Welcome! Today, we will be answering the question, “What is a Strain Gauge?” Strain gauges can be extremely useful measurement tools. This is often due to their high sensitivity. Strain gauges are used in precision load cells as sensing elements, the most accurate “load” measurement tools available. The basic definition of a strain gauge will help you understand its purpose. Next, we will move on to the working principle. This section will explain how a strain gauge works. The remainder of this article will be dedicated to the characteristics and uses of strain gauges.
Our team has collected all the relevant information to eliminate the need to read different content on other websites. We will answer your questions on the topic. Please stay with us until the end. It’s a long road ahead of us. Take a deep breath and relax. Then, continue reading this article.
What does a Strain Gage do?
A Strain gauge transducer can be described as an electrical sensor. It is used to measure strain or force. When force is applied, the strain gauge’s resistance changes and will produce a different electrical output. Strain gauges use this method to measure tension, pressure, force, weight, and force.
Two forces exist when external forces are applied to a stationary object: stress and strain. The object’s resisting force, stress, is like a pushback. A strain gauge measures the object’s displacement and deformation. They are extremely sensitive and small, so they can measure the expansion or contraction of any object.
Strain gauges are extremely thin and available in many shapes and sizes. This makes them ideal for various applications, which we will discuss later.
Strain Gauge Working Principle
The principle of electrical conductance is the basis for a strain gauge. Its dependence on conductor geometry is what makes it work. Conductors stretched beyond their elastic limits don’t burst but get narrower and longer. It also shrinks when compressed, resulting in a decrease in its resistance.
We know that resistance is directly related to R=L/A’s length and cross-sectional area given by R=L/A. R = Resistance, Length and A = Cross-Sectional Area.
Changes in the conductor’s shape and size can also affect its length and cross-section, ultimately impacting its resistance.
A typical strain gauge will contain a thin, long conductive strip arranged in a zigzag pattern with parallel lines. Because they don’t increase sensitivity, so aligning them in this zigzag pattern of parallel lines is unnecessary. The percentage change in resistance for a particular strain for an entire conductive strip is the same for every trace.
A single trace can overheat, which could change its resistance, making it hard to measure the changes accurately.
Characteristics for Strain Gauges
Below are the most important characteristics for strain gauges
- They can be very precise and not affect temperature fluctuations. A thermistor can be used to correct temperature fluctuations if they are affected by temperature changes.
- These are great for long-distance communication because the output is an electric signal.
- Strain gauges are easy to maintain and have a long life expectancy.
- Producing strain gauges is simple because of the simplicity of the operating principle and the small number of components.
- Strain gauges can be used for long-term installations. They do require some precautions when being installed.
- They are completely encapsulated to protect against handling and installation damage.
7 Remote digital reading of strain gauges can also be done.
Strain Gauge Application
The use of the Strain Gauge technology is almost limitless. Strain gauges can be used in many types of sensors. They are used extensively in the following industries: rail, aerospace, and mechanical engineering, as well as research and development. They have been used in the following applications:
- Aerospace
Strain gauges can be attached to structural load-bearing parts to measure stresses along load paths that cause wing deflection.
The Wheatstone Bridge circuits include the strain gauges. Its application areas include:
- The onboard signal conditioning units.
- Excitation powers supplies.
- The Telemetry required to read in site measurements.
- Cable Bridges
Instrumentation of bridges can be used to verify design parameters and evaluate the performance of new technologies in bridge construction and monitor and control performance.
A well-equipped bridge can be used to alert authorities of imminent failure and initiate preventive actions. It is important to choose the right sensor technology, type, measurement range, and location for your bridge to maximize costs and reap the benefits of instrumentation.
Monitoring bridges for deformation is vital as they could lead to serious accidents. Using strain gauge technology, real-time monitoring and inspection of large bridges are possible.
- Rail Monitoring
The safety of rails has been a priority for the long-standing history of Strain Gauges. It measures stress and strain on rails. Strain gauges measure the axial tension and compression without any impact on rails. The strain gauges can give a warning if there is an emergency. This allows maintenance to be planned and minimizes the impact on rail traffic.
Why are Strain Gauges Important?
In geotechnical monitors and instrumentation, strain gauges are used extensively to continuously monitor structures, buildings, cables-stayed bridges, inner tunnel linings, dams, and other structures. This helps to prevent mishaps or accidents in the event of any deformity.
It is possible to avoid injuries and death from deformities by taking timely actions. Strain gauges are an important sensor in the geotechnical area.
These structures are fitted with strain gauges. The complete data can be retrieved remotely using data loggers or readout units. These devices are important for safety and productivity.
Where to Buy Strain Gauges
There are many places you can purchase a strain gauge to suit your needs. Here are some of our favorites:
- HBM
- Omega
- DigiKey
- Amazon
You will need specific instrumentation to condition and power the strain gauge’s signal output. These are just a few HBM options, and many more Omega. Many enDAQ customers also want to add strain gauge measurement capabilities to their devices. We plan to create such a solution in the next few years.
Conclusion
This article aims to answer the question “What is a Strain Gauge?” We discussed the role of a strain gauge and how it works. To complement the previous two sections, we brought seven specifications of strain gauges. This article dealt with the application and importance of strain gauges in various appliances.