- Thread starter ELL
- Start date
It depends on how straight the section needs to be, and on the nature of the bends.
www.stierli-bieger.com
www.fivesgroup.com
A well-anchored large vice and some heaving or pullin. An anvil might and BFH get you close. Or a rigidly built frame with a hydraulic press. There's also flame straightening.
www.boconline.co.uk
Metal Straightening | Stierli-Bieger
Metal Straightening ➨ Straighten profiles, plates or welded structures ✔ straightening machine perfectly constructed and welded ➨ Suiss Quality Stierli-Bieger
www.stierli-bieger.com
Straightening
Bar Straightener Bronx bar straighteners cover a range of 1.5 mm – 300 mm in diameter and hold high production speeds of up to 180 mpm. ...
www.fivesgroup.com
A well-anchored large vice and some heaving or pullin. An anvil might and BFH get you close. Or a rigidly built frame with a hydraulic press. There's also flame straightening.
Flame Straightening
Flame straightening uses LINDOFLAMM® special burners and acetylene gas to correct distortions in metal that occur during manufacturing processes.
www.boconline.co.uk
Agroshield
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Four passes through one of these, experimenting with roller pressure. You might have to put a small, constant bend into it with the first pass and then remove it with the 180 degree pass. After the first length, you will motorise the roller.
This is what is used for circular wires. As in the link above, a super-duty version would work for box section:
techna.co.uk
This is what is used for circular wires. As in the link above, a super-duty version would work for box section:
Witels Albert PR NT Series Straightener - Techna
techna.co.uk
chrismac
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depending how bad, ie if pulling it in the vice or running it through some rolls is not going to fix it, I would be looking at working with the bits between the bends I think, this needs to be a slick operation to get it straight or you will be wasting more time then potentially the box section is worth.
KemppiFrog
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I used a hydraulic jack in a big frame to gently curve 40x20x2 ss section for a boat's railing. doing little pushes at 25cm distances, it came out as a fair curve. Did take a bit of time, but it wasn't a constant curve, varied along the length and measured by offsets.
Depends if it curved or kinked?
Depends if it curved or kinked?
Nomad
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Hi. Do you have any uses lined up for it?
I often use salvaged materials (mainly metal & timber, some large polycarb sheets etc, todays job was done with salvaged commercial rubber flooring..).
Work out what's needed - mark out the req'd size avoiding any badly damaged areas - fix any defects inside the section I've marked...
For specific jobs it's often more cost effective (if you include your time) to just buy new
KemppiFrog
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Way back but we got an urgent job to build two machines to make the rebar stirrups for the piles they used to support the Drax Power Station.Four passes through one of these, experimenting with roller pressure. You might have to put a small, constant bend into it with the first pass and then remove it with the 180 degree pass. After the first length, you will motorise the roller.
This is what is used for circular wires. As in the link above, a super-duty version would work for box section:
Witels Albert PR NT Series Straightener - Techna
The Swedish outfit that was supposed to supply had a wobbly and coudn't.
Basicly a rotating face plate that had the five pins to form the 'cage' with rollers that pulled down to overbend, then a system that pushed the wire off the pins onto rods on a slightly smaller radius as a spiral.
The feed was from BIG rolls of thin rebar that ran through 5 V rollers that straightened it out (as in the link from Argoshield)
We went to the site for a check up and they had been bashing the rebar round pins in tree stumps.... Wereas our machines just poured off the spirals at around 40 rpm (might have been more)
Def saved their bacon on overrun and we should have charged way more, just for that.
I seem to remember there were around 250k piles set in the project...
Bit like the 'suites' that turned up one day and asked if we could do one off GRP mouldings. (They had seen one of our trailers in the Company car park with GRP mudguards)
A bit disapointed that we didn't have a subcontractor doing them, they unrolled some drawing for my father to look at, with some very complicated ducting. They had a section in the car in stainless, and very nice it was too. On finding father had trained in aerodynamics prewar, they cheered up and explained.
It was Concord's aircon ducting around the engines and they were having trouble getting it right. Their own (Hawker Siddley) plastics shop was overworked and they needed someone to produce several ducts for wind tunnel flow tests.
Fun stuff back then..
