The Flexaulic Bolt Load Meter is a compact, robust and fully portable hydraulic instrument designed to measure the tension or clamping force generated in the shank of a tightened bolt. This enables torque spanners, impact wrenches or nut runners to be calibrated directly to give the required tension in the bolt. Torque measurement, which is an intermediate stage, may be eliminated.
This is of particular value in the Structural Steel industry. In order to implement the recommendations of BS 4604 Part 2 1970 on Friction Grip Bolting, a Bolt Load Meter fitted with a sample nut and bolt assembly is essential for the correct calibration of power and hand operated tools, and should be used at least once every shift.
Where torque recommendations are still required, a sample batch of fasteners may be tested and, by using an accurate torque spanner, an average torque for a safe bolt load can be evaluated. Bolt yield is easily discernible as the needle recording the bolt tension registers in proportion to the rotation of the nut; as soon as the bolt starts to yield, this relationship is immediately and recognisably altered.
The Load Meter can be fitted with a special hardened and ground thread Test Bolt assembly to record the power output of impact wrenches to determine when they should be withdrawn from use for servicing. This combination is also used to confirm that the power output after servicing is at an acceptable level.
Test Bolt assembly