It is currently Thu Apr 27, 2017 10:45 am Advanced search

Preventing Distortion on Flat Plate

General welding questions that dont fit in TIG, MIG, Stick, or Certification etc.

Preventing Distortion on Flat Plate

Postby cjarnutowski » Wed Apr 19, 2017 11:58 am

Hi guys, thanks for having me.

I tried to search for this but its pretty difficult to form a query for this specific question.

I am welding a 3"x.25" round tube to a 24"x24"x.25" plate, dead center. The material is steel and the process is TIG. I was hoping to hear some of your tricks for preventing the plate from "cupping" up toward the post on the side of the weld.

Any wisdom is appreciated,

Thanks,
Chris
cjarnutowski
New Member
 
Posts: 2
Joined: Wed Apr 19, 2017 11:52 am

Re: Preventing Distortion on Flat Plate

Postby exnailpounder » Thu Apr 20, 2017 6:17 am

Welcome to the forum! Plate is the worst offender for distortion. I have had some success with tacking a couple pieces of angle on the non-weld side, clamping the piece down, doing the weld and then breaking the tacks and grinding them off. This isn't always possible but it helps.
Ifyoucantellmewhatthissaysiwillbuyyouabeer.
exnailpounder
Weldmonger
 
Posts: 2246
Joined: Thu Dec 25, 2014 9:25 am
Location: near Chicago

Re: Preventing Distortion on Flat Plate

Postby Farmwelding » Thu Apr 20, 2017 6:21 am

Depending on the use of the part, you could take another thick plate and tack it to the base plate on this. If you need an example, Jody has a video about mig welding aluminum that demonstrates this with aluminum plate
A student now but really want to weld everyday. Want to learn everything about everything.
warning!! Bad English may be in post. It's off a phone/autocorrect. I've had teachers with worse spelling!
Instagram: @farmwelding
Nick
Farmwelding
Weldmonger
 
Posts: 906
Joined: Thu Mar 10, 2016 11:37 pm
Location: Wisconsin

Re: Preventing Distortion on Flat Plate

Postby motox » Thu Apr 20, 2017 6:24 am

presetting can help as well. you will have to try a couple of pieces
to see how much set to put into the flat piece to end up with a near
flat finished surface.
craig
htp invertig 221
syncrowave 250
miller 140 mig
hypertherm plasma
morse 14 metal devil
motox
Weldmonger
 
Posts: 1231
Joined: Thu Nov 28, 2013 12:49 pm
Location: Milford Delaware

Re: Preventing Distortion on Flat Plate

Postby Mike » Thu Apr 20, 2017 6:51 am

Chris, welcome to the forum.
M J Mauer Andover, Ohio

Linoln A/C 225
Everlast PA 200
Mike
Weldmonger
 
Posts: 1786
Joined: Mon Dec 06, 2010 1:09 pm
Location: Andover, Ohio

Re: Preventing Distortion on Flat Plate

Postby Poland308 » Thu Apr 20, 2017 7:29 am

Leave a gap between the plate and the tube when you tack them togeather. Gives a little relief from shrinkage as you weld it.
I have more questions than answers

Josh
Poland308
Weldmonger
 
Posts: 1802
Joined: Thu Sep 10, 2015 8:45 pm
Location: Iowa

Re: Preventing Distortion on Flat Plate

Postby AKmud » Thu Apr 20, 2017 10:53 am

Clamp the plate solidly to a table or a strongback of some sort if you can, and don't un-clamp it until it has cooled completely.
AKmud
Guide
 
Posts: 144
Joined: Fri Jan 25, 2013 1:47 am
Location: Wasilla, Alaska

Re: Preventing Distortion on Flat Plate

Postby Arclight Ironworks » Thu Apr 20, 2017 10:55 am

cjarnutowski wrote:....I am welding a 3"x.25" round tube to a 24"x24"x.25" plate, dead center. The material is steel and the process is TIG. I was hoping to hear some of your tricks for preventing the plate from "cupping" up toward the post on the side of the weld...


What can you tell use about the intended use of this welded item? Static, dynamic, cyclical loading? Access to oxy-propane or oxy-acet torch?

Option #1. Micro tack the 1/4in round tube to the surface of the 1/4in assembly plate. 4ea 1/2" long tacks at cardinal positions on the clock. Cut 2ea 3/32" TIG filler wires into 24" lengths. Set aside. If available, sever another section of 2ft x 2ft x 1/4in steel plate as fixturing for your 1/4in assembly plate.

Stack up, from bottom to top. 1/4in fixture plate + 3/32" TIG filler at third-points on the surface of the 1/4in fixture plate + 1/4in assembly plate. Clamp the fixture plate to the assembly plate, bi-diretionally. This sandwiched arrangement "preloads" the system and introduces a micro-camber. Note, a fixturing plate is not req'd and you can easily camber the assembly plate directly to your welding table.

Weld the unit in quarters (e.g. 12 to 3 o'clock, then 6 to 9, then 6 to 3, and finally 12 to 9). Allow unit to cool, completely. Unclamp the assembly plate from the fixturing plate (or weld table). Inspect and FlameStraightening, as required, via oxygen-pro/acet torch by applying heat to the BOTTOM of the 1/4in plate.

Option #2. Disregard the 1/4in fixture plate approach. PreHeat the tube and entire assembly plate to 150F. Tack, followed by weldout a la the above technique. Allow the unit to cool. Inspect and FlameStraighten.

Unsure if you are experienced with oxy-fuel and FlameStraightening. We could walk you through the baseline technique if you have access to the equipment.

Understand that you cannot PREVENT heat from doing it's thing. Ever. Even placing a Battleship or M1 Abrams Tanks on the system as fixturing will not prevent warping. Minimize, yes. Eliminate, no. Atoms within the Elements are of star dust. Strong and Agile like the HoneyBadger.

Approach heat as a "tool". Apply to your advantage to affect the geometry during weldout and minimize distortion. In this situation, TIME between welds and attack approach are your allies.
Purpose, then passion; practitionership, then proficiency. Process and patience, talent and hard work. That's the discipline.
User avatar
Arclight Ironworks
New Member
 
Posts: 4
Joined: Tue Apr 11, 2017 10:31 pm

Re: Preventing Distortion on Flat Plate

Postby WildWestWelder » Thu Apr 20, 2017 11:13 am

The first question I have is how much cupping are you willing to put up with. Second, what material is the 1/4" plate? Is it cold finished? If it is then good luck, never had any luck with that. If it is hot rolled (A36) you shouldn't experience very much cupping unless you need it absolute flat.
WildWestWelder
Active Member
 
Posts: 44
Joined: Mon Apr 03, 2017 7:43 pm

Re: Preventing Distortion on Flat Plate

Postby PeteM » Thu Apr 20, 2017 11:26 am

I'd place the plate on the table, the frame on the plate, and clamp them together. Then place/clamp some aluminum angles inside the frame on the plate to sink the heat. Let the square tube take most of the heat.

Anything beyond that begs the question "How important is it?"
PeteM
Ace
 
Posts: 210
Joined: Sat Dec 03, 2016 11:28 am
Location: Pittsburgh

Next

Return to Welding Forum General Shop Talk