5 Tips for Utilizing One Universal Testing Machine For Multiple Applications
1- Material Properties & Test Parameters
Prior to committing to a testing machine, quantify the performance and specifications of your material/product. Material properties such as the required maximum force capacity and specimen dimensions as well as test parameters such as the required speed of testing will help narrow down the options to select the right universal testing machine. If any ASTM, ISO, or EN test standards will be followed, review the standards in detail. Ask your ADMET Account Director to provide information on the recommended test equipment for each test standard. If you are planning on running different types of tests with one UTM, ensure that there is adequate test space to accommodate all fixturing and specimens.
2- Test Results & Reporting
Choose the mechanical properties you would like reported at the end of testing. The controller and software package should be able to run the tests and provide the required data. If live capabilities are required, look for a software interface that provides live data. If graphs are needed in the results report, ensure the software provides graphs.
3- Test Fixtures & Mounting Options
If you are planning to run different types of tests such as tension, bend, compression, different test fixtures will be required. ADMET offers a special fixture design that helps maintain efficiency for applications requiring the use of different test fixturing.
The eXpert 2657 configuration discussed below is an example of a testing system used for multiple tests requiring different test fixtures. The eXpert 2657 electromechanical UTM comes with a pair of high-capacity wedge grips with grip/fixture adapters that are mounted on the grips. These adapters allow the wedge grips to stay on the testing machine as the operator can mount other fixturing such as an ASTM bend fixture and high-capacity compression platens directly on the dual-fixture adapters.
To run tensile testing, simply use the wedge grips that stay on the UTM. To switch to a compression test, use the adapters on the top and bottom wedge grips to mount the compression platens and place the compressive specimen on the bottom platen. Finally, for bend testing, remove the compression platens from the wedge grips and mount the bend fixture. High-capacity wedge grips as well as other high-capacity test fixtures are often heavyweight and consequently not easy to dismount. This dual-fixture design saves time while facilitating the operator’s work.
4- Load Cell & Transducers
If possible, choose a load cell that covers the force range of the different types of tests that you are planning to run. The load cell should work for both tension and compression and be calibrated in both directions. If multiple load cells are needed, piggyback adapters may be selected to mount the lower capacity load cell directly onto the high capacity load cell so the high capacity load cell doesn’t need to be removed from the system.
Displacement transducers and strain measurement devices may be required to run further testing on the UTM. Refer to the standardized test methods or the test methods of your choice to determine whether the crosshead displacement data is sufficient or if additional displacement transducers will be needed to gather the most accurate data. Axial extensometers are often clipped directly on the specimen whereas displacement transducers require a fixture mount or a yoke assembly. ADMET Sales Engineers will work with you to ensure the selected displacement transducer is set up correctly with the remaining components of the testing system.
5- Calibrations
If using the same universal testing machine for multiple tests, talk to your calibrator and ensure the system is calibrated in the required directions. ASTM/ISO calibration certifications are separate for calibration in the tension direction and the compression direction. Similarly, specify the ranges of speed and displacement that will be utilized for all testing to ensure the whole range is covered in calibration.
ADMET provides calibration services and is ISO 17025 certified. Whether you are planning on a new system purchase or will be using a remaining UTM for a wide range of testing, discuss how we can cover your calibration needs with one of our Engineers by clicking here.
One Universal Testing Machine for Three High-Capacity Tests
ADMET eXpert 2657 testing system is a floor-standing universal testing machine from the eXpert 2600 series of electromechanical test frames. The eXpert 2657 system is rated to 300kN (67,450 lbf) and a maximum speed of 508 mm/min (20 in/min).
The eXpert 2657 configuration discussed below was designed to run three different test types (tension, compression, and flexion) with a specialized tensile fixture design that doesn’t require dismounting between tests. The system was equipped with MTESTQuattro controller and software and a touchscreen computer to view real-time XY curves and live numerical data.
Configured Fixturing for Three Test Types
1- High-Capacity Tensile Testing
Test Type: Tensile testing
Featured Test Standard: ASTM E8, ASTM A370
Featured Test Fixture: Wedge Grips on an eXpert 2657
Tensile testing is imperative for ensuring a safe, high-quality material and avoiding the major liabilities associated with providing non-compliant products. The ASTM E8, a standard specification for measuring the tensile strength of metals, provides data on the strength and ductility of metals under uniaxial tensile forces. Tensile testing on certain materials such as metals and composites requires high-capacity load frames and test fixtures.
High-capacity wedge grips used with the eXpert 2657 system are rated up to 300kN. Options up to 500kN capacity are also available. The wedge grips come with a door crank handle to open the door mechanism and mount specimens between the jaws. This design can be ordered with other fixturing such as compression platens or bend fixtures mounted directly on adapters on the wedge grips to allow running two different tests without having to remove the heavy-weight high capacity tensile fixtures in between tests. This design helps maintain efficiency when running different types of tests requiring different test types requiring different test fixtures.
2- High-Capacity Bend Testing
Test Type: Bend (flexural) testing
Featured Test Standard: ASTM C1609, EN 14651
Featured Test Fixture: ASTM C1609 Averaging Flex Fixture Assembly on an eXpert 2657
ASTM C1609 is a testing standard conducted to determine the flexural strength and the residual stress of fiber-reinforced concrete specimens. EN 14651 is a European standard to determine the flexural tensile strength and the limit of proportionality of metallic fibered concrete on molded test specimens.
The test setup to run ASTM C1609 with the eXpert 2657 testing system included the ASTM C1609 averaging flexure fixture, yoke, and displacement transducers.
The bend fixture design to run this testing is outlined in ASTM C1609 and has recently been revised with important changes to the flexure fixture. The fixture supplied with the system included supporting rollers that rotate on their axes throughout the duration of a test and conform to ASTM C1812/C1812M. The upper loading noses conform to the requirements of ASTM C78/78M.
A closed-loop controller, MTESTQuattro is able to maintain test speeds at very low rates as required by ASTM C1609. MTESTQuattro controller comes with 8 channels of input. For ASTM C1609, the load channel as well as the axial and transverse axial channels were used to gather data.
3- High-Capacity Compression Testing
Test Type: Compression testing
Featured Test Standard: ASTM C109
Featured Test Fixture: Compression platens on an eXpert 2657
Compression testing is conducted to measure compressive strength which is the maximum stress a material can withstand before it yields or breaks. Other compressive testing properties include modulus of elasticity, yield stress, and deformation.
In addition to tension and flexion tests mentioned above, the eXpert 2657 universal testing system is also ideal for high-capacity compression tests. Picture below shows metal spring specimens tested in compression using compression platens mounted directly on the tensile wedge grips. With the dual fixture design, high-capacity wedge grips stay mounted on the testing machine and do not need to be removed to run other tests.
Conclusion
By quantifying the material properties, required test results, and selecting the right equipment, the same universal testing machine can efficiently be used to run multiple tests. Refer to our tips to select the right equipment and discuss your testing application with one of ADMET Sales Engineers. Contact us here.