Africa Mining Machine

Phillips Machine SA is a joint venture between Biz Africa, formed out of the Licence Mining group that has served South Africa's mining industry for the past half century, and Phillips Machine Service, a West Virginia, USA, based mining equipment company. For the past 27 years Phillips Machine Service has been involved in the maintenance and rebuilding of continuous miner equipment for room and pillar mining. In the course of its activities Phillips Machine Service recognised the value of the shuttle car as a low cost high volume haulage device, the technology of which has been proven over the last 40 years in coal mines around the world. These low cost operating features have been incorporated and enhanced in the design of the battery powered Freedom Car. In turn Biz Africa brings to the joint venture its expertise in developing new mining equipment products and successfully introducing these to South African mines. The company recently developed a new model roof-bolter, which has been widely accepted by the South African mining industry.

The Freedom Car, launched on October 3, 2003 at Biz Africa's new 4,000 m2 factory in Middleburg, is the result of a trend toward the use of industrial plate batteries in haulage devices, enabling the replacement of cable powered machines. Mining trials for a prototype 27 - 30 tonne payload capacity battery powered shuttle car will take place at Matla colliery. The Freedom Car is available in 12 - 30 tonne units, ranging from 1.1 to 1.6 metres in height and has a travel speed of 9.2 km unloaded and 7.5 km fully loaded. The Freedom Car can handle full-shift operation and its unconvoluted heavy duty frame construction ensures efficient throughput of ore.

The Freedom Car's motor controller incorporates the latest IGBT technology, and the batteries comprising Crown battery cells imported from the USA are built in South Africa under license to Biz Africa. The IGBT motor controllers allow for positive traction differential for four wheel drive, done electronically, and this ensures longer tyre life, improved manoeuvrablity and reduces roadway deterioration. The infinitely variable motor control on both traction and conveyor ensure the Freedom Car maximises its payload. Smooth acceleration, deceleration and creep speed reduces mechanical wear and shock on gear trains and brakes. The 37 kW traction and conveyor electric motors used by the Freedom Car are designed by Transvaal Electric of Johannesburg, and are interchangeable, reducing the need for extra inventory. Aside from the battery cells and controller technology the Freedom Car mostly consists of South African content. This ensures it is price competitive with other haulage devices, and at the same time it offers the potential to reduce operating costs by allowing greater productivity.

One of the major advantages of the Freedom Car, hence its name, is that it offers travelling route flexibility for shuttle cars in a continuous miner operation. A second major advantage is that it eliminates the inherent downtime of a cable shuttle car system due to cable damage. The Freedom Car also eliminates the potential for cable-related accidents where miners may be injured or worse.

In addition the Freedom Car offers significant advantages over other battery powered haulage technology. In the past decade a number of manufacturers have developed articulated battery powered haulers that have all their battery cells located in a compartment at one end of the machine, adding to the machine's length. This weight concentration on one end of the machine also unevenly distributes weight on the tyres. With articulated haulers having to turn frequently during a mining cycle, the additional distance travelled during a turning manoeuvre increases power consumption from the battery. The Freedom Car, which has the batteries centrally positioned – ensuring the vehicle's weight distribution is also well balanced – is designed to shorten the distance travelled during a turn and eliminate the number of turning manoeuvres required. With less distance to travel and fewer power consuming starts, the design of the Freedom Car's frame, which allows it to turn 90? within a 5.54 metre space, is very energy efficient. As a result of this and other advantages it is able to do the same work as competing technologies while using 20% - 35% less energy.