This conveyor is equipped with three 750 TVVS fluid couplings (pictured above).

The Indonesian mining company Bukit Asam expanded its operations at the Tanjung Enim coal mine in Sumatra, Indonesia. For 10 new belt conveyors, it will deploy 14 TVVS fluid couplings from 55-315 kW.

“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,” said Kris Tjahajaning Tyas, manager of maintenance planning for Bukit Asam. 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,” said Tatra Muis, senior manager of maintenance for Bukit Asam.

The Voith 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 has had no effect on performance. The couplings dampen torsional vibrations in the driveline and protect it against overload, extending the lifetime 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.

The 13 existing belt conveyors at Tanjung Enim still rely on TVVS fluid couplings (rated from 55 to 500 kW) that were installed more than 17 years ago. The mine has two coal handling facilities, with the longest belt conveyor having a length of 4,284 meters and a capacity of 1,700 tons per hour. The drive of this conveyor is equipped with three 315 kW motors and three fluid couplings, type 750 TVVS. In addition to the conveyor drives, the bucketwheel excavator drives at the mine are also equipped with five 750 kW fluid couplings, Type T, that dampen vibrations and protect the driveline from damage also in case of frequently occurring overload.

Tanjung Enim coal mine, located in Sumatra, is one of the largest coal reserves of Asia and the world. The mine has been in operation for more than 90 years. In 2012, it produced nearly 15.5 million tons of coal, and the production forecast is higher in the coming years.