Spring type safety valve
| Type | Safety Valve |
| Model | A68Y-P54110V, A68Y-P54140V, A68Y-P54200V, A68Y-P5432V, A68Y-P5445V, A68Y-P5464V |
| Nominal Diameter | DN 40-150 |
It is applicable for steam, air and other medium equipment or pipeline (working temperature ≤560℃ and working pressure ≤20MPa) as an overpressure protector.
- With spring full-discharge structure design, the valve has large discharge coefficient, simple structure, good sealing performance, accurate opening pressure, small blowdown, convenient adjustment and other characteristics.
- The valve seat is Laval nozzle valve seat. When flowing through the valve seat outlet, steam is up to supersonic speed and large discharge coefficient, capable of reducing installation quantity of safety valves on a boiler. With rigid alloy build-up welding, the sealing surface of the valve seat features abrasion resistance, erosion resistance and long service life.
- With thermal elastic structure, the valve disc uses its slight deformation for compensation under medium acting force to improve sealing capability and overcome advance discharge of the safety valve when medium pressure approaches the setting pressure. With advanced quenching technology, the sealing surface of the valve disc features improved hardness, abrasion resistant and corrosion resistance.
- Effect of the upper adjusting ring is to change flow direction of medium from the valve seat to change counter-acting force of medium on the valve disc. Position of the upper adjusting ring affects blowdown of the valve directly.
- An annular space is formed between the top of the lower adjusting ring and the lower plane of the valve disc. Pressure is changed by regulating space volume of the lower adjusting ring to reach proper opening pressure.
- Spring compression is adjusted by the regulating nut to make the valve obtain accurate setting pressure conveniently and rapidly.
- The backpressure adjusting sleeve is an auxiliary mechanism to adjust valve disc backpressure. Proper blowdown can be obtained via adjustment of the backpressure adjusting sleeve; adjust upwards to decrease backpressure and adjust downwards to increase valve backpressure.
- A cooling connector is set between the spring and the valve body to prevent the spring from impact of high temperature steam and ensure stable and constant elasticity of the spring.
- The spring is a crucial part determining performance of the safety valve. Different springs are designed for different setting pressures and blowdowns.
- The heat isolator separates the valve body from the spring to reduce heat impact on the spring, ensure rigidity of the spring and make performance of the spring stable.
