Wednesday, March 8, 2017

Mar. 8, 2017 Metal belt life and S-N curve

Now let us continue to talk about belt life.
Our belts and sleeves are made from metal. 
Metal experiences 'metal fatigue.' This fatigue strength is described by 'S-N curve = stress-number of bendings' as below.

 
Fatigue strength is determined by bending stress, tensile stress and crown radius of pulleys.
And in case of a welded belt, toughness around the welded area determines belt life.
Dymco strictly control this welding process to keep high belt quality.

Furthermore we have developed combination of heat treatment and rolling technology in ring-rolled belts and thin-wall sleeves.  The original welded line in these products show almost same level of hardness and tensile strength as the parent material.

Metal lives long when stress becomes less.
What about humans?  We have to stand work as well as mental stress.
Have you ever seen S-N curve of a human body?

                         DYMCO, LTD URL http://www.steelbelt.jp