The Schramm T685W drill rig is mounted onto a Western Star 4900 chassis cab that was custom built to the requirements of the customer and the Schramm drill rig. The Western Star rigid has specifically been customised with numerous components that are common to both Western Star and Freightliner trucks operating in South Africa, so that it can easily be supported by one of fifteen approved Freightliner and Western Star dealers nationwide.
This special Western Star has been specified with three of the four axles on the truck being driven axles to provide outstanding traction when the truck is operating in difficult terrain as encountered on open cast mines. It has also been specified with an Allison RDS4500 six speed automatic transmission which makes the 35 ton mass of the vehicle easy to handle for an inexperienced driver even when running on steep inclines.
As an added safety measure the transmission has an integral hydraulic retarder which doubles up the margin of safety offered by the already powerful Jacobs Engine brake fitted to the Detroit Diesel Series 60 engine fitted to the truck. This approach of having a dual auxiliary braking system has been adopted to ensure safety when the rig is descending steep inclines into open cast mine pits.
The T685WS is the drilling contractor's rig of choice for mineral exploration, shallow oil and deep water well applications. Offering a pull back force of around 40 metric tons it is capable of handling a string of drill pipes up to more than 1km. Western Star Trucks is a brand of Daimler Trucks North America, and imported by Mercedes-Benz South Africa.
