Hi all,
I dont have much experience with press brakes so all input welcome.
Question is, if a 40ton x 2mtr pressbrake has the correct size tooling, would it be possible to fold 200mm wide 10mm mild steel?
Cheers
You would normally use a vee width of 6 to 8 times the plate thickness on 10mm plate, a 63mm (2.5") vee will need 105 tonnes per metre of pressure, you will need 21 tonnes of force to bend 200mm so the answer is yes. that would give you a 10mm internal bend radius,
If you use an 80mm vee (preferred) then the pressure is 85 tonnes per metre which means only 17 tonnes of force required, the internal rad will grow to 13mm,
Theres a limit to what you should do with it, a 40t 2m machine shouldnt really have all 40tonnes put through a narrow bit in the middle....I seem to recall its something like 60% as a guide, but probably varies depending on the machine...prevents serious deflection or damage to the top beam.
For example on a 40t machine, you shouldnt operate at more that 24t over a distance less than the frame distance, (1.6m ish at a guess)
If it's a nice precision machine... maybe sensible, but if its an old nail, not so much of an issue.
Good point Hitch, also many people don't know how to set the press, the amount of times I've found the pressure wound fully up and the stroke length being used to set the bend, the tool bottoms out and the full force available is taken by the top beam and tooling, most of the presses I've seen in jobbing shops have been worked in the middle,
Brilliant lads.
I have done a bit of homework before I buy the machine and was fairly sure it can be done, but its good to get a second opinion from the experts.
If you're pushing the limits, increasing due opening and edge radius (bottom tool) can have quite an effect on reducing the force required, as can top tool radius.
I had a monster pressbrake, I was folding 48” 16 mm on only a 2.5 vee . Done it loads of times but this one time it bound on one side of the vee and pulled and did some fair damage to the top bolster. Too much power in a small place.
I think if the rad isn’t so critical bigger the vee the better to keep concentrated force down
If its only short bits of heavy plate would in not pay to knock up a small press like that home made thing of mine, its a bit crude but that has no trouble folding 1/2" plate.
on the knackerd one at work we bend things we shouldnt on the one side right under the ram, but dont use your nice tooling, you can bend short bits of think stuff but it really dosent do the tooling any good at all