The maintenance of relief valve
2015-09-21 by bridge
Through a sub-critical 600MW Steam Turbine five kinds of variable condition under the operating conditions of the control
relief valve to adjust the stages given numerical study and analyze the three-dimensional steady flow and pressure loss characteristics, the following conclusions:
1)Safety Valve Burner Valve- regulating the flow of the stages is complex and there is a strong spin flow. relief valve throat will have a greater throttling losses; relief valve disc below the "hole" area and relief valve inlet pipe downstream portion of the inlet area is full of strong vortex, also caused greater pressure loss.
2) When the four relief valve fully open, the steam will be filled with all the relief valves, high pressure pipe, with steam chamber and adjustable level cascade, regulating
Gas Control Valves - good flow performance tuning level segment; when a relief valve is turned off , corresponding to the relief valve steam distribution chamber and a nozzle group without steam flows from the buckets into the steam inlet arc to a non-arc process, rotor blade passage is drawn into the fluid inlet non-the chamber and the corresponding nozzle cascade, the formation of a large amount of swirl in the chamber, causing a higher pressure loss region.
3) within the flow conditioning level showed obvious non-axial symmetry. Unopened and partially open pilot operated safety valve adjustment level corresponding chamber, nozzle group and rotor blades, the total pressure losses are relatively large.