PWHT boiler with tubes

[GenB]

I have the job to replace the furnace on a small boiler,
I have to PWHT afterwards,(a must on this job) Sec I boiler 150PSI
Q= will the tubes survive the 1150 F?
the tubes are newer and I do not mind to re-roll and but I do not want to replace them. Any one outthere who has
experienced this.
thanks in advance
genb

 

[metengr]

GenB;
This sounds like a closure weld PWHT. If the tubes are carbon steel they should be acceptable for service.

 

[GenB]

thanks metengr,
they are thing wall c/s SA178A .095 rolled and beaded
my concern is: will the tube ends will survive and will
not leak after PWHT,
I hate to get a surprise and have to replace the tubes
I do not mind roll and bead again but will they hold?
I know that in locomotive boilers the tubes were anealed after roll and bead but they were 10 ga or better.

I may try but it will be costly if it does not work.
thanks again.
genb

 

[metengr]

GenB;

they are thing wall c/s SA178A .095 rolled and beaded
my concern is: will the tube ends will survive and will
not leak after PWHT,

Yes, the tubes will survive. I would suggest you follow Section VIII, Div 1 post weld heat treatment ramp up and cool down rates to allow the tubes and tubesheet to move together.

I do not mind roll and bead again but will they hold?

Yes

 

[GenB]

I will try my best, thanks, GenB

 

[chicopee]

After beading the tube ends and do your hydro test, if the tube ends still leak, just seal weld them. I would not re-roll the tube ends if they leak because they are already strain-hardened and possibly enlarge the tube sheet holes. Also use a four roller tube expander not the three roller type.

 

[GenB]

Thanks, I will very careful.
genb

 

[GenB]

Thank you all,
the process was succesful,
a very light re-rolling was needed after PWHT,
Great advise, Thanks,
genb