Design and manufacture standard: Design and manufacture standard：
Nominal diameter: 2 1/2"(DN65)
Nominal pressure: 4500LB
The design, manufacturing and testing meet the requirements of ASME I, GB/T 12243 and ASME B16.34.
Structure feature and advantage:
1. The valve seat is designed to the shape of de Laval nozzle, with the addition of adjustable double adjusting rings, at the opening of the safety valve, the reactive force produced by steam and the expansion force of steam medium can be used to help the valve open at full discharge, so it has large coefficient of discharge.
2. According to actual working conditions, valve clack can be designed to be special elastic valve clack and rigid valve clack. The seal test pressure of rigid valve clack can reach 93% set pressure, and the seal test pressure of elastic valve clack can reach 96% set pressure.
3. It can be realized by adjusting the valve seat adjusting ring and guide sleeve adjusting ring that the overpressure is less than 3% and the blowdown reaches 4%-7%. In addition, the blowdown can be adjusted through backpressure cavity adjusting mechanism.
4. The valve seat sealing surface is made of hard alloy by build-up welding with such characteristics as wear resistance, erosion resistance, and long service life.
5. Open type bonnet and the radiator provided between valve body and bonnet can prevent direct contract between steam and spring at discharge, thus reducing the temperature of spring.
6. Special materials of guide sleeve, valve clack, and valve clack seat, strict requirements for geometric tolerance and finish, rigorous spring rigidity control, and the design of open-type bonnet ensure that the valve can release accurately each time.
7. Valve clack plug for hydro test can be subjected to strength test on site.
8. Travel switch for safety valve release and steam exhaust signal can be provided as required.
9. Each valve product is tested for thermal properties at delivery.