After the circulating convection type desuperheating water regulating valve was tried on the 100MW unit of Xi'an Yaochi Power Plant in 2004, its performance has greatly admired the leaders, specialists and on-site operators of the plant. Both the appearance, the leakage, the flow adjustment capacity and the service life are far superior to the well-known brand products imported from abroad.
Typical application of desuperheating water regulating valve in thermal power generating unit:
In the 300MW thermal power generating unit:
The boiler superheater has 2 sets of I-level desuperheating water control valves, and 2 sets of II-level desuperheating water control valves, which are used to adjust the temperature of the superheated steam.
In the reheater system, the desuperheating water regulating valve is used to adjust the temperature of the reheated steam slightly, as well as to reduce the temperature of the water spray in the accident state.
The high-pressure bypass system and the low-pressure bypass system, and the desuperheating water regulating valve achieve the steam desuperheating effect.
Circulating convection type desuperheating Water Regulating Valve:
The desuperheating water regulating valve is used to adjust the main steam temperature of the boiler and protect the heating area at all levels from over-temperature. Large-capacity power station boilers are necessary.
In order to ensure the practicability, effectiveness and flexibility of this kind of regulating valve, the selection of the desuperheating water regulating valve is particularly important, which involves the flow capacity of the valve in the engineering design and the selection and arrangement of the entire spray water desuperheating system.
The circulating convection principle and multi-stage pressure reduction structure control protect the valve components while ensuring reliable system performance.
Cavitation can be well controlled by controlling the fluid velocity, and the degree of erosion is proportional to the third or fourth power of the velocity. The circulating convection type desuperheating water regulating valve reduces the speed through multiple tortuous flow passages of the combined disc, thereby eliminating corrosion and avoiding damage to the valve trim and valve body. Each flow channel has a series of convection and turning, which can produce multi-stage pressure drop, which can reduce the velocity of the outlet fluid. At the same time, we adopt a sleeve structure with a combination of discs and windows. At the moment the valve is opened, there is a disc to eliminate cavitation to protect the valve. There is an upper window to meet the flow rate and stabilize the steam pipeline system.
Circulating convection principle, multi-stage pressure reduction structure
Adopting the principle of circulating convection multi-stage pressure reduction structure, so that the valve can effectively avoid cavitation and greatly extend its service life;
All the internal parts of the valve can be quickly disassembled and replaced, and the maintenance is extremely convenient. Maintenance does not need to cut and weld the valve body, which greatly saves maintenance costs and time;
The valve core and sleeve have good anti-blocking and anti-seizing performance. When the valve is frequently opened, a small amount of debris in the pipeline will not block the passage, and the valve core is not easy to jam;
Stem packing is imported high-quality products, zero leakage, no frequent replacement;
The spool sleeve material is matched appropriately, resistant to abrasion, abrasion, and seizure;
The valve seat and valve core seal achieves zero leakage, and the valve has a long service life;
Nominal pass: 3/4″～ 6″
Pressure rating: ANSI 150Lb ～ 2500Lb
Operating temperature: -29℃～575℃
Flow characteristics: equal percentage, linear
Valve body type: straight-through type, angle type
Leakage: Comply with ANSI B16. 104-1978 Class V, Class VI seal can be selected
Actuator: electric or pneumatic actuator
(Whether the electric valve or the pneumatic valve, there is a handwheel mechanism to ensure that it can be manually operated when the air or power is lost, and continue to maintain the adjustment function.)