Selecting of the best possible testing approach for mining and mineral handling cases, it is important to have a good understanding of the relevance of the laboratory wear tests in predicting the in-service performance of materials in high stress wear conditions. Thus, utilization of the laboratory test results more straightforward for the industry. However, generally several different laboratory test methods are needed to properly cover this kind of severe in-service conditions.

1. Application oriented wear
testing equipment
Kati Valtonen
Tampere University of Technology
Department of Materials Science
Tampere Wear Center
Alihankintamessut 16.9.2015, Tampere

3. Research Equipment
• Wear testing: Crushing pin-on-disk, Uniaxial
crusher, Dual pivoted jaw crusher, Impeller-
tumbler, High-speed slurry-pot type erosion tester,
High velocity particle impactor, Pin-on-disk/Ball-on-
disk, Erosion tester, Cavitation erosion tester, Ball-
on-block, Hammer mill, High-speed sliding test rig,
Single disc refiner, Block-on-ring, Rubber wheel
abrasion testers, etc.
• Tribology and machine elements test rigs: Test rigs
for journal, thrust, and rolling bearings, FZG, Twin-
disc test rig, Fretting wear and fatigue test rigs,
Vibration Testing, etc.
• Electron microscopes (FEG-SEM, FIB-SEM, TEM)
• Hopkinson Split Bar
• Digital image correlation system
• Mechanical testing
• Thermal spraying
• Other equipment at DMS

4. Crushing pin-on-disc
• Crushing pin-on-disc simulates mineral crushing and handling
applications, such as jaw and cone crushers
• Contact mode, high loads, large abrasive size, abrasive type, and
the comminution of the abrasive form the basis for the tests
• Variables: abrasive, disc (indirect counterpart), load (200-500N)
• Typical test parameters: 2-10 mm rock, structural steel disc, 240
N, 90 min test time ® 60 min contact time

5. Uniaxial Crusher
• The equipment crushes the abrasive uniaxially
between two specimens with a high pressure
• Controlled amount of the abrasive
• Simulates mineral crushing, like in the high pressure
grinding rolls or cone crusher
• Impacts with the hydraulic cylinder:
• 6 bar (max) 86 kN
• 5 bar 69 kN
• 4 bar 53 kN
• 3 bar 39 kN
• 2 bar 23 kN
• Typical test parameters:
• 4-6.3 mm granite
• Tool steel counterpart
• 53 kN
• 1000 cycles

6. Dual pivoted jaw crusher
• A novel reduced-size laboratory scale
jaw crusher for studying the
mechanisms of abrasive wear during
mineral crushing
– replaces/complements the standardized test
ASTM G 81-83, which has a fixed opening
angle and fixed movement between the jaws
– can be used to determine the material
properties beneficial to wear resistance at
any combination of compressive and sliding
abrasion
• Key design features:
– control of jaw movement without changing
the test geometry, enabling accurate control
of the compression-sliding ratio.
– versatile instrumentation for monitoring the
wear processes, including piezoelectric
force sensors, high speed video systems,
etc.

7. Dual pivoted jaw crusher
Compression
compression/sliding ratio 10:1
Sliding
compression/sliding ratio 1:8

8. Impeller-Tumbler Impact-Abrasive Wear Tester
• Simulates wear in mineral handling applications, such as earth moving
machinery and impactor plants.
• During the test, an impeller with three samples rotates (700 rpm) inside a
rotating tumbler (30 rpm) filled with gravel.
– Variables: sample angle, gravel size distribution, type, and amount
– One sample is the reference ® changes in mineral composition controllable
• Typical test parameters: 900 g 8-10 mm rock, 15 min cycle (4...24x)

9. High-speed slurry-pot
• Testing of wear resistant materials
and mineral abrasiveness in high
stress erosive or abrasive wear
conditions (slurry or dry)
– mining and mineral processing
applications, dredging, pumps, ...
• Key design features:
– high rotation speed: up to 2000
rpm (20 m/s in the sample tip)
– large abrasive size: 0-10 mm
– suitable for testing of metal bars or
plates, thick and thin coatings,
elastomers, and hybrid materials
– edge protection possibility
– flow conditions vary in 4 sample
levels ® requires sample rotation

10. High Velocity Particle Impactor
• Developed for the model verification and to identify the basic
mechanisms influencing the impact wear and failure behavior of materials
• Key design features:
– various angles and impact energies; projectile speed: 30…200 m/s
– suitable for various materials: metals, coatings, elastomers, hybrids, ...
– projectiles: metallic or ceramic ball bearing balls, cylinders, bullets, and rocks
– video recording: high speed camera NAC MEMRECAM up to 80 000 fps or
LaVision StrainMaster 3D DIC systems (high and low rate)
Trap wall
Target
assembly
Speed
measurement
device Smooth bore
Pressure
control
Pressurized
air tank
Specimen

11. Conclusions
• The scientific understanding of the wear phenomena and
wear mechanisms is the basis for sustainable material
solutions.
• In challenging conditions, like in mining and mineral
processing, material selection for wear parts has a
marked impact on energy and cost efficiency.
• Selecting of the best possible testing approach for each
case, it is important to have a good understanding of the
relevance of the laboratory wear tests in predicting the in-
service performance of materials in high stress wear
conditions ® utilization of the laboratory test results more
straightforward for the industry.
– Several different laboratory test methods are needed to
properly cover this kind of severe in-service conditions

12. TWC International Wear Seminar
Tribological challenges in industrial applications
28.10.2015

13. Contact
Kati Valtonen
Tampere University of Technology
Department of Materials Science
Tampere Wear Center
http://www.tut.fi/twc/
® Alihankintamessujen seminaari