cold wire tig?

By SWP

Date 10-31-2007 17:24

Can the pipe be rotated or must it be welded in a fixed position?

By alumtig (**)

Date 11-01-2007 11:06

yes, these are short sections of pipe with an 8in. WNRF flange on one end and an 8x3 conc. red. and a 3in WNRF flange on the other. All can be chucked up in a positioner and rotated. I am currently looking at a cold wire tig that I have in house. I have set it up with a fixture to position the gun above the pipe and have bypassed the trigger and set that up with a toggle switch. I spoke to tech services from the manufacturer of this unit yesterday. The gentleman was very helpful and is sending a care package which he sent UPS overnight. We talked about parameters and deposition rates which I really need at this point. Hopefully this "care Package" will contain the information that I need. The biggest issue that I have with this unit is increasing the weld size and the wire feeding into the weld puddle smoothly. I still have filler metal bottoming out in the weld puddle which then causes the gun to move. I need to know what the machine is capable of producing as far as weld size and what travel speed can be expected. Currently I'm using an .045 wire and getting approx. a 5/16 in. bead. I am greedy I want a larger bead with a higher travel speed to minimize weld time per joint. Of course all of these joints RT so it has to be welded with that in mind.

By DaveBoyer (*****)

Date 11-02-2007 03:28

I am curious about the setup You have. There is a unit on eBay that looks like a spool gun with a TIG torch mounted beside the nozle. Is Yours something like this?

By alumtig (**)

Date 11-02-2007 16:24

Hi Dave,

Look on the internet for CK Worldwide Inc. they have a very good website and included are pics of the unit I have which is a WF-1

Tracy

By DaveBoyer (*****)

Date 11-03-2007 03:37

Thanks

By webbcity (***)

Date 11-01-2007 04:25

tracy , i'm going to e-mail you some web pages if i can find them it may help you . i have some hard copy info. if i can find it . good luck . willie

By alumtig (**)

Date 11-02-2007 16:26

Willie,

I did get the e-mails and the links thanks soooo much for the info. I think that I can get by with the system that I'm currently using but always needing new info.

thanks again,
Tracy

By medicinehawk01 (**)

Date 11-01-2007 14:18

Tracy,
Dimetrics makes such a machine you are looking for. I don't know who to contact (other than Dimetrics), but a couple of years ago my employer looked into getting one. It welds from root to cap completely with this unit and, if it is a specific diameter you will be welding, than it might be feasable to rent one.
While we did not end up renting/buying the GTAW orbital wire feeding welder, I got to run it for a week or so on some carbon & stainless pipe. It does a flawless weld, but you need a skilled person to operate it because the controls you have to monitor require someone who knows alot about welding in order to make the right adjustments. Also, you'll need a facing machine which put a "L" bevel on the pipe as the joint is configured so that you'll get a awesome root pass with the pipes being butt up tight with no gap. You have to see it to understand what I am talking about, but like I mentioned, when the thing runs right.......I have never seen a better looking weld.
My employer decided not to get it because we change diameters so often and because of the skill level required to use it, because like I said, they will have to able to know what parameters need adjusting to make the right ones.

By js55

Date 11-01-2007 16:52

If its all roll out stuff I wouldn't mess with orbital. A machine GTAW with either cold or hot wire feed (cold would be my recommendation) with AVC (automatic voltage control) would be ideal. To reduce weld time isn't a matter of piling on filler but closing the gap. With AVC you can run a closed butt V with the wire feed to essentially give you a root hot and first filler in one. You can google for manufacturers.
You haven't mentioned the material yet that I've noticed.
Limiting you to GTAW seems a bit unreasonable unless its some extreme application (not sure what that would be). Even cryo is done with alternative processes these days. Make sure you price accordingly. Don't price for FCAW and give them GTAW.

