INDONESIAN mining company Bukit Asam is expanding its coal operations at Tanjung Enim Mine in Sumatra, Indonesia, and is continuing to rely on TVVS fluid couplings from Voith. For 10 new belt conveyors at Tanjung Enim, Bukit Asam deploys 14 TVVS fluid couplings from 55-315kW.

In the past, the mine operator has always been pleased with the reliability of its already installed Voith fluid couplings which ensure smooth start-ups day after day and a long service life for all components, especially the belts.

“We’re all very impressed with the performance of the TVVS constant-fill fluid couplings. They’re very easy to maintain - only oil changes are needed - and the reliability is just great,” says Bukit Asam’s manager of maintenance planning Kris Tjahajaning Tyas. The mine operates 24/7 and any equipment downtime means loss of production.

In older sections of the mine they’ve been using TVVS on belt conveyors since 1997 without any unplanned downtime. “Proven reliability is why we absolutely wanted to have Voith fluid couplings in the new conveyor drives as well,” adds Bukit Asam’s senior manager of maintenance Tatra Muis.

Voith says its fluid couplings are well suited for use in extreme environments and are completely insensitive to harsh conditions like dust, dirt and humidity. The fine coal dust in Tanjung Enim mine has no effect on performance. The couplings dampen torsional vibrations in the driveline and protect it against overload, extending the life of the entire system. Because torque is transmitted by a fluid, the power transmission of the fluid couplings is wear-free, reducing maintenance to a minimum.

Bukit Asam’s maintenance managers are happy with the many benefits the fluid couplings provide. They also appreciate the advice and after-sales support from the local Voith team, along with unmatched know-how on the entire drive system.

The 13 existing belt conveyors in the Tanjung Enim mine still rely on TVVS fluid couplings (rated from 55-500kW) installed more than 17 years ago. The mine has two coal handling facilities with the longest belt conveyor being 4284 metres-long and an hourly capacity of 1700 tonnes. The drive of this conveyor is equipped with three 315kW motors and three fluid couplings, type 750 TVVS. In addition to the conveyor drives, the bucket wheel excavator drives in the mine are equipped with five 750kW fluid couplings, Type T, that dampen vibrations and protect the driveline from damage also in case of frequently occurring overload.

Tanjung Enim Coal Mine is one of the largest coal reserves in Asia. It has been in operation for more than 90 years and in 2012 produced nearly 15.5 million tonnes of coal with the production forecast even higher in coming years.