I have to bend roll a sheet into cylinder using rollers placed in shape of pyramids. The diameter coming out is quite large so i want to decrease its diameter. How can i do it? I have to change the roller's or readust them or is there any ratio between the roller size and qutcoming diametet.
...
On the roll bender I have the top, or middle, roller is on a threaded rod on each side. You tighten it down to roll a smaller diameter sheet. You get to the right rolled sheet diameter by trial and error.
Karl
The roller that deflects the sheet between the other two rollers (the top one in pyramid rolls) can be moved in and out by the adjustment screws at each end. After each pass of the sheet you tighten them up a little until you get the diameter you want. If you don't tighten them equally you create a tapered cone instead of a cylinder.
On large units the "front" rolls adjust for the metal thickness. The "back" roll adjusts for the radius of the bend. I'ts a good idea to have a radius template bcause it's trial and error, at least it was way back when I used one. The edges at the seam will be flat for the distance it takes to engage the back roll. You have to preform the edges somehow. We used a break press or ran the material through the rolls from the backside for a few inches, again use your template.
-- Randy Replogle
My wife says I'm doing my Christian duty... annoying the hell out of her. Randall Replogle 2006
PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.