There is a wide range of strain gauge types available online in the UK. These range from wire strain gauges to foil strain gauges, linear strain gauges (similar in core principle to a linear variable differential transformer, or LVDT), half-bridge and full-bridge strain gauges, compression load cells, beam load cells, force sensors, and multiple other variants.
Choosing the right type of device for the strain gauge applications you are tackling is key. Doing so will always give you the best strain gauge performance in terms of optimal accuracy and reliability. When choosing between different types of strain gauges for a defined purpose, there will always be several important considerations to bear in mind.
Firstly, you will need to be clear on what specific type of strain force you are measuring (mass, torque/torsional, axial strain, pressure, compressive, bi-directional, material fatigue, shear etc). You will also need to know what type of durability test you will be running. This could include experimental stress analysis, residual stress analysis, microstrain, deformation, material longevity/lifetime analysis, load analysis, thermal stress, temperature effects, or various others.
Based on your answers to the above, you will then have to decide between numerous models and types of strain gauges based on their main physical properties. These include:
- Strain gauge geometry - this is the number of tracer grids a given device includes, how they are arranged, and the resulting active grid length
- Strain gauge series and connections - how the device is physically constructed and laid out, and if/how it is connected in sequence with others e.g. wire gauge lengths
- Device electrical resistance - measured in Ohms
- Material temperature response, performance and adaptation - the type of gauge you choose will need to be matched to the thermal characteristics of the material and install location you are monitoring