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Ed Huntress Ed Huntress is offline
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Default Steel for Olympic Barbell

On Mon, 10 Nov 2014 10:43:15 -0500, "Steve W."
wrote:

Ed Huntress wrote:
On Sun, 09 Nov 2014 13:05:58 -0600, F. George McDuffee
wrote:

On Sun, 9 Nov 2014 09:47:38 -0800 (PST), Sandarpan Mukherjee
wrote:

snip
The bar will be at least 190000 psi tensile st=
rength with 170000 psi yield strength.
/snip

You are talking about very expensive HY210 submarine hull
steel. I don't know if this is available in the civilian
market.

These specs seem excessive for even Olympic class lifters.
A quick google search indicates less than 300Kg for any
single lift. http://tinyurl.com/lmoxl6a


He's around the high end for heat-treated 4340. The thing is, with
yield of 170 kpsi and ultimate tensile of 190, when that bar is
overloaded, it's going to go "Bang!"

It doesn't sound like something you'd want in a barbell. g


Actually his numbers are at the minimum that are allowed in an Olympic bar.
The lower end bars are 170K tensile. The good ones are up around 210K!

The idea is that the bar has to flex when you lift, that helps you by
storing energy that helps you flip during the lift. The bars also have
bearing inside the weight sleeves so that as you lift the plates don't
apply any torque to the bar and spoil the lift.

I have friends who lift HEAVY and most seem to use Eleiko, York or
Werksan bars. They are not cheap but they do seem to last.

When they do clean/jerk lifts that bar looks like a wet noodle.


That's really pushing what you can do without really good material
specification and very expert heat treating. You can get the ultimate
tensile strength, but avoiding brittleness at that level of tensile
strength is a job for the experts.

--
Ed Huntress