Common out of control phenomena of stainless steel check valves include backflow, loose closure, and abnormal vibration. Do you know how to deal with these situations?
1. Valve backflow (medium backflow)
Urgently stop the pump, close the upstream and downstream valves, and then check if the valve body arrow is reversed (reversal rate>60%). Afterwards, reinstall or install a second check valve according to the flow direction.
2. Inadequate closure/internal leakage
Knock the valve body shell to shake off impurities, then remove the valve and clean the oil/water stains on the sealing surface (nylon brush+acetone). Afterwards, replace the sealing gasket/weld repair the worn valve seat.
3. Severe vibration/abnormal noise
Reduce the opening of the outlet valve to decrease the flow rate, and then check if the pipeline support is loose. Afterwards, install a water hammer eliminator or replace the micro resistance slow closing check valve.
4. The valve disc is stuck and unable to move
Gently tap the side wall of the valve body with a copper rod to loosen it, disassemble and remove rust residue (do not use a wire brush to scrape stainless steel). Afterwards, replace the corrosion-resistant valve stem or install a pipeline filter.
It is prohibited to use hydrochloric acid for rust removal (food grade citric acid), the sealing surface should not be coated with ordinary butter (food grade silicone grease lubrication), and valves should not be installed in reverse (valve arrows should always face the direction of the medium flow).