Continious welds 3" O.C.

[joela36]

I have a embed plate for a concrete wall that is 3/8"x7'X 44' A36. A callout is made for a 3/16 facing weld 3"o.c. vertically the entire length of the plate. Is there a automatic process I can use that won't distort the plate should I decide to weld it before it is installed? In this case I would be welding it flat. Thats 1,232 feet of weld. No call out has been made as to what the filler material will be.

 

[hokie66]

I can't get the picture. Your plate is 7 ft x 44 ft? How are welds which are 3" on centre also continuous? Where does the 1232 ft come from?

 

[connectegr]

Alternating 3" - 3/16 fillet welds should not create much heat or distortion. A detail would help identify any potential problems. This can be automated, but depends on your equipment. For A36 plate the wire/electrode should be 70ksi. But the actual filler/shielding will depend on your equipment and preferred welding process.

http://www.FerrellEngineering.com

 

[msquared48]

Hokie:

44 X 7 X 2 X 2 = 1232

Should be (44 + 7)2 - the perimeter - then that doubled for another pass equaling 204 feet of weld at 3/8"

At least that's my take on it.

However, I cannot answer the question regarding the continuous intermittent weld. The concept baffles me.

Mike McCann
MMC Engineering

 

[Ron]

I'm confused. What is being welded to what?

 

[ToadJones]

44'x12" = 528" wide plate

A vertical weld is made ??decoratively?? every three inches????

528"/3" = 176 vertical welds that are each 7 ft long

176 x 7ft = 1232 ft of weld!

what the hell is a facing weld?

 

[ToadJones]

...do i smell an architect in the area?

 

[hokie66]

Mike and Toad,
Ron and I are already confused enough without your dodgy arithmetic. Perhaps the OP will eventually enlighten us.

 

[joela36]

I think connectegr has figured it out. To answer all thoughts I will calify the situation. A facing weld would be similar to hard facing a plate with additional welds to prevent wear.Some people refer to this as cladding. You will see this alot on heavy equipment or in the mining industry where steel plates tend to wear faster due to the abrasive nature of sand and gravel. The designer is asking for a 3/16 weld that runs vertically on the plate, the plate being 7' in height.If you divide 3" on center the entire length of the plate in 44' that would be 176 -7' vertical welds.Hope this clarifys any thoughts.

 

[stanweld]

joela36,
Are you welding (fillet and plug welds) an abrasive resistant material like AR400 to the A36 base plate? Or are you localized hard face overlaying the A36 material? What is the hard facing material?

For minimizing distortion, pulsed transfer gas metal arc welding is recommended with vertical down progression.

 

[ToadJones]

seems as though my dodgy arithmetic was spot on

 

[Tmoose]

I'd expect all the weld material contracting on one face of the plate will try very hard to curl up as it cools down. The tendency will be there whether restrained by the undefined installation, or not. A 44 foot long piece of 3/8 inch steel will be pretty flexible and wiggly, relatively speaking.

Flatness tolerance for brand new 3/8 inch plate is not likely to be better than 1/2 inch in any 10 foot length, even before it gets tweaked trying to rig it off the truck.

Will the installation consist of a multiplicity of fasteners pulling it hard against a rugged flat surface?

 

[hokie66]

Toad,
I humbly apologise. But not to Mike, and I don't think connectegr had it figured, either.

 

[Ron]

Hell, I'm still confused. Hardfacing is typically done over an entire surface, not in 3" increments. I've done hardfacing, abrasion mitigation, flame spray, etc.....but not in strips. Enlighten me, please.

 

[connectegr]

Since Hokie blew my cover, I admit I did not expect welded strips. I thought the edge was to be welded along the perimeter. I guess my initial response would still apply. But the plate edges should probably be restrained before welding the strips. Weld shrinkage over a 7' length might cause deformation of a 3/8 plate. Welding shorter lengths and allowing incremental cooling might minimize the shrinkage. This can also be automated, but may not be economical for a small number of applications. Lincoln Electric can provide a lot of support if this will be a repeated process.

http://www.FerrellEngineering.com

 

[ToadJones]

hokie-
Don't apologize. I was kidding.
I intended to throw a smiley face in there at he end, but I was in a hurry.

I'd say use a 5/8 plate. That will give you 1/4" "wearing surface" and will be a lot cheaper than welding the hell out of your 3/8 plate.