- Thread starter fishpat86
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How about this question;
How much force would a plain steel rod of 25mm diameter with a span of 1400mm take before it bends if the load was in the middle? I'm hoping it is more than 19600N.
How much force to bend this bar in the middle?
http://cgi.ebay.co.uk/Mild-steel-br...464883&cguid=c3448fa312d0a0aad0e55585ffb270c6
How much force would a plain steel rod of 25mm diameter with a span of 1400mm take before it bends if the load was in the middle? I'm hoping it is more than 19600N.
How much force to bend this bar in the middle?
http://cgi.ebay.co.uk/Mild-steel-br...464883&cguid=c3448fa312d0a0aad0e55585ffb270c6
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Depends how much 'bend' or deflection is acceptable. A bend could be anything from less than a mm say, to bent like a hairpin. Then theres elastic and plastic deformation.
Bright bar, or BDMS is tougher than ordinary mild steel.
1kg - 9.81 Newtons, so very roughly speaking your wanting to put the equivalent of 1997 kg mass on it. If it's applied as a point load at the centre of a 1.4 length its going to bend double unless the ends are restrained, but even then its going to bend/get close to snapping.
What are you planning?
Bright bar, or BDMS is tougher than ordinary mild steel.
1kg - 9.81 Newtons, so very roughly speaking your wanting to put the equivalent of 1997 kg mass on it. If it's applied as a point load at the centre of a 1.4 length its going to bend double unless the ends are restrained, but even then its going to bend/get close to snapping.
What are you planning?
I'm building a power rack for my gym. This consists of a cage with holes drilled in the upright supports and then a bar is slotted through the cage to 'catch' the barbell should you fail while performing a squat or bench press etc etc. I want to keep the size down to around 25-28mm diameter so I don't have to compromise the strength of the frame.
The grades these days signify the yield stress, so S235 has a min yield of 235N/mm2, the next grades are S275, S355 and S420. Therfore you will need S420. As far as I know its not that common. Could you use a thicker section of S355 as its probably more common.
The maximum I can go to is 28mm.
I also have no idea where to buy or how to ask for these steels as I have very little knowledge of this game so far.
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A dynamic load then? No wonder its high. I think your trying to engineer the impossible.
If you really cant increase section size, can you look at using springs/buffers in some way to reduce the shock load?
If you really cant increase section size, can you look at using springs/buffers in some way to reduce the shock load?
This might do it. Its En8 so the yield should be high enough unless its been normalised or annealed. Ask them for the yield, they might have a test cert
http://www.metals4u.co.uk/detail.asp?cat_id=138&prd_id=2798
http://www.metals4u.co.uk/detail.asp?cat_id=138&prd_id=2798
