I am working as control room operator on GE frame 9e gas turbine last 9 years. I have a question regarding force cooling of machine via crank continuously running around 10 hours.
For achieve wheelspace temperature and force cooling time, we start both 88BT AND both 88TK fans. Manager do it for his efficiency to not loose time of shutdown and fast startup.
My consideration, is this good for a long term of machine auxiliaries?
Yes during force cooling time we monitor winding temperatures of cranking motor.
Its reach around 104 Celsius maximum. Its high alarm on 140 celcius and high high alarm 160 Celsius.
on high high crank trip.
I don't really see any big deal with this.Running 88BT. I'm not so sure, it can cause uneven cooling. Take a look at your P&ID, I don't think that running 2xTK fans is any better than running one only? You are monitoring the Starting Motor temp. which is good. Why are you taking 10 hours to do this, It seems long? What criteria are you using to determine when you are cool?
How frequently are you doing this?