Ceramic Tape??

Date 12-10-2008 19:10

Basically what the subject says, ceramic tape? Looking for education on it, what it's used for, advantages and so on. Talked to my Uncle today, welding for 30+ years and he said, never heard of it. He does pressure vessels, boiler and so on.

He was as curious about it as I am. He figured maybe it was used on pipe so as not to interupt the steam flow. He also told me about inserts shaped like a t that would go in the root and the inner piece would be left in the pipe so he thought maybe the ceramic tape would drop off and be blown out somehow so you would'nt have the root bead in the tube to interfere with the flow.

But, neither one of us knows so I came to the site where a bunch of my questions have been answered. So what's the deal with ceramic tape? The process I talked to a guy about was using mig in a structural manner, flux cored wire, believe he said .045. Can it be used with another process, tig, stick? Just out to learn all I can since I have a deep interest in just about anything to do with welding.

Thanks,

Shawn

By hogan

Date 12-10-2008 19:38

Cumminsguy71,
I believe that you are talking about backing material. Ceramic with an adhesive on it to be used as backing when making a weld. It is similar to using brass, or a steel backing bar. I don't see it being used on boiler and pressure vessel work. It usually comes in rectangular shapes, although there are others. This would be difficult to put on the ID of an open root pipe weld. It is allowed to be used in AWS work, but need to be qualified. Typically the adhesive will hold until the roots complete. It can be helpful when you need to make a full pen weld with an open root ( plate, beam, something flat) and don't have the ability to leave, or remove backing when needed. Also, it is sometimes used to bridge a gap.

By Metarinka (****)

Date 12-10-2008 19:42

hogan nailed it, They also use it because there's not any potential effects of melting the backing to the weld, as could happen with aluminum or copper backing. I've used it only once on a open root plate weld.

By jwright650 (*****)

Date 12-10-2008 20:03

Hogan has it right, the only comment that I would add to his is about the need to be qualified....if you try to use it for backing and perform welding on one side of the joint only, then you must qualify a welding procedure.

....however if you address the second side of the joint by back gouging to sound material and then re-welding the second side, (in my opinion) then it doesn't need to be qualified.

By Cumminsguy71 (*****)

Date 12-10-2008 20:57

Ok, I think I get it. If you used copper or aluminum some of that metal may melt and essentially contaminate the weld? More or less? Yeah, my Uncle and I were talking about ship work on a job I called about and they asked about the ceramic tape backing strip and talked to him to see what he knew of it.

I was just curious as to what it was used for, why/the purpose/choice of it's use. Thanks all for the education.

Shawn

By jrw159

Date 12-10-2008 21:02

Shawn,
I can't add much to the great answeres you have received, but here are a few links for you. Maybe you have already seen these, but here you go.

http://www.gullco.com/more_katbak.html?gclid=CLOXzrz4tpcCFQMCagodxgvkiQ

http://www.dabotek.dk/keramik/keramik.htm

http://www.directindustry.com/prod/huntingdon-fusion-techniques/ceramic-backing-material-for-welding-40305-330171.html

http://www.nst.no/english/Datasheets%20pdf%20uk/Ceramic%20backing%20v1%20011203.pdf

jrw159 :-)