Tube plugging
Tube plugging
(OP)
Hello
My question is there any standard or reference which gives exact guideline that whether we have to puncher a tube before plugging. This is the case of boiler where we have leak in a bend.
now can i remove the bend and plug the tube or i have to puncher the tube then plug it.
My question is there any standard or reference which gives exact guideline that whether we have to puncher a tube before plugging. This is the case of boiler where we have leak in a bend.
now can i remove the bend and plug the tube or i have to puncher the tube then plug it.





RE: Tube plugging
RE: Tube plugging
tube is in economizer panel.
RE: Tube plugging
http://www.tandfonline.com/doi/abs/10.1080/0145763...
-Christine
RE: Tube plugging
RE: Tube plugging
Regards
r6155
RE: Tube plugging
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P.E. Metallurgy, Plymouth Tube
RE: Tube plugging
RE: Tube plugging
Regards
r6155
RE: Tube plugging
RE: Tube plugging
RE: Tube plugging
You can get PCC-2 from ASME.
https://www.asme.org/products/codes-standards/pcc2...)
It is also available on IHS provided that your subscription covers it or you purchase thru them.
I do not condone theft of intellectual property, and as copyrighted material it would be illegal and unethical for anybody to share a copy with you or anybody else. If the $139 price is too much, then I suppose the heat exchanger you are working with is not particularly valuable to the plant either...
RE: Tube plugging
I thought about posting an excerpt of the paragraph, however for the reasons jte mentioned I decided against it. As jte mentioned it doesn't cost that much and if your company owns and maintains pressure equipment it is a good reference to have on hand anyways.
RE: Tube plugging
RE: Tube plugging
RE: Tube plugging
Ethics matter. Thanks guys
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P.E. Metallurgy, Plymouth Tube
RE: Tube plugging
But i appreciate efforts put by respected members
RE: Tube plugging
RE: Tube plugging
The dowel is then pushed down the leaking tube until one of the clearance halves has passed the leak, at which point the efflux of water will cause the wood to expand tightly against the ID of the tube, sealing the leak and allowing the boiler to be returned to service.
Since there is no gas flow through the tube, there is little danger of the wooden plug ever charring unless it is very close to the "hot end" tube sheet, in which case it may be necessary to parge over the end of the tube with a bit of refractory cement.
Hope this helps someone.
CR
"As iron sharpens iron, so one person sharpens another." [Proverbs 27:17, NIV]
RE: Tube plugging
Tapered tube plugs simply driven into the ends of the tubes can fail and be ejected with deadly force.
I have seen a couple of procedures from boiler manufacturers that use a stay rod through the length of the tube to hold the plugs in place so they cannot be ejected.
A tapered plug should only be used when it is in an application where the pressure of the boiler will be acting to drive the plug securely into the tube (i.e.: plugging of generating tubes in the drums of a water tube boiler).
We've also removed tubes from service by capping with the use of a butt weld or socket weld cap sized to fit the tube. This would be like for removing a superheater or economizer element from service. Cut the tube stubs near the header and install the caps to remove the leaking or wasted tubes from service.
Caution should always be used when using this method as well. A capped tube stub that is exposed to radiant or convection heat can overheat and fail because the steam or water flow has been cut off.
If you're going to cap a tube stub make sure it's out of the gas path. If this is not possible, hire an engineer to design a plug that can be installed directly into the header.
As always, make sure your AI is on board with the repair plan.
numberfive
RE: Tube plugging
I don't think the rules go far enough. Apparently, many repair organizations lobbied against any rules being addressed in the NBIC. So we get a compromise.
RE: Tube plugging
When a tapered plug was "driven" into tube-end to plug a leaking tube many jurisdiction did not even consider this a code repair as no welding was required...owners might even perform such "temporary" repairs. I always heard when plugging tube by this method that you needed to make a good hole (blow a hole with a torch) in the tube to prevent pressure from possibly building-up in the tube and blowing the driven plug out.
In recent years I've seen much discussion about what material is required for the tube plugs - SA-105 has stress value equal to SA-516-70 (drums) whereas SA-36 material has lower stress value.