Vishay Intertechnology has released a new series of Sealed Weldable Strain Gauges designed to provide easy installation and reliable performance for test and measurement applications, such as stress analysis testing.
The new strain gauges from Vishay Micro-Measurements are designed to accommodate spot welding to structures and components in circumstances that preclude clamping and curing an adhesively bonded gauge installation, or when high temperatures prevent the use of an elevated-temperature-curing adhesive.
According to Vishay, each gauge is pre-bonded with an adhesive to a thin 0.005 inch [0.127-mm] stainless steel carrier. To increase reliability and reduce the time and labour required for installation, each gauge is sealed in-factory, fully encapsulated with a protective coat that provides resistance to moisture.
Three leadwire configurations are available to provide the best fit for a given application, environment, and/or installation. Gauges in the R-leadwire series are designed for long-term, outdoor use in applications such as railroad and civil structures, where they may be exposed to oil and water splash or short-term submersion.
The T-leadwire series of Sealed Weldable Strain Gauges is used in larger civil structures including bridges, dams, and buildings, or in applications with exposures of up to a year in sea water. These gauges are designed to withstand exposure to water pressures of up to 500 psi, as well as short-term (up to 14 days) immersion in crude oil. A flexible, stainless steel tube provides wire routing from the strain gauge to a cable transition.
Gauges in the L-leadwire series are said to offer performance comparable to that of gauges in the T-leadwire series and – without an integrated cable transition – a more compact configuration that enables their use in applications with greater space constraints. These gauges are suited for applications with smaller strains, but anchoring the leadwire during installation can provide for strain relief.
All three gauge configurations feature resistance of 350 Ohms, a nominal gauge factor of 2.0, a gauge length of 0.125 inch, and a shielded vinyl leadwire.
Both axial and shear grid geometries are available. Vishay’s Sealed Weldable Strain Gauges have a +/-5000 micro inch strain range and a normal operating temperature range of 0 degrees C to +83 degrees C. Gauges in this series may be installed on surfaces with a radius of curvature of 3.0 inches or greater.