SUMMARY

Experimental research plays a key role in solving wear problems. The following four novel wear test devices were developed in the DEMAPP programme: a dual pivoted laboratory jaw crusher, an impeller-tumbler impact-abrasion tester, a high-speed slurry pot tester, and a high velocity particle impactor (HVPI) for wear model and simulation validation. The test devices were designed to simulate the wear systems in typical end-user applications of the wear resistant steels

RESULT

A dual pivoted laboratory jaw crusher

The novel dual pivoted laboratory jaw crusher can be used to determine the material properties beneficial to wear resistance at any combination of compressive and sliding abrasion, while the standard laboratory jaw crusher has a fixed opening angle and fixed movement between the jaws. In addition, the dual pivoted jaw crusher facilitates measuring of the work (energy) in comminutive processes and enables the assessment of the abrasivity and crushability of minerals. The results of these tests have already provided invaluable data for modeling and understanding of the wear behavior and wear mechanisms in abrasive crushing environments. In the industry, the test device and the accumulating data and knowledge can be used for example in the process planning and development of process optimization tools for companies dealing with crushing, processing or moving of natural rocks, such as Metso Minerals and Ruukki Metals.

A high-speed slurry pot tester

In industrial slurry pumping, the speeds can be up to 30 m/s and the size of the particles, which work as abrasives in the system, can vary from micrometers to several centimeters. With the high speed slurry-pot type erosion tester it is possible to achieve high speeds with large abrasive size for simulating slurry pump and mineral processing conditions. This method is applicable for a wide variety of materials, including for example different types of steels, elastomers, and coatings.

High speed slurry-pot type erosion tester

An impeller-tumbler impact-abrasion tester

Earth moving machinery has to withstand heavy wear caused by loading and unloading of soil for example into buckets and tipper bodies. Especially the edge parts are subject to heavy wear. To simulate these conditions, an impeller-tumbler type impact-abrasion wear testing equipment was designed and constructed at the Tampere Wear Center. The samples are attached to the holder as impellers, which rotate at a high speed inside a drum filled with gravel. The sample angle, the rotating velocities of the impeller and the tumbler, and the amount, size and grade of the abrasive can be easily varied.

Impeller tumbler

The High Velocity Particle Impactor

The High Velocity Particle Impactor (HVPI) was designed to produce single and multiple impacts of solid particles on different types of materials in order to identify the basic mechanisms influencing the impact wear and failure behavior of materials. The device is used for the determination of material properties and, especially, for the verification of the numerical modeling and simulation results. The HVPI device is capable of shooting projectiles of different shape and composition launched by pressurized air through a smooth bore at velocities ranging from 30 to 200 m/s. 

MOTIVATION

Wear in its various forms is a common cause for material failures, frequent replacement of parts and components, general loss of productivity, as well as indirect losses of energy and increased environmental burden. Improvements and new innovations in the wear resistance of materials will have a great impact on the energy and cost efficiency, environmental issues, and safety requirements that the industry is increasingly facing. The experimental research plays a key role in solving various practical wear problems and, especially, in enhancing the scientific understanding of the wear phenomena and wear mechanisms.

APPLICATIONS/
IMPACT

The developed dual pivoted jaw crusher has proven a valuable tool for better understanding of the combined effects of different crushing parameters and mineral properties. The device and the accumulating data and knowledge will be used for example in the process planning and development of process optimization tools. Moreover, the test results have been utilized in the steel development work at Ruukki Metals. For example, the steel compositions and process parameters have been optimized to obtain the desired microstructures and mechanical properties.

MAIN CONTACT

Prof. Veli-Tapani Kuokkala, Tampere University of Technology

Pekka Siitonen, Metso Oyj

PROJECT PARTNERS

Tampere University of Technology, VTT Technical Research Centre of Finland, Metso Oyj, Ruukki Metals Oy

AUTHORS

Author missing

Veli-Tapani Kuokkala

veli-tapani.kuokkala(at)nospamtut.fi

Tampere University of Technology

Author missing

Kati Valtonen

kati.valtonen(at)nospamtut.fi

Tampere University of Technology