bending rebar

[flying haggis]

just how much power does it take to bend steel as easily as this???



yes i know hydraulics helps but still. and what are they building that needs rebar that size???

 

[Mickjay]

What are they building that needs rebar that size???

Tall building foundations, big machinery bases, power stations .......... etc. Having seen massive cages of this stuff I've often wondered how they manage to get any concrete in ;-)

 

[Spectric]

Hydraulics can create enormous power, simply a ratio of pressure over an area. Used to use big hand benders for both copper pipe and electrical conduit that were floor standing and heavy, now you can buy a handheld battery powered device that can bend 15 & 22mm copper which can make life so easy, literally bending pipes in situ.

 

[flying haggis]

Tall building foundations, big machinery bases, power stations .......... etc. Having seen massive cages of this stuff I've often wondered how they manage to get any concrete in ;-)

I did chat to a customer when I delivered some A142 mesh for his driveway and he said he has specified 50mm rebar for nuclear power station footing. so yes I know it will be "big" stuff that needs it. dont fancy manhandling it into position though

 

[t8hants]

One of my post retirement jobs was to bend 10, 12, & 16mm re-bar by hand in an old 'Sampson' bender, have made hundreds of shapes up for footing baskets and cages, would generally give me two or three days work and much more constructive than a gym. I am hoping I can get back to it one day soon.

 

[Mickjay]

I did chat to a customer when I delivered some A142 mesh for his driveway and he said he has specified 50mm rebar for nuclear power station footing. so yes I know it will be "big" stuff that needs it. dont fancy manhandling it into position though

Me neither. I was an RC detailer for part of my working life and it initially amazed me at the weight of a pre assembled cage, even relatively small stuff required cranage to get it into position. As for the big stuff T40 bar is 10kg/m, so a 12m beam with a dozen of those in is seriously heavy. I raise my hat to steel fixers.

 

[Boringgeoff]

They had a machine like that when I worked for the PWD in Perth WA in 1974 but wasn't capable of bending steel of that size, probably more like 3/4 inch max.
But on the point that Mickjay raised of difficulty getting the concrete in. In about 1979 Humes built a pre-cast concrete railway sleeper factory at Dampier WA and the quarrying outfit I worked for was supplying the raw materials. Their initial trials showed that the reinforcing rods in the forms were sifting out an unacceptable percentage of the largest size (20mm?) aggregate. From memory, we had to do a special crush of a smaller aggregate and they had to redesign their mix to reach the target strength.
Cheers,
Geoff.