Residual Stresses can be analized event trough the Ring Corse method, mainly used on large-size forgings or castings.

It is partly similar to the Hole Drilling method, but it can reach a depth of about  5 mm.

One of its main  advantages is the high sensitivity, 3 to 4 times higher than hole drilling method: this allows to reduce the influence of the error in the acquisition process.

The Ring Core is a partially-destructive test method, while the Hole Drilling Method is a not destructive one.

How it's composed

As the standard Restan MTS3000, the MTS3000-RingCore system is composed by a mechanical device, electronic devices, a dedicated software for the automatic control and back-calculation of residual stress (RSM-RC control software), digital strain gage amplifier for the automatic acquisition of the strain gage rosette data.

The mechanical device consist of a drilling unit for hollow milling cutter and of a camera for centering: the optical device is fondamental for centering the drilling axis with the optical axis through the USB Webcam.

The electronic control unit serves for monitoring the progress of the test, the drilling, the zero setting surface for determining the starting drilling position and to check USB connections.

Fields of application

Fields of application

Ring Core Method: main features

The Ring Core Method can be used to determine uniform and non-uniform residual stresses in depth, machining an annular groove around a special strain gage rosette.

The influence of core-rosette eccentricity error is lower than with the hole-drilling method: the eccentricity errors compensate each other.

Download Ring Core brochure