By swsweld (****)

Date 11-02-2007 02:24

Dimetrics Liburdi, Magnatech, Arc Machine, Astro Arc all make machines that will do the job. You can rent or buy. If it is all sch. 40 you can use a K ring or E B ring for the root pass without changing the bevel degree or joint config. Using a consumable insert makes the root pass much easier, you can pull the ring with or without adding wire. Adding wire on root will fill joint quicker and insure that you do not reconsume the root pass while welding the hot pass. Open butt will take an experienced operator. If you roll the pipe and weld 1G you can greatly increase production. With the right parameters and operator you can weld nonstop from root to cap in 3 or 4 passes. Not recommended with inexperienced operators. Too many things to look at. You can still make good production without rotating the pipe but doubt it will offset the expense of machine welding on sch. 40 pipe. You will get high qualty welds. The track set up is something to seriously look at if you go with machine welding. Not so much the cost if only welding 8", but the time to set it. I think Magnatech utilizes a chain system with rollers on the carriage that would be quicker than a hard aluminum track. They all have steering capabilities. But if you weld 1G you can mount the weld head on the half track and roll the pipe. I've been away from the machines a few years so a call to the sales rep may be worth while as they may have better more current info.

By js55

Date 11-02-2007 13:40

My opinion is those machines are not the proper application for roll out 1G circumferential pipe welds. I think you will find they are prohibitively expensive and not near as productive. They are excellent machines and invaluable for their applications, but the set up time involved in each weld is far in excess of the single set up time involved in finding a cold wire GTAW (with AVC even-which, though not necessary has distinct advantages) with a single set up on what I am assuming is an already existing manipulator head (which could if necessary be rented for far less than an orbital). Just pop off the SAW and mount the GTAW (or add an attachment that allows both depending on the size of your manipulator). And you do it once. Not to mention that fit up tolerances are much tighter for orbitals, which adds to your fit up time.
And how many units are you going to rent or buy?
In most pipe fab operations the amount of roll outs is about 85% to 90% of the welds (if not I'd fire some spoolers). Even better if you have good spoolers.
Consumable inserts are a good option in some circumstances but keep in mind they also increase the volume of weld metal necessary by a considerable amount (not to mention the skill involved in recognizing the 'collapse'-even if you're establishing machine parameters), not only adding to the expense of the inserts themselves (they ain't cheap relatively) but the subsequent filler metal as well.

By js55

Date 11-02-2007 13:50

As an addenda: you have a flange, pipe, reducer, and a flange. Essentially 3 welds of two different sizes all lined up. With a GTAW on a manipulator head you can just slide the manipulator on the angle iron track and start right in on the next weld. No change in set up. Not true with orbital where a tracking change would be necessary.
You can even, if you wanna really be creative and productive, hot bolt as many pieces as you can together and center up on the large welds first in your positioner, doing all of the large welds first, and then center up on the small welds doing all of those. Conceivably doing as many as 15, 20 or more welds (taking the weight off of you rpositioner witha roller stand-limited only by the size of your work station and your manipulator track)without a single change other than sliding your manipulator along its track. And a single purge if its alloy.

By alumtig (**)

Date 11-02-2007 16:23

Hi,
Things here are looking up. I recieved a care package yesterday from CK Wordwide Inc. the manufacturer of the cold wire tig that I had in house. Included were 2 different size liners along with a larger size drive roll several different tips and an adapter to alter the position the wire was feeding into the puddle. I changed changed everything over and used an .052 wire dia. Bumped my amps up to 305 and travel to approx. 10 in. per minute. Forgot to mention that this is all just carbon steel nothing exotic. My only problem now is that I'm using a 350 amp power source with a 40% duty cycle so we are having to let it cool down every couple of passes otherwise the unit shuts down. Otherwise the welds are looking good and the production rate has increased. Am setting up some RT for Mon. and am hoping that everything remains good.I really like the idea of bolting the units together and will most likely do that. Seems like it would save some set up time.

Tracy

By js55

Date 11-02-2007 16:41

I'm sure you're on top of it, but make sure you have clean flange faces so as not to allow any arcing from assembly to assembly.