Residual Stress Measurement
The MTS3000 or RESTAN (Residual Stress Analyzer) is an instrument
designed for measuring residual stresses by the hole drilling method
developed and patented by SINT Technology.
The MTS3000 system consists of:
? An optical alignment system (to align the drilling axis to the rosette centre)
? An high speed air turbine drilling system (to physically make the hole)
? An electronic control unit (that controls the alignment-drilling system and
the measurements by analog amplifiers)
? Hole drilling operating and control software (enabling /disabling the
? Software to process the acquired data (allowing residual stress to be
calculated and determined by different methods)
The heart of the system is the alignment-drilling unit, which is used to physically drill the hole and align the cutter
with the center of the strain gage rosette by means of a cross reticule in the eyepiece. The system is also used, at
the end of testing, to obtain the measurement of the hole diameter.
Movement on the horizontal x-y plane is made by micrometer adjustments. The magnetic feet and the overhung
design allow the system to be positioned in any operating condition without any difficulty.
There are two types of vertical movements: a manual advancement of the drilling head by an adjustment knob,
and a fine positioning automatically controlled with a stepping motor. With the latter type, all drilling steps can be
made with a resolution of 1µm and feed rate from 0.03 to 1 mm/min. Zero depth detection is carried out
automatically on conductive materials by an electrical contact system.