Structural welding on 4" drill pipe

By shorthood2006 (****)

Date 12-13-2008 00:04

if it is really drill pipe(used to drill oil and gas wells) good luck...it typically is magnitized. IT is a #%&^@#@& to weld!

By stkwldr (**)

Date 12-13-2008 00:20

use 7018 rod

By RioCampo (***)

Date 12-13-2008 00:58

Sometimes you can heat it with a rosebod till it glows, then wrap your ground around the pipe. Weld it with 7018, it will probably be magnatized like darren said.

By Arctic 510 (**)

Date 12-13-2008 01:04

I was going to give you some wisdom, but RioCampo has got it nailed. I welded some tire rim hangers onto drill steel that had been driven into the ground for 789 haul truck tire rims (heavy) at a mine I used to work at. I used tons of preheat, wrapped my ground, and used 7018 H4R rod. Lots of weight and the structure I welded to the drill steel takes a beating.

Have fun...

By raftergwelding (*****)

Date 12-13-2008 01:21

I've done the preheat deal but not the lead wrap afterwards and the stuff i built is still up today but i didnt warranty it thats for sure and the customer agreed to my conditions got lucky i guess

By Iron Head 49 (***)

Date 12-13-2008 10:50

Just adding to the list of tricks already posted.
Make your first pass with 6010. Also any Innershield wire that runs DCEN, say like NR-212, NR-232 is a big help with arc blow!

By raftergwelding (*****)

Date 12-13-2008 15:48

Ihave also just burned the rod real hot and it works but ya gotta be fast or it looks like hell if it's really heavily magnetized you can try reversing polarity for the root and the run regualr with 7018 i have had some where i just grabbed another joint and kept goin

By Superflux (****)

Date 12-13-2008 22:22 Edited 12-13-2008 23:59

Never seen the spec sheet, but have been told by Tool Pushers that it is 4140 steel. I've had good luck welding it with 7018 and (heat back about a foot to dull red and let it cool) 400-600 pre-heat (cattle guards in the patch) cuz us poor-boys weren't about to splurge for alloyed rods. Like Rio Campo suggested, the pre-annealing seemed to help on the magnitizing /arc blow. Once a D 9 side boom drives over it, the warranty is void.
When welding on subsea castings (4140 to A106 pipe) for National Supply, we used 11018 C1 with a 600 preheat. Personally, I would not use an organic based rod XX10 on any thing of medium carbon content.

By okwelder82 (***)

Date 12-14-2008 03:07

I got called out to rig one night because they hung the pipe while drilling, so I had to cut the pipe off at the floor and cut the tool end off and reweld it to the piece on the floor. The pusher said " put a good root bead in there"........ in my head Im thinking thats easy for you to say.

By 803056

Date 12-14-2008 16:42

If the pipe is magnetized, as suggested by several of you gentlemen, demagnetize it as detailed in the following post: http://www.aws.org/cgi-bin/mwf/topic_show.pl?pid=122048;hl=demagnetizing

As for welding the high alloy steels, always use a low hydrogen with high preheat. Typical preheat temperatures for the 41XX steels are on the order of 300 to 500 degrees F. The thicker the base metal the higher the preheat temperatures.

The low hydrogen electrodes will only meet the low hydrogen requirements if it is properly stored in an electric holding oven or if it comes out of a "tin" of fresh electrode. Electrode stored overnight in an unplugged oven allows the electrode to absorb moisture from the environment (unless you are where the temperature is -40 degrees or so).

I've had cases where the oven was unplugged overnight and plugged in first thing in the morning. After about a half hour of heating, the top of the electrode oven was opened only to see the condensed water collecting on the colder steel cover. Throw the rod away, because it is no longer "low hydrogen"!

Best regards - Al