Oyu Tolgoi is a large copper mine that has both open-cut and underground operations and has been operating since 2013. The mine is jointly owned by the Mongolian government and Rio Tinto and is located in the South Gobi Desert. Once fully operational, the mine is expected to produce 450,000 tonnes of copper annually.

The location of the mine in Gobi Desert means that operating temperatures can be extreme, from 45°C in summer to minus 35°C in winter. These operational conditions require careful selection of conveyor materials for robust and reliable performance. Martin Sprocket & Gear China have been working closely with the maintenance personnel at Oyu Tolgoi to improve the performance of their conveyor pulleys. With regard to pulley lagging, a number of ongoing problems have been identified and targeted for improvement:

  • Debonding of lagging from the pulley shell. This problem is seen with cold vulcanised lagging on replacement pulleys and is accentuated during operation at low temperatures where the loads on the bonding system increase with the increasing stiffness of the lagging.
  • Insufficient service life with rubber lagging on drive and non-drive pulleys due to wear.
  • Build-up of carryback on drive and non-drive pulleys that will result in belt tracking problems.

Martin Sprocket & Gear and Elastotec have been working closely to address these lagging problems and provide increased lagging service life.

In October 2017, Martin China applied Elastotec Hot Vulcanised Ceramic Lagging (HVCL) to two drive pulleys for Oyu Tolgoi. Both pulleys were installed in early December 2017 and were operational throughout the winter months with temperatures reaching minus 35°C. Pulley performance and lagging performance was unaffected by the low temperatures and maintenance personnel at Oyu Tolgoi indicated they were very happy with this outcome.

Following on from this success, Martin China recommended the use of the Elastotec Hot Vulcanised Polyurethane Lagging (HVPU) for a number of high tension non-drive pulleys. These pulleys had suffered from problems with localised debonding of lagging and material build-up due to carryback problems.

The Elastotec Hot Vulcanised (HV) bonding was a well-proven way to eliminate the debonding of the lagging. The use of polyurethane greatly increased the abrasion resistance of the lagging compared to rubber, while at the same time it provided resistance to build-up as a result of the much lower co-efficient of friction.

Once this recommendation was approved, Martin arranged for Elastotec to assist with the training and supervision of the application of the HVPU Lagging at their pulley manufacturing facility in Changzhou. In addition to developing the high performance HVPU Lagging, Elastotec have a detailed application procedure to ensure that the lagging performs exactly as designed.

Martin China have established a state-of-the-art pulley manufacturing plant in Changzhou and have invested in a PLC operated autoclave for applying hot vulcanised lagging. This state-of-the-art equipment allows Martin to control both the quality of the lagging application and the lead time.

The two high tension bend pulleys with Elastotec HVPU were supplied to Oyu Tolgoi and put into service in early 2018. Greg Fogo (International Bulk Material Handling Director for Martin) has visited Oyu Tolgoi to see the pulleys in operation and to obtain feedback from the site maintenance personnel. Current operation is as expected with no sign of the build-up or excessive wear problems experienced previously.

For additional information on the use of HVPU Lagging in critical conveyor pulley applications, please click here. Or contact:

David Molesworth
Sales Director Elastotec
Mobile: +61 423 200 178
Email: david@elastotec.com.au

Mariana Ballestrin
International Business Development
Mobile: +61 452 318 580
Email: mariana@elastotec.com.au

Greg Fogo
Group Manufacturing Director – China,
Martin Sprocket and Gear
Mobile: +86 186 2126 5962
Email: GFogo@martinsprocket.com