The S-SGBS is a strain gauged bolt. As they are ‘built’ to order, the exact specification will be established during the quotation stage as there are many variations available. There are two main methods of building the S-SGBS:
- Externally Strain Gauged
This is done by reducing the outer diameter on the shank of the bolt and applying a full bridge to this reduced area.
- Internally Strain Gauged
This is done by spark eroding a 1.6mm hole down the centre of the bolt and applying a single strain gauge on the neutral axis. The strain gauges installed are used to measure the tensile strain of the bolt. The gauges are inserted into a spark eroded hole in the bolt head. This installation is recommended if ordinary strian gauges cannot be mounted on the bolt surface. Accurate tensile measurements are possible by calibrating the bolt after the strain gauge installation procedure.
The bolts can be load calibrated using PCM’s calibration facility.