Turbine start-up oil pressure
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During the turbine startup procedure, the start-up oil pressure should be reduced to zero while the emergency shutdown oil pressure is established. However, in my unit, the start-up oil pressure does not drop to zero and is instead as high as the emergency shutdown oil pressure. What is the reason for this? What are the potential hazards if this issue is not addressed over time?
The quick-close valve can be opened, but the starting oil pressure doesn’t drop; it’s really frustrating
Is the oil return flow for startup blocked? If the starting oil isn’t removed, how can the quick shut-off valve be opened!
I’ve encountered this situation as well; I suspect it’s a problem with the electro-hydraulic converter
When oil is supplied, there is a balance point between the start-up oil pressure and the quick-shut oil pressure. However, the start-up oil pressure drops quickly while the quick-shut oil pressure rises, which causes the quick-shut valve to open. There is pressure in both systems; then how does the quick-shut valve open? There is no feedback indicating that it has opened fully, so how can the machine be started?
Logically, if a quick-shut oil is established first and then the start-up oil is used, the quick-shut valve will not be able to release pressure and thus cannot be opened, which prevents startup. In a situation like this, in the event of an emergency, can you ensure that the quick-shut valve closes to enable emergency shutdown? Safety comes first; consult the manufacturer.
The starting oil has not been drained; why then would the quick-shut valve open? It can only be that the starting oil has not reached the quick-shut valve, which is why this situation occurs! Check the starting oil pipeline for any problems!
If it has dual intake valves, the oil pressure will return to zero only after both quick-close valves have been opened!
We opened both quick-close valves on site, and the starting oil pressure did not return to zero
If there is a chance to shut down the machine down, it is possible to check the spool valve inside the quick-shut control device