Sequence of opening the turbine quick-shut valve and the medium-pressure steam manual valve
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After warming the pipes with medium-pressure steam, we open the quick-close valve and then the manual valve for medium-pressure steam, before proceeding to start the machine. I would appreciate it if experts could tell me what the consequences would be if the order is reversed.
What is the procedure for opening the quick shut-off valve and then the medium-pressure steam manual valve? How do I warm up the pipes for manual valves and quick-close valves?
There should be a vent valve near the quick-shut valve, right? First open the hand valve, then the quick-close valve; open the vent valve. Once the pressure is normal, start the steam turbine and close the vent valve.
First, open the manual valve to warm up the pipeline ahead of the quick-close valve; once the pipeline has been warmed up, then open the quick-close valve in preparation to start the machine
I’d like to add that, in the pipe warming mode, the medium-pressure steam manual valve is opened by 2-3 turns, and the pipe is vented before the quick-close valve.
Then open the speed control valve, fully open the manual valve, start the steam turbine, and close the vent valve. The order in which the quick-close valve and the manual valve are opened is reversed – will this have any impact?
We have always kept the steam hand valve fully open after warming up the pipes, and followed the startup procedure to introduce start oil – quick-shut oil – secondary oil – and then start the machine.
After warming the pipes, fully open the steam manual valve; follow the startup procedure to introduce start oil – quick-shut oil – secondary oil – and then initiate operation. Proceed through stages 1, 2, and 3 of warming up, reach critical conditions, and once the machine is running properly, close the steam valve for venting.
The main steam valve has a bypass line, but it is not recommended to open the quick-close valve first and then the main steam valve, due to concerns regarding leakage from the speed control valve
It is not possible to verify whether the quick shut-off valve can completely cut off the flow