3 replies to this topic

[h.eghbali]

Dear all.

Hello.

I have a question.

We have a steam turbine which operated with high pressure steam (HPS). Min and Max pressure and temperature of HPS inlet is given in Vendor catalogue (min P= 39 barg, Max P=41 barg) (Min T=390 C and Max T=410 C).

Unfortunately HPS operating condition fluctuates frequently, so that T decrease to 320 C and P decreases to 18 barg (without turbine trip!). I'm surprised what is the actual effect of this variation on steam turbine? 

We are assumed that everything is ok! because turbine wouldn't trip. what consequences would you have expected?

Thanks in advance. 

[PingPong]

You don't mention the outlet of the turbine.

Is it a backpressure turbine? Or does it have a condensor?

Does the vendor specify the turbine efficiency?

 

Find out what the outlet pressure and temperature of the turbine is during various inlet conditions.

 

Plot the inlet and outlet conditions on an H-S diagram (Mollier diagram)

and see on the diagram how much (if any) condensation there is

and check with vendor whether that is acceptable.

[breizh]

Hi,

Consider this calculator to support your study .

Steam Calculators: Steam Turbine Calculator (energy.gov)

 

Definitely a good idea to consult the turbine manufacturer .

 

Breizh

[horatorres]

Sure  that the efficiency and the power outlet will decrease due to the input energy reduccion.  Calculate it , to figure out, I will do and let you know.

 

I suggest that you control the steam turbine vibrations in  low inlet pressure events; depending on the mechanical design of the machinery, sometimes an unbalanced force creates vibrations due to the low inlet pressure.

 

Horacio