dbt miner bolter notches up first six months
When DBT Australia bought Long-Airdox in 2001, it worked with United States designers to come up with a new machine that blended fresh engineering approaches with elements of the original Jeffrey design, known for its proven reliability.
"We began the re-design with extensive market research - we went to operators and asked what features were considered important, and what features they wanted in a miner bolter. Among others they listed ease of access for maintenance, better ergonomics and higher productivity," he said.
"For example, miner bolter cutter motors are traditionally located above the conveyor. The 30MB3 has been designed to allow the motor to be dropped into place through an access cover in the top of the cutter head frame - making it safer and quicker to install," said Scott.
Another maintenance feature is the ability to carry out all maintenance and component changes from either side without the need to remove other components to gain access, as opposed to from the top which requires the removal of the material pods and other structure.
The 30MB3 offers a totally integrated machine design with cutting, loading and bolting capability and operator comfort considered in the design, rather than drill rigs and operator platforms being an add on item to the core machine. Working with specialist drill rig supplier Hydramatic, DBT has improved the roof bolt positioning capability of the machine.
"A key roof control requirement with gateroad support is the ability to install bolts close to the centre line of the gate. We introduced a 12-degree chamfer on each side of the cutter head frame which allows the roof bolting rigs to be inclined inwards to install the bolts 250mm closer to the centre line on each side than the existing equipment utilised at Ulan can achieve. This means the distance between centre bolts is 500mm less than before," Scott said.
The hydraulic system utilises a load sensing variable displacement piston pump, which allows for simultaneous operation of all six bolting rigs and also reduces heat generation, creating a cooler environment for the operators, an important consideration for Queensland mines.
Each miner bolter that comes into Australia is sent in kit form, utilising common components including the cutter head and motors, centrifugal loading arms (CLA), and traction casing. The electrics, hydraulics and bolting equipment are fitted separately in Australia prior to delivery.
dbt wins first complete longwall package
The most pleasing aspect of the Glennies Creek longwall success was the tremendous global effort which resulted in this order, a company spokesman said. The shearer for example, will be built from stock sourced throughout DBT Global. With Consol (US) being a joint venture partner, DBT (US) had a major role to play in liaising with the key US based customer personnel.