tig welding z core

By Idaho welder Date 02-08-2008 18:16

Hi I have been reading through the posts and there is some good information in here. I really respect you guys that take time out your day to help answer the questions that come up. I'm the QC manager in a large chemical plant in Idaho. I graduated from the local collage in town with a degree in welding and did a 5 year apprenticeship in the local pipe fitters union. Today we have a problem in our sulfuric acid plant. We are making a repair on our acid system and have to re weld a pipe using Z-Core welding rod. The process we are using is GTAW and the weld keeps cracking. We are using a 200 degree pre heat and 400 degree interpass temp. Have any of you used this rod and if you have can you give us any advice. The snow is knee deep and its cold here and if we don't get this repaired we run the chance of freezing the plant up.

By JescoPressure (**)

Date 02-08-2008 19:06

is it carbon steel? or stainless 300 series? if carbon you might have to do a high temp bake out on the material . I would assume it is carbon with your preheat temp. What about post heat and wrapping if its cold enough?

By Idaho welder Date 02-08-2008 20:13

Its not carbon. There is no chemical comp. on the tube of rod, no AWS #. I went to the web site and all it says is that it has good weldabilty. No welding procedures in document control form the company that installed the pipe. I think we will fab a new spool out of a different material get the plant running and do some more research. Thanks for the reply.

By ssbn727 (*****)

Date 02-09-2008 06:28

Hi Idaho welder!!!

First of all, "Weldcome" to the forum!!!

The one thing that you haven't mentioned yet is the grade of base metal you're welding on... Since you're going to opt to fab a new spool then, I guess you already found your solution. Let us know how it works out :)

Respectfully,
Henry

By Idaho welder Date 02-11-2008 14:25 Edited 02-11-2008 14:28

Thank you guys for the welcome I appreciate it. From what I have read in here there are some sharp guys taking time from there work day to help others. The pipe we were welding on was called z-core no #'s on the pipe you could read. We fabbed a new spool out of hastalloy and got the plant running. I was reading in one of the forums that guys were looking for info on the API tests. I have a 510 and 653 and would be happy to share the study tools I used getting ready for the tests. Hope everyone has a great day.