- Thread starter Welderpaul
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Lots of good info, thanks all.
I think the way forward is to cut them, allow them to bend, then deal with straightening afterwards. Trying to stop them bending is a dead loss.
Trying to work out how to get them in the pressbrake, and which way they need to be bend.
I think the way forward is to cut them, allow them to bend, then deal with straightening afterwards. Trying to stop them bending is a dead loss.
Trying to work out how to get them in the pressbrake, and which way they need to be bend.
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Depends how much they move really, as i said, we pressbrake big ones back straight.
2 Plates with two bits of decent sized solid of heavy box welded on, gap between the two just slightly more than the web thickness. Might not work so well on your sized beam though, especially being tapered.
2 Plates with two bits of decent sized solid of heavy box welded on, gap between the two just slightly more than the web thickness. Might not work so well on your sized beam though, especially being tapered.
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we recently took down a steel tapered column/rafter 40m span building where beams were approx 1200mm deep at one end down to 500mm over 10m and all sections were made up from plates, the webs were welded to the flanges continuously on one side only-every thing was perfectly square and im sure with a simple jig you could make these up alot easier and with greater tolerance
i think i would try to weld 300mm alternating on eitherside of web but that depends on your jig
i think i would try to weld 300mm alternating on eitherside of web but that depends on your jig
Drains
Yeah, nah.
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Why not?
Got to say, i'd fab them (shrinking 450mm of web evenly over 3m will take an age).
Fab them and stitch. Don't fully weld them for God's sake. Try it out on one but do it slow, let it cool as you go, check the result.
Then rig up the other 20 all in a row and skip from one to the next, even stitches each side, let the first welds cool, do the next unit, start back at the beginning.
How much weld is actually required for appropriate strength?
You need to go back to the designer and talk this through with him. Besides you will get banana beams, cutting the bottomflange off an I beam will weaken it incredibly. Without doing calcs I would say that it would reduce the beam strength by 80% towards the cut off flange and about 30% away.
Also think about the consequences, if they fail and someone dies who gets locked up? You will be partly to blame, the HSE love to take people to court.
Also think about the consequences, if they fail and someone dies who gets locked up? You will be partly to blame, the HSE love to take people to court.
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We are the designers. Well, our Structural Engineer is. We are on a design, fab and install contract. We sub out the strucutral design. The outline calcs have been done, and prove the tapered beam is man enough to do the job within the acceptable deflection limits. The issue is how we deal with the fabrication side of things.
Looks like we have found a company that can roll the beam back straight. We have no chance of trying to stop it bending while cutting.
Looks like we have found a company that can roll the beam back straight. We have no chance of trying to stop it bending while cutting.
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He didnt specify it. The Architect specified it. We just get things to work.
Ah that explains it. I have to work with those idiots all the time looks over substance every time and its us poor engineers that have to sort the mess out.
re taper beam
I have made a sizeable quantity of tapered and castellated beams over the years and have found that stitch cutting the web with a plasma as the most effective method as it limits heat input and distoration. Plus on the beams you are fabbing there is a sizeable web section remaining which should limit distortion.
I have made a sizeable quantity of tapered and castellated beams over the years and have found that stitch cutting the web with a plasma as the most effective method as it limits heat input and distoration. Plus on the beams you are fabbing there is a sizeable web section remaining which should limit distortion.
