There is general agreement that the best way to ensure high integrity of bolted joints is to measure bolt load or tension instead of bolt torque. Historically, direct measurement of bolt load has required specialised equipment and technicians to be on-site so was unfeasible for many applications.
InterBolt, thank to a recent agreement is distributed in Italy exclusively by UVIT. This solution integrates bolt load monitoring directly into the bolt itself. The technology provides real-time load measurements to technicians during installation to ensure bolts are tensioned to the correct preload. When technicians are not on-site, bolt load data is available remotely eliminating the need for manual inspection and enabling a ‘predict and prevent’ maintenance regime to be adopted.
InterBolt measures bolt load through detecting very small changes in bolt length.
Although it is likely to seem counterintuitive to many, a bolt acts like a spring and is designed to stretch a small amount as it is tightened. This inherent bolt spring tension causes the clamping force which holds the joint together and prevents loosening during operation. The relationship between force and elongation is constant until a bolt reaches its yield point.
The sensing technology embedded in InterBolt measures bolt elongation and coverts this to an accurate measurement of bolt load (otherwise referred to as clamping force). No on-site calibration is required as each unit is preprogramed with the constant bolt parameters such as its Young’s modulus and tensile stress area, and each unit is calibrated over its full load and temperature range.
InterBolt is available in a wide range of bolts and studs, from M20 upwards.
The InterBolt technology can also be embedded into customer supplied bolts, with turnaround times of less than 28 days from receipt of customer supplied bolts.
The electronic aspects of the technology can also be tailored to suit a specific application, customer or industry requirements. This includes changes to the wireless communications standard, LED indicators and battery life.