One of the technologies suitable for strain measurement is magnetoelastic technology, this is the technology that BoltSafe sensors use. With this technology, the changes in the magnetic field are measured. BoltSafe load cells are specifically designed to measure bolt load during assembly and over time, but are also capable of measuring other types of load. An example of another application of our products is in temporary construction and for Structural Health Monitoring. Knowing the bolt load in a bolted construction enhances safety, makes joints more dependable and assures better control.
The sensors are used as washers when they are used for measuring bolt load, and placed on the non-driven side of a bolted connection, preferably under a nut. When the bolt is tightened and force is applied, minor deformations occur on the stainless steel. This results in a change in the electrical resistance, that our sensor measures and uses to determine the bolt load. This is a different method than measuring the elongation of the bolt to determine the applied force, but results in the same knowledge: knowing the bolt load. Because we use magnetoelastic technology, our sensors are more compact and less expensive than other strain measurement sensors.