3" Sched 80 Question

Date 07-16-2004 02:28

Hey,

I'm working on some 3" schedule 80 carbon at school and im experimenting on different ways to fill and cap this pipe. I've gone from doing (tig all the way out)root, hot, 2-3 3/32 fillers and a weave bead cap, to root, hot one 1/8" filler and either weave cap or 3 bead cap.

It seems that when i did the 1-1/8" filler i got a lot of trash that made its way onto my cap, and seems to be between each step on my cap.

What ways would you suggest on filling and capping this pipe?

By Niekie3 (***)

Date 07-18-2004 18:57

Hi

What do you mean by "trash"?

Regards
Niekie

By wrangler97 (*)

Date 07-19-2004 01:16

i mean the bead isnt clean like there is little peices of "trash"(i guess trash from wire or actual trash in the pipe?)

By Niekie3 (***)

Date 07-19-2004 05:40

Hi

If you are welding with SMAW, then there is obviously slag on the top of the weld bead after each pass. When removing this, the weld bead should have an evenly rippled surface without any holes etc. If you are picking up holes etc, then it may be that your welding with the 3.2mm rods are not quite right. (It is difficult to weld nicely with 3.2mm electrodes on 3" pipe, especially if you are in the 5G or 6G position.)

Also keep in mind that low down in a "V" prep, the SMAW slag does not easily come off. You may have to just "dress" it with a grinder to get it off nicely.

Regards
Niekie Jooste
Fabristruct Solutions

By billvanderhoof (****)

Date 07-20-2004 04:17

Hi Niekie-
Haven't been seeing you here much lately, hope you've been well.
Bill

By Niekie3 (***)

Date 07-20-2004 07:14

Hi Bill

Yes, just been so busy that I have had little time for anything other than work!

Regards
Niekie

By wrangler97 (*)

Date 07-20-2004 18:12

i was tig welding the pipe all the way out, now im on to 2 inch sched 40, that is challenging.

I just figured that the way i ran was that i did one half a weave bead and on half a 3 bead cap, i did one whole side at a time so all of that heat on one side of the pipe played a part in the trash.