Custom Made Heavy Beam Question

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I work for a small company of around 50 employees & we just got a job to make some heavy beams because, I guess, that common beams won't work for this application. Anyway, we have to make 11 beams using 1-1/2" x 9" flat bar for the flanges & 3/4" x 4" flat bar ripped down to 3-3/8" wide for the web. The flat bar for the web also has to be beveled on each edge & each side & the beams will be 21 feet long & welded out with sub arc. These idiots I work for think we can rip the 3/4" FB for the web to get the 3-3/8" width & do all the beveling with a track torch & don't realize how much distortion & warpage all this heat will cause. I suggested they look into one of those hand held electric milling machines for bevelling plate & they've never heard of one. Anybody care to say how YOU would go about this job & what equipment would be needed etc.? I think this time they've bitten off more than they can chew.
Reply:I would agree with you.  The hand-held milling machines are a much better alternative, and they cut quite fast.  They are not cheap.  The one's I've seen are $5k-$6k.  But you'll get a perfect bevel, which will make the sub arc a lot easier(or any welding for that matter.Cutting the web of those custom beams to 3 3/8" is going to be a mess no matter how you tackle the job.  A plasma cutter might make the cut faster with lower overall heat input, but you're still going to get distortion.  Were I running the show, I'd try and order the material sawn to 3 1/2" or 3 5/8", and then bevel down to the finished width.  If the tolerances on the beam dimensions are tight, someone's going to have to do some homework to figure out the cut losses, and gains in width from joint geometry.If you're double beveling each side of the web, you might not have to remove much material from the 4" plate at all.  By the time you bevel both sides, and put some kind of land on the bevels, you may be really close to 3 3/8" final width.  Something to consider.I hope there's money in the petty cash box where you work to cover the extras you'll need to finish this job...Benson's Mobile Welding - Dayton, OH metro area - AWS Certified Welding Inspector
Reply:[QUOTE=A_DAB_will_do;530142]I If you're double beveling each side of the web, you might not have to remove much material from the 4" plate at all.  By the time you bevel both sides, and put some kind of land on the bevels, you may be really close to 3 3/8" final width.  Something to consider.I think you're onto something here & at least some of the bevellers I looked at on the web will also cut at 0 degrees so the width could be obtained by milling the landings & thus no heat at all. I know the machines are expensive but sometimes you have to spend money to make money. There's a German made brand named Trumpf that looks bad *** at least from the demo video I saw. But, assuming the beams were fit up without a hitch, I can only imagine what the heat from welding them out is gonna do. I don't know, i've never been around sub arc. Anyway, I appreciate your input.
Reply:Strip the plate from plate and bevel at the same time some value added warehouses will do this for you ie Chapel steel ??  you can put multiple torches on a buggy and do it , do not use bar /UM plate its a waste of money .
Reply:Cutting from plate sounds like a good plan, except that my local distributor does not carry plate over 20 feet long, and the beam is to be 21 feet long.Oftentimes bar stock is available in lengths over 20 feet.Your mileage may differ, check with your steel supplier.RichardSculptures in copper and other metalshttp://www.fergusonsculpture.comSyncrowave 200 Millermatic 211Readywelder spoolgunHypertherm 600 plasma cutterThermal Arc GMS300 Victor OA torchHomemade Blacksmith propane forge
Reply:I would contact Hypertherm to see if there's a trolly system available that would mate up with their 85 Cutter.A motorized trolly (to set cut speed) would be ideal.  One pass to cut the flat bar to size.  Second pass to cut the bevel.  Flip.  Cut bevel on backside.Syncro 250 DX Dynasty 200 DXMM 251 w/30A SG XMT 304 w/714 Feeder & Optima PulserHH187Dialarc 250 AC/DCHypertherm PM 1250Smith, Harris, Victor O/ASmith and Thermco Gas MixersAccess to a full fab shop with CNC Plasma, Water Jet, etc.
Reply:Do I have the profile of this beam correct? If so, the first thing I would do is ask the engineer why he design such a stupid looking beam. Second, what about using 3" flat bar and filling the gap? Wouldn't that be less work than cutting down the 4"? Attached ImagesIan TannerKawasaki KX450 and many other fine tools
Reply:Cut from a 96x40 ft plate , why bevel 5/16 sa fillet weld should be fine . Not much of a design engineer to want  a partial pen or does he call for a full pen . ???
Reply:Even by welding on a 45  it is tight to use a K-113 gun in the web no less a full SA head ???   John
Reply:Sure is an odd design, but that's why you get the work instead of using standard WF beams.Still might be worth checking with the engineer to make sure you and him are on the same page.  Do you have an actual drawing?If this really is the job, I'd get someone with a CNC plasma and an underwater cutting table to cut this out.Let us know how this turns out, some pics would be nice."The reason we are here is that we are not all there"SA 200Idealarc TM 300 300MM 200MM 25130a SpoolgunPrecision Tig 375Invertec V350 ProSC-32 CS 12 Wire FeederOxweld/Purox O/AArcAirHypertherm Powermax 85LN25
Reply:Originally Posted by fortyonethirtyDo I have the profile of this beam correct? If so, the first thing I would do is ask the engineer why he design such a stupid looking beam. Second, what about using 3" flat bar and filling the gap? Wouldn't that be less work than cutting down the 4"?
Reply:Originally Posted by fortyonethirtyDo I have the profile of this beam correct? If so, the first thing I would do is ask the engineer why he design such a stupid looking beam.
Reply:Why don't you have the web pieces water jet or plasma cut?  Cutting 5/8" off a 3/4" FB is goign to either heat tension or a weird cut, sometimes if you don't cut off the thickness with plasma, it will angle the cut.
Reply:I wonder if there's a stock "Tee" or "W" that could be reworked to match the needed shape?Maybe narrow the flange and shorten stem of a "Tee" and then add another flange?Good Luck
Reply:If nobody there has ever used subarc, you could be in for a spanking on this deal.
Reply:Originally Posted by Fred sIf nobody there has ever used subarc, you could be in for a spanking on this deal.
Reply:Take a W10x112 Gr 50  ask if the flanges can stay at 10.415 " cut web down  and flux core together  B-U2-GF EZ way spend less money , hope you have a burning buggy or BugO to cut and weld together!  John
Reply:Why wouldn't they use a narrower standard plate for the web and make up the height with thicker flanges. Labor savings should more than cover material costsMillermatic 252millermatic 175miller 300 Thunderboltlincoln ranger 250smith torcheslots of bfh'sIf it dont fit get a bigger hammer
Reply:Originally Posted by farmshopWhy wouldn't they use a narrower standard plate for the web and make up the height with thicker flanges. Labor savings should more than cover material costs