A49H-40 Main Safety Valve

This valve is mainly used in power plant boilers, pressure vessels, and pressure and temperature reducing units to prevent pressure from exceeding the maximum allowable value and ensure safe equipment operation.

1. When the medium pressure rises to the set pressure, the impulse safety valve opens. The medium enters the piston chamber of the main safety valve through the impulse pipe, pushing the piston down and causing the valve to open automatically. When the impulse valve closes, the valve disc also closes automatically.

2. The sealing surface is formed by overlay welding with cobalt-based chromium-nickel stainless steel. The valve disc is heat-treated to improve wear and erosion resistance.

1. The valve must be installed vertically at the highest point of the equipment.

2. The main safety valve must be secured to a support that withstands the reaction force generated during steam discharge.

3. The steam discharge pipe must have dedicated hangers. Its weight must not be imposed on the main safety valve, and any additional prestress at the connecting flange between the main safety valve and the steam discharge pipe must be eliminated.

4. Drainage should be provided at the lowest point of the steam discharge pipe to prevent water hammer during steam discharge.