve is fully open, the handwheel should be turned back slightly to tighten the threads and prevent loosening and damage. When the pipeline is used for the first time, there may be a lot of dirt inside. The gate valve can be slightly opened to flush away the dirt using the high-speed flow of the medium, then gently closed and reopened. Repeat this process several times to flush away the dirt before putting it into normal operation. The same method can be used to flush away any dirt that may be adhering to the sealing surface when closing a normally open gate valve, before fully closing it tightly.
If the handwheel or handle is damaged or lost, it should be replaced immediately. Do not use an adjustable wrench as a substitute. Some media may cause the valve components to contract after cooling when the gate valve is closed. The operator should close it again at an appropriate time to ensure no gaps remain on the sealing surface. If the operation is found to be too difficult, the cause should be analyzed. If the packing is too tight, it can be loosened appropriately. If the valve stem is misaligned, personnel should be notified for repair. Some gate valves experience difficulty opening due to thermal expansion of the closing element when closed. If opening is absolutely necessary in this situation, loosen the valve cover thread by half a turn to one turn to relieve stress on the valve stem, then turn the handwheel.
Plastic gate valves are wear-resistant, easy to disassemble, and simple to maintain. Valves installed on pipelines can be directly inspected and maintained online, effectively reducing plant downtime and lowering costs.
