Joy Global and CRCMining are working together to advance DynaCutTM technology by modelling performance across a range of rock properties. ODC (Oscillating Disc Cutter) technology has been licensed to Joy Global by CRCMining since 2006. At this time the technology was rebranded DynaCut and equipment development since then has been carried out by Joy Global. In 2011, Joy Global engaged with CRCMining and potential technology users to improve knowledge of fundamental rock breakage. It is intended that the Joy Global development team can use this knowledge to further improve equipment performance.
Joy Global has made substantial improvements to the operating performance and mechanical reliability of DynaCut technology since commissioning its test machine in 2013.
When the test machine Surface Rig 1 (SR1) was conceived in 2011, the performance of a single DynaCut cartridge in hard rock was in the order of 2 m3 per cutting hour with an average of 10 hours between breakdowns for the cutting device (cartridge).
Based around the chassis of a mid-sized roadheader the SR1 machine was developed for the purpose of enhancing DynaCut technology.
CRCMining Director of Industry Engagement Steve Powell, said the Joy Global team was intent on improving performance and reliability of DynaCut technology, but nobody predicted the level of success that has now been achieved.
Since 2011, many had pondered the future challenge of how to design a mine development machine with multiple cartridges and multiple booms. It was apparent that a number of cartridges would be required to achieve competitive excavation rates. It now seems likely that commercially attractive rates can be achieved with a single cartridge – creating substantial benefits for the application of such a simplified arrangement.
At the CRCMining forum, Brad Neilson from Joy Global outlined how the team are working together to advance the understanding around fundamental rock breakage mechanisms and what are the key rock properties that effect DynaCut performance.
“The Fundamentals of Rock Cutting project team are working with Joy Global’s full-scale cutting machine, applied to substantial rock samples, rather than laboratory scale,” he said.
Steve Styles, Hard Rock Mining Program Manager for Joy Global said, SR1 has demonstrated that a single DynaCut cartridge is capable of excavating igneous hard rock with instantaneous cutting rates in the range of 15 to 30 m3/h for a range of igneous rock types.
“The research team is applying robust experimental process to not only verify the cutting rates but also to analyse the rock properties in detail and relate these factors,” he said.
Tests on massive sandstone (nominally 80 MPa UCS) are achieving results up to 80 m3/h. Further tests will be conducted with sandstone in early 2016 with consistent experimental process as applied to the igneous rocks.
The image shows Joy Global’s DynaCut test machine, connected to CRCMining’s 80 MPa/250 litres/min pump system. This project was designed to examine the effects of high pressure water jets applied concurrent with standard DynaCut cutting action. Working together, Joy Global and CRCMining designed and implemented the experiment, culminating in the water jet assisted cutting trials undertaken in July and August 2015.
CRCMining has been working with Joy Global via several projects, co-funded by CRCMining, Anglo American and Joy Global.