The Challenge and The Solution
Supported by a technology transplant from the leading bearing supplier Schaeffler Australia Pty Ltd, KCMG Pty Ltd has reduced tube mill maintenance and expensive breakdowns.
Schaeffler Australia supplied KCMG with custom-fabricated sliding sleeve housings and FAG spherical roller bearings, for tube mill processing of output from KCMG’s Kalgoorlie gold mines, including the Fimiston Open Pit (Super Pit) mine and the Mt Charlotte underground mine (Figure 1). This allowed KCMG to eliminate downtime costs of over $A45,000 ($US 33,000) per hour. Over 800,000 ounces of gold is produced from Mt Charlotte and Fimiston every year, making the mines one of the top 10 gold production operations in the world.
Figure 1. Schaeffler sliding sleeve housings and FAG spherical roller bearings are widely applicable to tube mills
The Challenge and The Solution
In the mines, the tube mills are exposed to high temperatures during the day and low temperatures at night. Previously the tube mill had a sliding base housing at the floating bearing location, but bearing failures were happening annually, which resulted in a disruption of production for several days.
Schaeffler’s package of spherical roller bearings (Figure 2) and sliding sleeve housings means that floating bearing displacement takes place between housing bore and sliding sleeve, rather than housing and sliding plate. Lubricant is constantly applied between the sliding sleeve and housing bore to ensure a low coefficient of friction when thermal expansions occurs inside the 7,000 mm long, 3,000 kW tube mill with a speed of 14 U/min (when load acting on locating bearing is 1,600 kN and load acting on floating bearing is 1,800 kN).
Figure 2. FAG spherical roller bearing
Due to the new bearing arrangements bearing failure does not occur annually, and downtime is reduced, enabling KCMG to increase its production. With the Schaeffler solutions, shutting down the facility for up to two days at a time to replace damaged bearings is completely avoided. As a result, the customer is able to save an average downtime cost of roughly $A45,000 per hour.
According to Mr Martin Grosvenor, Industrial Sector and Product Manager at Schaeffler Australia, sliding sleeve housings are a reliable and field-proven design for grinding mills. These housings have been specially designed to be used in mining operations, and can be employed for these machines. Schaeffler group’s premium quality FAG roller bearings provide continuous and reliable service to customers.
Schaeffler bearings are supported with the company’s installation expertise, product selection and packaging solutions, lubrication technology for optimal performance, and online condition monitoring.
According to the company, the Schaeffler X-Life bearings are produced with cutting-edge manufacturing technologies to achieve a better and more homogeneous surface over the entire contact surface between the rolling element and raceway.
Under similar operating conditions, the service life of X-life bearings is significantly longer than standard bearings. It is possible to increase the operating loads for the same service life as before. With over 82,00 people across the world that include over 6000 employees at 16 research and development centers, Schaeffler is committed to deliver high-performance, low-maintenance bearing solutions.
This information has been sourced, reviewed and adapted from materials provided by Schaeffler Australia Pty Ltd.
For more information on this source, please visit Schaeffler Australia Pty Ltd.