Published in March 2006 Australian Longwall Magazine

Using special software developed by CRCMining, researcher Bulent Tiryaki conducted the ACARP-funded project at Xstrata Coal’s Beltana mine.

The Cutting Head Performance Analysis Software (CPAS) can predict cutter motor power, ranging arm reaction forces, and vibrations for different drum designs, coal seams, and shearer operational conditions.

The work undertook to validate CPAS by measuring these parameters through an online data acquisition system.

This system, called Cutting Head Performance Monitoring System (CPMS), records the output of six strain gauge bridges, six accelerometers, and two pressure transducers on ranging arms during underground coal production.

Pressure data gathered from pressure transducers attached to the hydraulic cylinder supporting the ranging arm was used to calculate the actual vertical reaction forces.

The cutter motor power, vertical reaction force, and vibrations were then compared with those predicted by CPAS. The results of this comparison validated the pick force estimation model that was embedded in CPAS code.

As they are higher, vertical reaction forces are important indicators of the kind of cutting system required.

Further work has now resulted in the development of a second CPAS version that eliminates the need to perform coal cutting tests on the target coal seam. CPAS2 simulations for cutter motor power, vertical reaction force and vibrations were found to be close to those measured in the trials.

Tiryaki said the software could be used by longwall engineers for a range of purposes, including providing information to change operating parameters on a shearer.

“Using the software, you can choose to select a drum that will apply lighter loads on the ranging arms,” he said.

It is also expected to be a useful tool in planning future production levels and assessing the impact of changing various parameters.

“CPAS2 can be used to predict the cutter motor power, ranging arm vibrations, and reaction forces for a given cutting drum design in different Australian coal seams with small or no coal slabbing under a given set of shearer operational conditions,” Tiryaki said.

CRCMining has released the CPAS code, including fully functioning software code, on CD.

A new trial is being planned to measure strain on ranging arms and CRCMining is looking at the best position to place strain gauges.