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Ennio Curto
03-28-2008, 11:22 AM
More information about residual stress tester


The residual stress in a metal do not depend on its hardness, but from the module of elasticity or Young module and from its chemical composition (density).
The hardness of a metal indicates its ability to absorb energy elastic, plastic or kinetic energy, but through it not possible to determine the value of residual stress. In a metal with the same hardness we will have a different values of this stress. Therefore, the problem will be to measure the values that vary so exactly proportional to the residual stress values in a given metal.
The residual stresses tend to equilibrate themselves in the surface of the material.
The measurement made with all the major methods, X-ray, string gauge (destructive), optical etc. the residual stress is determined between the measuring the displacement of the equilibrium point the reticule crystalline.
The method discovered analyzes the value of acceleration vibratory generated by an impulse to constant energy with the subsequent reaction elastic (elastic field) from the metal, The equipment does not recognize the value of compression from that of tensile stress. It gives the value of the space resulting or volume but with the applying of a triaxial accelerometer we can have forces values axis x, y, z.
You will realize the convenience of this apparatus.
1) Portable and easy to use and very rapid.
2) NDT non-destructive examination (strain gauges).
3) Repeatable in unlimited number of times.
4) Not dangerous (X-ray).
5) Do not expensive. Effective for weldings, hardened treatments, vessels control, bridges, pipes line, aeronautics, NDT inspection for every metal types.



Ennio Curto

Ennio Curto
03-15-2009, 07:09 AM
I want to thank residualstress ,com for this forum.

Ennio Curto

For more information pease see web site:
www.scribd.com/doc/8661767/HANDHELD-RESIDUAL-STRESSES-MEASUREMENT-NDT

Thank you.

Robert
04-17-2009, 10:13 AM
I see in your article that the system can not distinguish tensile and compressive stress.

I don't see how this can be used for general applications if you only get a magnitude of stress and not a sign. The sign is the most important part as in many failure issues around residual stress it is the result of having tensile stresses present.

Ennio Curto
04-30-2009, 10:34 AM
Robert.

Sorry if I answerd now but I havn't receved your message before. The sum of the axial components can be positive or negative but the result does not change, the apparatus gives the absolute stress value resulting. Is easily understood his direction in heat treatment, welding structures, and for determination the material stress state.

Best regards
Ennio Curto

Robert
04-30-2009, 03:38 PM
If you do not know the actual sign of the stress then I do not see how this is useful. You would be making an assuption as to the actual stress state.

Ennio Curto
06-29-2009, 03:44 PM
Dear Rober.

You have reason, with this system is impossible to know if the stress is positive or negative, like all the istruments than work on the weve trasmission.
burt is very easy with exaples, studies, loads direction and other simple device to determine.

Regards Robert.

Ennio

Write to me becouse i know you are a specialize in residual stress, we can speake