Comb-Cyc.Tube Repair
Comb-Cyc.Tube Repair
(OP)
With the rush of combined cycle units to our area,I was wondering if anyone had any suggestions on how the tube failure's will be delt with.Being they are in a bundle setup,tube to header,how will you repair or isolate tube failure.I have heard several idea's,none too convincing.Such as cutting into header's and plugging tube from both sides.Keeping in mind most of your tube and header joints are P-91&T-91,(requiring purge)Then welding window back in,also requiring purge.Other than that how will you even locate tube leaks.Anyone having worked on these new units have seen the tube bundles and know what I am talking about.Anyone?





RE: Comb-Cyc.Tube Repair
If you find a way to repair these tubes in less than a week's time, let us know and we will file a complaint to the respective HRSG vendor.
RE: Comb-Cyc.Tube Repair
With the onslaught of so many combined cycle plants (CALPINE alone had massive plans for constuction of 80 power plants) it was inevitable that these units were to be slapped together by inexperienced designers and fabricators. I have heard many stories of welding shops in Mexico that have never worked on anything more complex than a bicycle frame, suddenly welding T91 with temporary farm labor.............
My thoughts only !!
MJC
RE: Comb-Cyc.Tube Repair
RE: Comb-Cyc.Tube Repair
RE: Comb-Cyc.Tube Repair
It has got to be a gold mine for someone.
The designers of these CCGT plants in general never seemed to realize that these things were ever going to need to be worked on.
When maintenance issues become realiability issues (someone is busy cutting their way in, or welding their way out) just when the grid is screaming for megawatts, the luster of the low heat rates is going to be badly tarnished, and it will be some of the old boat anchor 30-40 year old central station units that have been condemned as having too high of a heat rate to run that are going to burn the gas to save the day, to the detriment of the ratepayers, of course.
RE: Comb-Cyc.Tube Repair
I don't know that there is any easier way than cutting your way in and welding your way out. But with regard to identifying the leaking tube we have a tool for just this task. It essentially perform a hydro on individual tube joints by sealing in side the tube and crushing a seal against the header face or tubesheet and pressures up 3000 psi.
Best Regards, Joey
www.spectool.com