tensile testing

2. Universal
Testing
Machine
Presented to:
Dr. Zakriya Zubair

3. Presented By
Hafiz M. Saim Irfan
18 NTU PE 1007
M. Hamza Saghir
18 NTU PE 1018

4. Contents
History
Introduction
Fields
Parts
Sample Preparation
Principle
Working
Result
Applications
Advantages
Limitations

5. History of UTM
Tinius Olsen invented the first
universal testing machine in 1880
and, throughout its history, the
company has been at the forefront of
development and innovation.

6. Universal Testing Machine
A universal testing
machine, (also
known as a materials
testing machine or
materials test
frame), is used to
test the tensile stress
and compressive
strength of materials.
A universal testing
machine offers
enhanced control
and stability
during a material
testing process.
A Universal Testing
Machine (UTM)
is used to test
both the tensile
and compressive
strength of
materials.

7. Fields
UTM provide solutions for testing the strength and performance of
1. Plastics
2. Metals
3. Composites
4. Many other materials through tensile, flexural, compression tests.

8. Parts
1. Upper cross head
2. Space for tensile specimen
3. Movable cross head
4. Space for compression
5. Table
6. Load indicator
7. Control Panel

10. Test Function
1. Tensile Test
2. Compression Test
3. Bending Test
4. Adhesion Tests
5. Pull-Out Tests
6. Hysteresis Test

11. Sample
Preparation
Sample Preparation can vary based on
the purpose of testing.
In General case, samples are cut in
dumbbell shape.
The shoulders of the test specimen
are kept broad as compared to the
testing area.

12. Principle
1
• UTM works on the principle of elongation and deformation.
2
• These machines usually use a hydraulic cylinder to create the force.
3
• The applied force is determined by system pressure which can be
accurately measured.
4
• In UTM tensile, compressive and shear forces are acting.

13. Schematic
Diagram

14. Working
The high-pressure oil pump supplies oil to the working cylinder, and through the movement
of the piston, the platen and the upper beam (upper jaw seat) are pushed upward to
perform the tensile or compression test of the sample.
The tensile test is carried out between the upper beam of the main machine and the moving
beam, and the compression test is carried out between the platen of the main machine and
the moving beam.
The adjustment of the test space is achieved by the drive mechanism (elevating motor,
sprocket, chain, etc.) driving the double screw to rotate synchronously to raise and lower the
moving beam.

15. Working
Aside from the machine, a few other components are required to make up the
complete system. A load cell is used to measure the force during the test.
A position sensor, most commonly an encoder, is used to measure the location of the
crosshead. Most machines are controlled using the position data channel, and will
move at a software controlled rate of speed according to the desired ASTM test.

16. Compression Test
In compression test, the specimen is
gripped in machine jaws and load is applied
through a screw gear mechanism by a
movable crosshead jaw.
When we apply load, our specimen is
compressed under load and its compressive
strength is shown on screen by graph.

17. Tensile Test
 In tensile test, the specimen is gripped in machine jaws.
 Load is applied through a screw gear mechanism by a movable crosshead
jaw.
 When we apply load our specimen is elongated under load and stress
strain graph is shown on screen.
 It tests the yield strength, stress and strain of a material and material samples
are tested until they yield (i.e., break).

18. Tensile Test
1. Original shape and size of the specimen with
no load.
2. Specimen undergoing uniform elongation.
3. Point of maximum load and ultimate tensile
strength.
4. The onset of necking (plastic instability).
5. Specimen fractures.
6. Final length.

19. Stress-Strain Curve

20. Bending Test
Bend testing (also flexural testing) is commonly performed to
measure the flexural strength and modulus of all types of
materials and products.
This test is performed on a universal testing machine with a
3 point or 4 point bend fixture.
During this test, the length of the material is supported at all
ends. This is done when the machines press down directly till
the time it breaks or reaches a specific distance.
Bending test helps in measuring the flexibility and stiffness
of the material.

21. Results
Universal testing machines are used to determine physical (mechanical)
material properties and material testing.
The two essential measures are the force and the length, as a change in length
under acting force.

22. Applications
Universal Testing Machine can be used and applied to perform tests on the
following samples:
• Steel Rope
• Winches
• Steel & Electrical Wire
• Webbing
• Springs
• Cables
• Nylon Rope
• Steel Chain

23. Advantages
1. UTM is used to assess the strength of materials.
2. UTM offers enhanced control and stability during a materials testing process. It also helps
ensure accuracy and repeatability.
3. The range of tests is so wide that it allows for testing a wide range of materials under
different conditions (e.g., different speeds, loading rates, forces, etc.).
4. UTM need relatively little maintenance and are easy to fix in the event of a break down.
5. They have very less chances of failure.

24. Limitations
 Produce initial system that is more expensive to build and maintain.
 Very difficult to customize.
 Requiring training of maintenance staff.
 May be difficult to use with existing system.

25. References
https://extrudesign.com/universal-testing-machine/
https://theconstructor.org/practical-guide/universal-testing-machine-components-
functions/2449/
https://www.zwickroell.com/products/static-materials-testing-machines/universal-testing-
machines-for-static-applications/
https://www.pce-instruments.com/english/measuring-instruments/test-meters/universal-
testing-machine-kat_157623.htm
https://www.admet.com/how-to-perform-a-3-point-bend-test-on-a-universal-testing-machine/