Hello ,

In a MHI Steam turbine, the manufacture operation manual states that the turbine has a TTV and four dump solenoid valves for control oil draining. however the customer provided a starting procedure as all starting permissive must be satisfied includes the SOV which responsible for control oil drain to be closed and the TTV valve in close position. after that the operator will press a PB to open the TTV. my point here that if the SOVs valves are closed, the control oil header pressure will have a sufficient oil header pressure in which accordingly the TTV will automatically open.

Could anyone please advise if there is any other scenario to meet the customer requirements.

 

Hello ,

During startup as you said dump valves closed position when operator give pb to open control oil system will be pressurized.
For TTV OPERATION also control oil pr when sufficient oil pressure is there spring will charged valve will be open

If spring fails or control oil pressure killed valve will be close

IF turbine in operation if you want to do TTV stroke test that time TTV solenoid will be energised (DRAIN THE OIL ) valve will be close (that time steam flow will share to other valve) solenoid deenergise valve will open