What is Universal Testing Machine / UTM?
Universal Testing Machine or commonly called UTM is a general purpose machine used to check tension load and compression load applied via different fixtures to test materials. Any test material that has elongation or compression properties can be tested in UTM machine. Test sample can be any material, component or a structure.
In different industries or sectors, universal Testing Machine is referred differently but it serves the similar purpose. For example, it is referred as ‘tensile strength tester’, ‘tensile testing machine’, ‘compression testing machine, ‘compression strength tester’, etc. For food industry, it is specifically marketed as ‘Texture Analyzer’
Universal Testing Machine generally consists of following parts:
Load cell is called as the heart of UTM. This is a load / force measuring sensor which determines the level of accuracy of the final results. Load cell is required to calibrated on time depending on the frequency of your use.
Machine frame / Load frame
The machine frame is one of the factors which is taken into consideration while calculating maximum load capacity for the UTM. Normally, UTM’s are classified into 2 categories based on frame capacity:
- Single Column universal testing machine
- Double column universal testing machine
So, it can be stated that double column machines have better Max Load Capacity than the Single column machine.
- The maximum extension a Universal Testing Machine can provide is called extension range. Some tests require the machine’s extension to be more depending on the sample elongation properties; while other test can be performed with lesser extension too.
Some of the external accessories used along with used with Universal Testing Machine are:
- Extensometer is optional accessory used to measure the sample extension while testing accurately. Generally, extensometer is used for Modulus calculations i.e. stress – strain measurement. There are 2 types of extensometers namely contact type and non-contact type. Non-contact type Extensometer’s are further classified into Laser Extensometer and Video Extensometer.
Test Fixtures / Accessories
- There are many tests which can be performed on a UTM, so depending on the testing requirement the test fixtures are made. These test fixtures will vary with the type of testing to be performed on UTM. For most of the tests, international / national standards (like ASTM, ISO, BS, etc.) are already available; so the fixtures are manufactured according to these standards only. If standards are not present, then manufacturing of customizable grips is done. Some of commonly performed tests and test fixtures to be used are discussed in brief below this article: Top 10 tests performed in UTM.
- Purpose of output mechanisms in case of Universal Testing Machine is to display the measured value. There are different types of output mechanisms available; in older version of machines; dial gauges, chart recorders were used with these versions results were to be observed by user and noted manually. But the new evolved versions of UTM are available with data acquisition computer software’s; which are highly sophisticated and provide wide array of result measurement and analysis of the same result in very efficient way.
Environmental chamber / Conditioning Chamber
- Generally, in environmental chamber temperature and Relative Humidity (RH) is generated as per required conditions. This is an optional accessories which can be provided with UTM. Environmental Chambers are used along with UTM if there is a requirement of sample to be tester on certain temperature and humidity parameters. Also, pre-conditioning can also be in environmental chamber.