The correct machine purchase decision starts with defining your current testing requirements and correctly estimating the future requirement .The selection of a universal testing machine should be based upon the features it offers and ability to perform tests in accordance with a particular testing standard that may be required.

1. Electromechanical or Hydraulic: The electromechanical or screw driven test frames typically use an electric motor and two elevation screws to run the cross-head up and down. They offer following advantages

• A large range of test speeds
• Longer crosshead travel distances of up to 100 inches or more.
• Better speed and position accuracy
• High position resolution.
• Better speed control in computerized systems

1. Benchtop or Floor Model: Depending on capacity and physical height and weight, machines may be offered as table-top or floor standing models. The end user needs to make sure the machine will be adequately supported on an existing test bench or will fit inside the planned test location with sufficient ceiling clearance.
2. Single Column vs Double Column : Single column testers are typically employed for applications requiring lower forces 10 kN. Single column machines are suitable for bench mounting and can be used in a lab or production environment. Double column testers are generally specified in higher force applications. A double column test frame can be configured for bench mounting or floor mounting.
3. Load Capacity: It is important to select a testing machine with a force capacity greater that the maximum testing force expected in your test program.
4. Travel: Always  consider a larger capacity machine to allow for expansion of your current testing needs. Factors to decide must include

• Dimensional specifications must cover distance between columns,
• Vertical test space
• Enough vertical travel to sufficiently expand the sample being tested. Consider the height of grips and fixtures which reduce the effective vertical travel

6. Measurement Parameters: The system should be able to measure all necessary parameters as per your requirement
7. Analog, DRO based or software based - The simple UTM is equipped with a digital read out display unit to record the peak force acquired when the load is applied to a material or component. Most UTM manufacturers offer computer acquisition or computer controlled test systems. Tests requiring peak force or peak psi can be obtained simply with a digital read out. Test methods requiring computed  strengths, yield values, extension values, and elongation calculations typically need a chart or computer in order to plot a stress vs strain curve or force vs machine displacement curve. Software package must be equipped with  data acquisition, statistical analysis, pass/fail criteria, report generation while building a queryable data base of tested samples.
8. Selection and control of test speed as required by the standard.
   • Specimen are speed sensitive i.e the results change with the speed
   • Speed must correspond to the system capability to capture the signals from load cells- it should not be high enough.
9. Test Method - Testing standards and procedures are published by a variety of standards organizations. Some of the most significant standard organizations include ASTM, ISO, Military, JIS and DIN.
10. Extension Length - Specify the extension length that you want to check
11. Grips
    • Fixed or self aligning
    • Threaded or collar type
    • Shape- Wedge, Pin
    • Smooth faced or Serrated
12. Reports 
    1. Graphical
    2. Excel or PDF
    3. Cover all 15 points of D638
13. Extensometer

The UTM will need to have additional channels to record force, crosshead travel, extensometers, linear variable displacement transducer (LVDT), or time acquisition. Most metal testing requires an extensometer attached or optically scanning or video recording to measure the strain of the material

14. Accuracy of the measurement results
15. Overload protection
16. Deflection compensation
17. Precision or Least count of measurements
18. Environmental requirements- Also consider the distance between columns is critical when incorporating very large fixtures, special grips or hot/cold chambers.
19. Repeatability & Reproducibility
20. Start Test Condition or End test conditions - The computerized UTM can also be programmed with ending test conditions, such as ending the test at a defined force or position or break sense, a specified percentage drop from peak force.
21. I/O data channels
22. Knowing the standard to be met allows the user to determine which features are needed or how many channels of acquisition must be included
23. Training & Support - Proper training to ensure the operator is able to properly set up any required test fixtures and properly perform the test to completion. Screen sharing options and remote access allow manufacturers and other users to train, provide support, and troubleshoot tester problems via the internet.