COMMINUTION AND CRUSHING
Outotec now offers a 7-Axis Mill Reline Machine
for manipulation of the liners inside the mill ensures safe, efficient, and reliable operation.
“ We wanted to make relining safer,” says Ruari Soutar-Dawson, Product Manager for Outotec’ s Mill Reline Machines.“ It ' s one of those high risk environments, so you need to either design out the hazards all together, or implement proper safety equipment and systems to make sure people are as safe as possible.”
The company believes that its Mill Reline Machines are the safest on the market.“ Featuring remote control operation, state-of-theart electro-hydraulic proportional control blocks with advanced fault detection, and safety rated components and systems; safe machine design is a primary focus.”
“ We have rated it as a crane, which means that it has to comply with much higher safety standards than other competitor equipment that ' s currently on the market,” says Brian Berger, VP of Outotec ' s Grinding product line.“ In order to define it as a crane it must meet multiple different safety standards, including load limiting devices and redundant control systems both in electric and hydraulic controls.”
Outotec’ s beam MRMs are highly specialised pieces of lifting machinery designed to safely and efficiently replace wearable grinding mill lining systems. The machines have multiple options for beam and crane sizes of differing working load limits to suit a wide variety of mills.
“ It has been an immensely challenging, and rewarding opportunity to develop this machine entirely in house. Starting from a clean sheet design and utilising our extensive experience in
CAD modelling, drafting, FEA and fatigue analysis, electrical engineering, and PLC programming, we have total control over the development, and the continued evolution of the equipment,” says Ruari Soutar-Dawson. The main features include: n Radio remote control with pendant back up allows operators flexibility to closely observe working areas while still being in full control of the reline machine n Feedback screen provides crucial, real-time information to the operator n State-of-the-art electro-hydraulic proportional control system n Powered travel and rotation of the liner cart n Rail or tyre drive options, 4-wheel steering on tyre variants n Safety rated control components n Alignment camera system for grapple( optional).
In addition to 7-Axis Beam Mill Reline Machines, Outotec’ s offering includes other types of MRMs designed specifically for the smaller SAG mill and ball mill market, as well as full life cycle services for maintaining and optimising mills.
Tenova TAKRAF helps supercharge oil sands
Tenova TAKRAF has recently developed a symbiotic niche in the oil sands industry by giving both new and incumbent production trains the supercharged boost they need to sustain profitability in a low oil price environment. At the same time as boosting production, TAKRAF says it has achieved a recovery increase in the downstream extraction process; critically, this combined success has been proven during the
[ traditionally ] performance limiting Arctic winter months.
In 2013, TAKRAF was engaged by one of the principal oil sands producers to solve the winter period stalling of their incumbent Double Roll Crushers( DRC). The direct effect of the halt, as well as their restart inability, was significant cumulative annual restrictions on their winter production. So in 2014, TAKRAF began retrofitting all their primary crushing plants with the New Generation TAKRAF TRC 25.34 double roll crusher.
The TAKRAF New Generation DRC increased drivetrain inertia over 200 %, useable kinetic energy by 185 % and available motor torque by 168 %. This resulted in peak crushing demand dropping from nearly 600 % Full Load Torque( FLT) to a level near 350 % FLT. A specially designed motor with a Breakdown Torque( BDT) in excess of 430 % FLT was then implemented to deliver the full 350 % FLT through a larger capacity fluid coupling.
“ These changes represented a paradigm shift in the basic crushing principles utilised in an oil sands primary crusher. Previously, the technology primarily relied on expending its limited kinetic energy during every major crushing event, however, if the kinetic energy was completely expelled before the feed material was processed, the crusher would stall. Subsequent restart attempts were insufficient and often consumed the available heat capacity of the fluid coupling, further suspending the production recovery. The TAKRAF New Generation DRC possesses the ability to process the most difficult materials without primarily relying on consuming any kinetic energy; the inertial storage buffer translates directly to production guarantee.
The successful New Generation philosophy was then applied to the entire Primary Crushing Plant, two trains of which were put into production in 2016.“ The robust TAKRAF drive units and an abundance of surplus kinetic energy are already proven to process sustained tonnage rates exceeding 14,000 t / h, whilst maintaining an impressive 400 mm x 400 mm maximum product size – even when the feed approaches a 10:1 crushing ratio. At the same time, the TRC 25.37 is able to develop an impressive 11 % increase in the surface area of the product, significantly assisting the oil recovery process.”
The company adds:“ In the redesign of the oil sands Primary Crushing Plant, none of the components were ignored in the New Generation plant. Not just functionality and reliability being key areas of focus, but of equal importance were considerations for maintainability and reduction of downtime, during both planned and unplanned maintenance outages. The net result is the most effortlessly maintainable, cleanest and powerful primary crushing plant, which now
68 International Mining | MARCH 2017