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View Full Version : CWB, Stick, 7018, Pipe welding questions, ty in advance



then3wguy
12-31-2009, 12:01 AM
I was wondering if anyone has had experience with a CWB (mild steel) Smaw pipe test

If so, you you explain what you do?
- how many root stop/starts (4? one for each position bend test?)

- root welded with 7018 also?

- once roots welded, do you just fill up the whole pipe with weld or are there also start/stops for them

- When do you usually use the grinder? (other then when mistake is made) ex: would u use the grinder to feather back the start/stops to get good fusion?

- do you grind a Land on the bevels of the pipe or keep them beveled (or is it by choice)

- Is there a Maximum/minimum amount of cap passes to be put on

- Only stringers? or can a little weaving be used on verticals

Any information would be greatly appreciated

Thanks in Advance

then3wguy
12-31-2009, 02:21 AM
actually i found a pretty good download-able book

but any input is appreciated

gto_welder01
12-31-2009, 03:09 PM
all the pipe test i have done are 6010 root and hot pass (1st and second pass), then 7018 fill and cap. i usually use a nickle land and a 3/32 gap. on the root pass i grind all my starts and stops. once im dont welding out the root i like to take the grinder and grind off all the slag that is left from the 6010. then i turn up the machine a little bit and run the hot pass. once the hot pass is in i like to take the grinder and give it a little grind again, most of the time i just use a wirewheel on this pass. then i start to run stringers for the fill and cap.,.,,,,,,,,, on pipe that runs horizontal and you weld vertical, you can also weave your passes.

Jonnyrod
12-31-2009, 07:51 PM
all the pipe test i have done are 6010 root and hot pass (1st and second pass), then 7018 fill and cap. i usually use a nickle land and a 3/32 gap. on the root pass i grind all my starts and stops. once im dont welding out the root i like to take the grinder and grind off all the slag that is left from the 6010. then i turn up the machine a little bit and run the hot pass. once the hot pass is in i like to take the grinder and give it a little grind again, most of the time i just use a wirewheel on this pass. then i start to run stringers for the fill and cap.,.,,,,,,,,, on pipe that runs horizontal and you weld vertical, you can also weave your passes.

+1 here. I run a 6010 root with the tacks ground thin and tapered. On the hot pass drag the rod over the tack to help preheat and consume the tack. For x-ray I run the machine up about 5 to10 amps for the hot pass. Grind the root and hot pass clean till no wagon wheels and start to fill with the lo-Hy with the same setting on the machine. A single or multi-bead cap is dependant on what schedule piepe it is and or weld specs. You will always have a better tie in by dragging the rod over your start point to aid in preheating and is better than a striker plate for carbon and stainless. With practice this will clean up your tie ins so they can't even be seen with a glow ball. ;)

snoeproe
01-01-2010, 12:09 AM
I'm guessing your in Canada since your referring to the CWB.
The CWB (Canadian Welding Bureau) weld test/certification is for structural plate.
The TSSA (Technical Standards and Safety Authority) is the agency you do pipe test/certification with in Canada.
I've never been CWB certified but I do hold pipe tickets through the TSSA. The black iron pipe test your referring to I believe is the ASME P2 test. It is a 6010 root with 7018 low hy fill and cap, usually welded in 6G position. I always grind down my 2 6010 passes. I like to use 3 tacks. Always grind down your tacks and feather the edges too. That will make tie in much more easy. Then all the 7018 passes are cleaned with a wire wheel. You can use any root gap and land thickness you wish. For me, correct land thickness is critical when welding root beads with 6010 5P+. I want a strong 3/32 land and a strong 3/32 root gap for 3/32 rod. I test with 1.5" sch 160 pipe. I believe it's about 7 passes for me to fill it with 3/32 rod. I end up capping it with 3 stringer beads but if you want to weave your fill and cap, you can do that too. It's what ever works for you.
Your finished piece will be required to pass 4 bend tests, 2 root and 2 face bends after grinding off your cap and cutting the pipe. Your allowed 1/8" of a crack to open up on your bend samples. Anything more than that will result in failure. The inspector will also do visual inspections of your root when it's completed and your final cap.

snoeproe
01-01-2010, 01:17 PM
Correction:
I just dug out my tickets.
This test is the ASME or S P-1, not P-2.

then3wguy
01-02-2010, 07:07 AM
thanks for the information

Much appreciated