With the increasing uptake of automation across a wide range of industries, strain gauges are an important device for accurately measuring deformations.
A strain gauge is a sensor whose resistance varies with applied force. It converts force, pressure, tension, weight, and more, into a change in electrical resistance which can then be measured.
When external forces are applied to a stationary object, stress and strain are the result. Stress is defined as the object’s internal resisting forces, and strain is defined as the displacement and deformation that occur.
Because strain gauges have such diverse uses, from stress analysis in aviation and aerospace industries to medical and energy applications, they are subjected to degradation by the effects of moisture, chemical attack, or mechanical damage.
Field installation of strain gauges present stress analysts with several unique challenges, particularly when long-term measurements are required and when massive structures or inclement weather are encountered. For example, strain gauge sensor performance is easily degraded by the effects of moisture, chemical attack, or mechanical damage. As a result, strain gauge sensors require varying degrees of protection, according to the severity of the environment in which they must operate.
To protect the strain gauges, micro-measurements coating compounds are formulated specifically for use in protecting strain gauge installations from damaging environmental conditions.
Thermo Fisher Scientific recently introduced Gagekote #1, a solvent-thinned (toluene) synthetic resin that can be used as a pre-coat to protect the strain gauges from moisture, high temperature and incidental mechanical damages.
Gagekote #1 is an expansion of Vishay’s Gagekote series, which have been formulated specifically for use in protecting strain gauge installations from damaging environmental conditions. Gagekote #1 is often used as a pre-coat for Vishay’s Gagekote #5 and Epoxylite #813 and is designed to provide maximum stability to the strain gauge sensor.
One of the advantages of the Gagekote #1 is that it provides a wide temperature range coating and can easily be removed after exposure to temperatures as high as 500F (260°C).
The synthetic resin is suitable for applications in printed circuit board (PCB) testing, agriculture, civil engineering, automotive, stress analysis, aviation/defence/aerospace, education, medical, Internet of Things (IoT), robotics, Industry 4.0, consumer, process monitoring, load cell manufacturing, transportation, energy, and smart manufacturing industries.
Moisture is the most common cause of field installation failures. The Gagekote #1 provides maximum stability of the strain gauge sensor through its protective coating that is chemically stable and highly resistant to water-vapour transmission.
In order to provide maximum stability in high-moisture environments, the gauge installation should be warmed until all moisture is removed prior to applying the protective coating. Next, the Gagekote #1 coating should be immediately applied after the gauge and lead wire installation to prevent moisture from collecting in the gauge area.
The coating only protects against incidental mechanical damage, like minor objects lightly coming into contact with the installation, or very lightly dragging across it. Gagekote #1 can be purchased from Thermo Fisher Australia in Australian and New Zealand.
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In Australia and New Zealand, customers can access the Thermo Scientific portfolio through Thermo Fisher Scientific. The company’s portfolio includes a comprehensive range of high-end analytical and process instrumentation, laboratory equipment, a complete range of consumables, chemicals and reagents, and a range of services and supports to various businesses.