HOISTING TECHNOLOGY
disconnects the control system’ s command to move the machine( motor torque) and have the brakes applied to stop the hoist safely and predictably. The unit also provides protection for additional pulley related protections, eg bad coiling, clutch monitoring( drum hoists), worn friction inserts, rope slip( friction hoists).
The Hoist Monitor is being designed as a compact, relatively inexpensive solution that can be retrofitted to most mine hoists to achieve greater functional safety. Once the Hoist Monitor is certified, it will feed into the development of the Hoist Protector, a more advanced system with additional controls, tailored for installation during a complete hoist system upgrade. The Hoist Protector will offer a complete solution for mine hoist safety, including all of the Hoist Monitor protections, shaft and underground level protections, eg gate monitoring, emergency stop push buttons. It will also provide a complete integration with the Brake System and variable speed drive’ s“ Safe-Torque Off” feature.
ABB has already created a site-specific Hoist Protector-style design for an Australian mine that pioneers the concept of the new system.
“ We have worked with ABB Sweden on a project-specific solution for a mine in New South Wales that takes into account most of the protections the Hoist Protector will deliver” Morey said.“ The engineering and site experience with this project will feed into the development of the Hoist Protector, continuing the close collaboration between ABB Australia and Sweden.”
Morey said ABB’ s third mine hoist system seeking SIL certification, the Brake System, was being developed in two parts.
The mechanical and hydraulic systems had already been designed and tested in Sweden; meanwhile ABB in Canada is developing the controller and electrical elements for the 2-4 channel SIL Brake System. Certification could occur as early as 2017 and ABB hopes to have the more complex Hoist Protector system SIL rated in 2018.
Morey said different elements of functional safety within the three systems could have different SIL ratings but ABB was aiming for the highest standards it believed possible. ABB is following the IEC 62061 standard for the development of these systems, which could potentially be merged with the parallel ISO 13849 to create a new international standard IEC ISO 17305. However Morey said any future change to the international standards would not greatly impact ABB’ s developments. New South Wales guidelines already include SIL requirements for mine hoists. Other states use a risk assessment based procedure to determine the required SIL of each safety function.
Thuthukani expands internationally
Following a drive to expand its reach internationally, Thuthukani Engineering was recently tasked with the design and drafting of the headgear, shaft collar and winder house for a new service shaft at the Philsaga Mining Corporation in the Philippines owned by Medusa Mining. The project commenced in 2015 and was carried out in cooperation with the Tech Edge Group which specialises in the production of winches and winders, and W J Engineering. Thuthukani provided the infrastructure design; Tech Edge was tasked with building the winder and W J Engineering fabricated all of the infrastructure components. According to Erik de Jongh, Technical Director at Thuthukani, this project has proven the mettle of South African engineering firms.“ We have proven that we can provide mining infrastructure to remote clients with minimal‘ hand holding’ needed.”
The infrastructure components were fully fabricated and tested in South Africa before being disassembled and transported to the Philippines for final installation. According to de Jongh the project rolled out smoothly and on deadline with few to no installation issues at the Philsaga site.“ All of the infrastructure components were delivered to and installed at Philsaga in mid-2016 except for the winder which was commissioned and delivered in early 2017. After being operational for several months we