Hai.

We have 2 GE 7 fa machines with base load capacity of 155 MW. When tested today, GT 1 went to 138MW and GT 2 only 132 MW. All the other parameters are normal except the exhaust pressure readings.

GT 1 exh.pressure= 8 in H20 TTRF 1-1317 deg c
GT 2 exh. pressure = 10 in H20. TTRF 1 = 1309 c.

Could the difference in the exhaust pressures cause the difference in MW? Previously the diff. of both units is only 2 MW at base load. I will give you full details again. If you need more details to solve the problem plz post here.

1) The value of TTRF1 for GT# 1 is 1321 deg c
GT# 2 is 1317 deg c previously at the base load.

2) We did not check this exhaust pressure in Mark-VI before. We used to check in the files and due to the location of the pressure gauge it is not accurate reading but there used to be about 10 mm h20 difference.

Plz reply. Thank you.

 

Hi Dear,

Can you send more details and your trends about ambient temp. and average of your TETC (exhaust temp.)?

 

Do you have catalyzers for NOx Reduction? If they`re stuck that probably raise you`re exhaust pressure and that could reduce the flow of the hot gas path. Maybe could affect your load too.