Cast steel stop valve is a key valve for controlling the flow of fluid in industrial pipelines. It has the performance characteristics of high temperature and high pressure resistance, and is more resistant to impact and corrosion than cast iron stop valves.
Leakage of cast steel stop valves can be manifested as leakage of the medium from the inside of the valve or leakage of the medium from the outside of the valve, referred to as internal leakage and external leakage.
Causes of internal leakage:
1. Wear or corrosion of the sealing surface ‌ Long-term scouring or corrosive media causes damage to the contact surface between the valve disc and the valve seat, and the seal is not tight ‌.
2. Impurity blockage ‌ Hard particles such as welding slag and rust are stuck between the sealing surfaces, scratching the sealing surface when closing or hindering complete closure ‌.
Causes of external leakage:
1. Stuffing box leakage ‌ Wear, aging or improper installation of the packing at the valve stem causes the medium to overflow ‌.
2. Leakage at the flange connection ‌ Loose bolts, aging gaskets or uneven sealing surfaces ‌.
After figuring out the cause of the leakage, we can solve the problem in a targeted manner.