1 inch and over

[dyn88]

My regional ABCO representative came by my shop yesterday to help us gear up to weld some one and a half A36 and two inch A36.He told me of a wire with silicon and metal fragments in the core(like dual sheild). He claims that with this wire there is no preheat neccassary. Ive always been told and practiced the one inch and over rule. If your base is one inch or thicker you must preheat to avoid eccessive warping and any cracking. Is anybody familiar with this miracle wire, or should I call his boss and ask him if I had been led up a tree with no branches?

[hankj]

I can't find any reference in any matalurgical text I have that supports welding thick sections without pre-heat. We'll see what the senior statesmen on the board have to say about it, but I just can't imagine that the thermal shock that would occur in the base metal from sufficient heat input to achive a good weld would not have an adverse effect.

Hank

[Rocky D]

He was speaking of Metal-cored wire....there's several types for heavy operations like you suggest. I have always used either short arc or spray arc with ER70S-6. I was on a project where one of the certifications was a 1" A36 vertical. .045" wire 50/50 CO2/Argon. Yeah it warped real good, but I had it figgered out so that with a pre-bend, it came out flat. No pre-heat.

Here's another job I did with no pre-heat....2" to 5 1/2" HRS. 1/16" ER70S-6 and 98/2 gas.

[hankj]

Rocky,

How in **** does one pre-bend anything 1" thick without heat? Man I AIN'T messin' w' you!

Hank

[Rocky D]

Sorry, I wasn't clear...this was for a cert...2, 1"x4"x8" plates bent away from you about 5° or more and when done it pulls itself flat. If you were to weld them flat to begin with...it would pull into a "V". Not acceptable for a cert that they have to cut and bend. The plates I ran were secured with 4 clamps made especially thick for this, too. When the molecules shrink there is NOTHING that will stop it. So you have to plan ahead.

On the heavy weldment I did there was no preheat. When I finished the fillet on the 5 1/2" plate it moved 1/8" ! On that weldment the engineer built into it a 1/2" ± tolerance in it for shrinkage. I was amazed to see a 5 1/2" plate move that much!

[Joseph]

Rocky D,

May I ask what is the item You made?

Thank You

[dyn88]

Rocky that is some big [email protected]#t and it looks real nice. Did the large plates with the 1/16 get magged afterwards? The plates I have to do will be magged. also did you bevel the joints on the fillets? Mine have to be 75% penetration.Finally was 1/16 a solid wire, and with 98/2 Im guessing you sprayed. Just so you know Im gonna try to pulse spray and judging by the looks of your work I may not need to preheat. Any advise you may offer would be greatly appreciated.

[Rocky D]

Rocky that is some big [email protected]#t and it looks real nice. Did the large plates with the 1/16 get magged afterwards? The plates I have to do will be magged. also did you bevel the joints on the fillets? Mine have to be 75% penetration.Finally was 1/16 a solid wire, and with 98/2 Im guessing you sprayed. Just so you know Im gonna try to pulse spray and judging by the looks of your work I may not need to preheat. Any advise you may offer would be greatly appreciated.

This part was for a 125 ton stretch bender. You can see more pictures here: http://img78.photobucket.com/albums/...etch%20Bender/ I needed to get at least 85% penetration, or more, so I chamfered the 2" plates to a 1/2" land. 325 amps at 28 volts using a Miller (of course) CP300, and 52S wire feeder. The insert you see here is 4" and I started our with 1/4" 7018, but the arc blow was horrible. I did manage to get the majority of it done with stick, but the M-40 Miller gun was my weapon of choice.
It wasn't magged, just stress relieved and sandblasted in Los Angeles. We couldn't tie up one of our heat treat ovens that long, so we out-sourced it. I think weight was another issue...it weighed 7 tons. I don't know why you need to pulse spray, unless it is out of position....I was able to turn this puppy so that all my fillets were either horizontal or at a 45° in the positioner I built.
Any time you build something this thick, that will be machined after, design it with a tolerance that will allow for warpage...it's tooo difficult to try to keep something like this to too close a tolerance.

[dyn88]

unfortunately the engineers at IAE(some aircraft engine manufacturer related to pratt)call out 2 plates 1 1/2 with a 3/4 honey comb in between. The 1 1/2 is a finished dimension so we are using 1 3/4 amd gonna put it in the bore mill and get a nominal after normalization. Thanks for the help.

[Blown S-10]

its that something that size/weight would warp.

[HAWK]

Blown-S10,

The fact the 5.5" weldment pulled .125" is amazing! It is not nearly as amazing to me that it pulled as the amount of heat required to create the warpage. Spray inputs an awesome amount of heat in a very short time. I feel sure the warpage would have been considerably worse with short arc.

[Blown S-10]

ok, i gotta ask, don't want to assume, you know. are you guys talking about the 2 pieces to be welded warping out of angle ? or the pieces warping out of flatness ?

[Bulldog]

Rocky,
GREAT job! AWESOME! JUST AWESOME!

[dyn88]

warping out of flatness( its crazy huh)

[Blown S-10]

crazy isn't the word for it . nice work man