ceramic backing bars

Date 03-27-2008 15:21

my company is about to bid a job with a lot of full pen field welds. they have asked me to research ceramic backing bars. have any of you guys used them? can they be reused or are they a one shot deal? any suggestions for any other reusable non-metal backing? they are trying to avoid steel backing because all backing must be removed and brass and copper would have to be backgouged and there won't be room to do it.

By swnorris (****)

Date 03-27-2008 16:08

They are a one shot deal.

By CHGuilford (****)

Date 03-27-2008 16:29

Do you mean ceramic backing bars, or is that ceramic backing tape?

If you mean tape then that really is a one shot deal for the most part. However, the ceramic removes easily. If you get the kind with a shallow groove in them, they shape the root so it is possible to get a weld that doesn't need to be ground up or backgouged.
So in that sense, they can save you time and money.

We have been able to get som limited re-use of ceramic tapes by applying them to an aluminum bar that is laid down on a table, then the plates to be butt-welded were laid on top. But that was 1/4 material and CJP was desired but not required. Even still, we didn't get much more than 2 shots with the same ceramic tape.
Safest bet is to estimate 1 foot of tape for every foot of weld.

By BMason

Date 03-27-2008 16:41

either bars or tape. i'm not sure which would be better to use( if either at all). this is a structural project so the backing would have to be heavy duty

By mpitt

Date 03-27-2008 16:52

If the welding is done to D1.1 you will have to qualify the procedure by testing or backgouge and weld the root.

By makeithot (***)

Date 03-27-2008 23:18

I'd use the tap myself because the bars still need to have a channel tacked on to hold them in place this can be reused but the backing can't.