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DougC DougC is offline
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Default Steel vs. kevlar cable, breaking strength vs. working load?

On 9/1/2011 8:55 AM, DT wrote:
In ,
says...

For a project I can use either kevlar cord or thin steel cable.
The breaking strength for a given diameter (at least in the small
sizes) comes out very very close to each other: in one instance, .31"
steel cable was rated at 184 lbs, while .3125" kevlar cord was rated at
175 lbs.


This doesn't seem right, 5/16" steel cable has a breaking strength of
around 10,000 lbs.


oops,,, put another zero right of the decimal. .031" & .03125"....


The matter is in regards to the wire used in bicycle tire beads.

Tire & rim systems have changed over time and many kevlar-bead tires are
designated as not suitable for newer tubeless rims where steel-bead
tires are--yet the bead diameters (and breaking strengths) of both is
very close.

The elongation under breaking of kevlar ranges from as little as 1.2X
steel to ~2x steel wire of the same size. Might or might not be an issue...