i want to learn to weld...

[DValentine]

Jeremy that is a cool site. Bookmarked that one. I agree about having to switch leads. Sometimes if we have enough machines we will have one for stick, and one for tig. But remember we are not moving far. The tubes are very close together. On a typical outage working on a 350 to 750 megawatt boiler there are 250 -300 boilermakers on site. Thats days and nights included. Half of those are welding tubes, the others are working on rigging parts in, or welding plate in duct work or the like. Sometimes its hard to get a welder... . there are fights over leads and such. We used to grind our own tungsten, but now the contractor buys it sharpened. The tool room man touches them up on a bench grinder or a Piranha II. They are neat, with a diamond wheel. Greg makes a good point about 2%.

GiesJ- Yeah, we are governed by ASME and AWS. But what has changed since I got in was that the heavy wedding band created cavitation on steam tubing.
I am far from an expert on this subject. Just passing on what I have learned.

Dave

 

[JWelch]

That must be noce to have access to a Pirahna. Got to use one of those once and it was sweet. It seems like every job I am on there is a fight over leads. One their tools boys made the mistake of telling me they got like 10 rolls of number 2 in. So I took a walk down there and made myself 200 feet each of leads. They stayed in my personal box until the let me go.



Greg that is weird I have always been told and seen a precise sharp point on my tungsten. But if I do end up dipping it I stop and grind a little to prevent it from showing up hopefully.

 

[GHarman]

JWelch, In my experience, and proven in a prototype through production environment, a needle point actually spreads the arc whereas a blunt tip actually concentrates the arc. This was proven on one project that was welded entirely with a 1/8" tungsten, 2% Thoriated that was finished ground cylindrical! Course, this was under laboratory conditions. If you have time to experiment? Try a few different point geometries in similar conditions. It may suprise you. It may be one reason for your increased amperage requirement to obtain the expected penetration? However, be aware that in a field welding environment, you may be more concerned with the possibility of High Density inclusions in your weldment. Those sharp points do blow off. Hope this is helpful. GregH

 

[JWelch]

Well, I have threetest that I am going to be taking on Thursday. A 2" XH wall HeliArc all the way out, 4" HW 6010/7018, and a Sch 80 SS HeliArc. This is to get on a job to rebuild that BP refinery in La Porte, Tx.

 

[DValentine]

Good luck man... . don't stick it.

Do you get to use a grinder when testing or just a hand file?

D

 

[GHarman]

Well, I have threetest that I am going to be taking on Thursday. A 2" XH wall HeliArc all the way out, 4" HW 6010/7018, and a Sch 80 SS HeliArc. This is to get on a job to rebuild that BP refinery in La Porte, Tx.

JWelch, Eat a good Breakfast, take some B-Vitamins and take your time . Hope you do WELL! GregH

 

[GHarman]

JWelch

How did your welding test go? GregH

 

[JWelch]

Waiting for the xrays to come back. The SS turned out to be SCH160 not 80 like I was told. Plus the cwi only wanted 2 tack 12 and 6 o'clock. Never had to do that before. Plus I won't know I can go on the jobsite for 3 to 4 days next week with the physical and drug tests(2). One was urine and the other was hair. Now I have a huge bald spot on my left arm.

 

[GHarman]

JWelch

How long of a tack would he let you have? Did you sequence your root so the one side did not close up completely, or did you gap it wider on one side than the other? Did you run a hotpass? GregH

 

[DValentine]

Yeah, 12 and 6 seems funny.

 

[JWelch]

The two tacks for 1/2" long. Yeah I ran a hot pass that was before they would look at the root. I guess they did not want stop the purge before those two were done. One side was a little wider than the other. It helped and straightened out I guess cause I was going pretty fast. What ****** me off the most was that first I was told that the remotes worked in the booth I was in. Well I found that it did not work while I was doing my tacks and had to cut one out completely. Then had to adjust my amperage at the machine everytime. That got really annoying. I also was asking them how their machines acted ya know like do they burn a little hotter than they are showing? They told me they could not tell what bs I was thinking. I have never not been told if asked about the machines in a weld test lab. The last too went fine. Behaved a lot better after I figured out the remote did not work. Plus all my bevels were a lot shallower than I thought they needed to be less than 35* s.



Thanks for all of the wished for good luck.

 

[GHarman]

JWelch, You just experienced one of the dirtiest tricks played on a Weldor. My SWAG is that the remote control contact plug ins were pulled out of their recepticle(s) in the power supply just far enough to allow for on/off operation, but the rheostat fine amperage control is eliminated. This trick was played on me at Sundstrand Hydraulics back in 1995. They wanted Weldors, but only their buddies. They told me that the test was Stainless Steel, but I had to dig my coupons out of the Carbon Steel Scrap bin. The rod was 1/16" 308L, I was "allowed" a purge but they told me the foot control did not work properly. (At least they told me). I wasn't satisfied with their explaination, so I did a little troubleshooting. Found all the adjustments were purposely set contraindicated to what I wanted/needed to do and the remote plugins were at the proper location but were not engaged into their recepticles all the way. It was an obvious sabotoge. I did pass the test, but they hired their buddy instead. He lasted 3 weeks. I found out what was going on 'cause the man who was my supervisor on the test was a student of mine 7 years prior. My point in all this is check your powersupply thoroughly before you start. GregH

 

[DValentine]

Here is a link to flux cored tig wire. Glad you passed. Sorry they messed with you.

http://www.kobelco.co.jp/english/welding/files/v4n2,5-6.pdf

 

[JWelch]

Dave,



I passed visual I don't know about the xrays yet. I have heard of shops that will put stuff inside of the test coupon so that a problem shows up on film. I have only heard that though. Of course I am not real happy about not being there when it gets tested and then get to look at the film(s) or bend(s). Been there all they would say is that I failed but couldn't give me any details which always ****** me off.

 

[JWelch]

Dave, that is pretty cool stuff. Never heard of it before. You ever use it? The only issue I see is that root pass they show it looks like it is completely sucked back.

 

[DValentine]

Yeah, I have used it. Although I have not done a lot of Stainless tubes, and no pipe. It is easier than the purge.

 

[JWelch]

This company contacted me and asked if I was a HiBay welder. What is this or is something they made up.

 

[GHarman]

HiBay Weldor!

Your gonna have to ask them! I worked in a shop that had a High Bay. They had an overhead crane for pulling Rail Car lids and lifting and repositioning large and heavy objects. It could mean a set of tubes that are several stories tall? GregH

 

[JWelch]

Oh cool thanks for the explaination.

 

[DValentine]

Never heard of a hibay welder... . but Y'all Texans talk a little different.

LOL

D