Productivity losses due to wear-related downtime need to be accounted for alongside costs for replacement parts and maintenance.
The importance of resilient equipment, therefore, should not be underestimated. Wear resistant parts and structures are crucial to everyday operations across all industries, but particularly in mining, quarries and sand, construction, cement and concrete, coal and energy, metal works, recycling and agriculture.
MINERAL PROCESSING WEAR
{{image2-a:r-w:300}}The practice of mining and mineral processing, by its nature, involves severe mechanical interactions between metals, plus abrasive metallic and non-metallic materials.1
Extractive industries such as mining and quarrying are exposed to ever-present wear processes through extraction, handling and transfer of rocks and minerals. Thus, it makes sense that abrasive sliding and impact wear accounts for a large portion of maintenance costs across the industry.
With increasing cost pressures, many industries are trying to prolong maintenance intervals while extending asset life to minimise expenditure and maximise productivity.
But equipment downtime can be costly – unscheduled downtime even more so. Businesses are at risk from critical downtime events as they overstretch equipment capability and eschew major overhauls.
In today’s environment of asset sweating, efficiency and reducing total cost of ownership, it is imperative that the best solutions be employed to protect equipment. When repairs are undertaken they should employ the highest quality parts and processes.
Put simply, abrasive particles cannot penetrate a surface unless they are harder than the material subjected to wear.2
Hardness is therefore a crucial property in components exposed to wear.
However, the presence of hardness alone does not always solve the problem. While hardness may limit the severity of cutting actions from sliding wear, there is some level of impact wear present in nearly all mining processes, as well as structural considerations.
Impact wear, for example, requires higher levels of toughness, with many hard materials prone to cracking under impact situations.
SOLUTIONS
{{image3-a:r-w:300}}Different wear occurs according to the nature of the material, type of loading and the condition in which the work is carried out.3 Wear parts and structures must therefore possess a combination of properties to be effective.
“Wear plate” is a general term mainly used to refer to rolled, quenched and tempered steel products such as those used in the construction and lining of buckets, truck trays, hoppers, chutes, crushers, cutting edges, blades and other machinery with an inherent hardness to protect against wear and tear.
Extended testing over recent decades has shown that low alloyed steel with a martensitic, carbide-free and metallurgically pure microstructure can be considered the most effective material for use in most wear applications, taking into account its relative cost.
With a unique combination of hardness, strength and impact toughness, in part due to its optimal microstructure, Hardox wear plate is strongly suited to these applications. Hardox meets strict demands on strength, consistent quality, flatness and surface condition, and is easily weldable on-site.
With a wide range of grades and thicknesses available, correctly selected Hardox wear plate can provide the optimal wear solution – both in terms of longevity and cost.
Additionally, the integration of structural and wear parts from one material can create lighter structures and, utilising both the strength and wear properties of Hardox, can lead to reduced overall costs, increased payloads and productivity.
The knowledge, experience and processes employed by the wear parts manufacturer are also critical in meeting component lifetime requirements.
Hardox Wearparts is an international network of local companies certified by SSAB – the manufacturer of Hardox wear plate – in the production and supply of quality Hardox-based wear parts and services.
Hardox Wearparts centres are experts in the manufacture of wear parts from Hardox plate, utilising techniques that can optimise the properties of the material. With this in mind, Hardox Wearparts centres can offer a huge range of custom-designed wear parts for all industries.
As certified local manufacturers, Hardox Wearparts centres can offer solutions tailored to different circumstances.
With extensive knowledge of wear processes and materials, and by utilising SSAB’s proprietary WearCalc software, Hardox Wearparts centres can simulate and predict wear scenarios, tailoring the material selection for the required application and service life.
Working with the extensive Hardox range and design experts from SSAB, Hardox Wearparts centres can design and optimise wear related solutions to develop, manufacture and supply smarter, lighter parts with extreme performance, enabling optimised wear life and ensuring operations are not affected by downtime.
REFERENCES AND FURTHER READING
1. Olson DL, Cross CE. Friction and wear in the mining and mineral industries. ASM Handbook Volume 18: Friction, Lubrication, and Wear Technology (ASM International), Center for Welding and Joining Research, Colorado School of Mines, 1992. http://www.asminternational.org/online-catalog/handbooks/-/journal_content/56/10192/ASMHBA0002315/PUBLICATION.
2. Gates J. “Wear plate” and materials selection for sliding abrasion. Australian Journal of Mining, July/August 2003. https://espace.library.uq.edu.au/eserv/UQ:67637/jeffgates_wear_plate.pdf
3. Fernandez JE, Vijande R, Tucho R, Rodriguez J, Martin A. Materials selection to excavator teeth in mining industry. Wear 2001; 250: 11-18.