A ‘Real-Time’ Approach to Maintenance Pays Off

There are many variables that make underground real-time mine maintenance an important matter. All of these surround the fact that the underground mining industry is ready for the paradigm shift from reactive to proactive maintenance. This article will look at changes in the manufacturing of underground mining equipment, the use of mature fleet management systems, the availability of on-board systems and the popularization of broadband networks. Also, it will examine the progress of real-time maintenance management in the open pit and factors that make the benefits of real-time mine maintenance “prime for the picking” for most underground mines.

When looking at underground equipment, the trend for more than 30 years has followed the evolution of underground mining methods. Just as methods have moved towards increasing tonnage throughput, underground mining equipment on average has gotten bigger. With an increase in payload capacity for extraction and haulage equipment, there has come an increase in capital and operating expenditures, along with a need to better manage these assets with more sophisticated and accurate tools. On-board sensor systems for the engines of underground mining machines have been in use for well over a decade. Today, the majority of large underground mining machines have sophisticated on-board systems, measuring everything from payload to the overall health of the drivetrain and hydraulic systems.

Another important and more recent development in the manufacturing of underground equipment is the rationalization of the vendors that deal in this space. Sandvik’s purchase of Tamrock and Atlas Copco’s buyout of Wagner are two big acquisitions worth mentioning, mainly because they have allowed them to standardize systems and components across equipment types.

Underground mines have long since standardized the use of one engine type. However, the unification of Load-Haul-Dump Loaders (LHDs), Trucks, Drills and Support Equipment under one original equipment manufacturer (OEM) has enabled other components, such as hydraulic systems and drivetrains, to be shared across the board as well. This is good from a technology standpoint, as it reduces the number of systems required to monitor and manage the fleet. Also, mines can now access on-board sensor information on smaller drills and auxiliary equipment. Prior to the aforementioned acquisitions, economies of scale would eliminate the existence of intelligent systems on smaller machines by specialist OEMs. The Elphinstone buyout by Caterpillar is also worth mentioning, as it has allowed the availability of Cat Data Link, Electronic Technician and even Vital Information Management System (VIMS) on underground equipment.

When considering the use of technology to manage fleet maintenance, real-time monitoring of on-board sensor data (telemetry) may not always be the most cost-effective approach. But several mines in the world can benefit from fleet management systems, and by leveraging position tracking and real-time capabilities they can significantly improve equipment utilization and availability. The handover from mining to maintenance is always a problem. Finding underground equipment after it has broken down or parked up for a Preventative Maintenance service can also be a laborious task for maintenance staff and production managers. Underground fleet management systems solve this problem, and they are also a good foundation for real-time mine maintenance.

As mentioned, engine management systems have been in use underground for well over a decade. On-board sensor systems that monitor payload, drivetrain, fuel level and the health of hydraulic systems have also been available for some time. The need for remote controls underground has pushed on-board systems to automate all aspects of equipment operation. Today, most underground OEMs have drive-by wire capability over a CAN bus, which facilitates the work required by makers of remote control devices. This capability also provides unique opportunities for condition-based monitoring of equipment. And while OEMs have long provided these sensor systems in some form, the technology has evolved to a state where real-time underground mine maintenance can be justified.

It is important to point out that interfaces provide important information to a fleet management system. From production tracking to fueling monitoring, the value of integrating raw, on-board sensor data should not be overlooked. Simple problems often plague underground equipment, such as the reliability of a physical gauge that displays a certain level or pressure. The reliability of the electronics of many on-board systems has actually surpassed that of physical gauges. When looking at interfaces, mines should consider the simple, pragmatic solution that on-board sensors provide: an alternative for operators to monitor operational parameters.

The idea of telemetry has been in existence for some time. The most basic concepts of real-time mine maintenance require real-time connectivity to various equipment sensors. While low-level sensor data has been available, what has been missing in the underground mining industry is the wireless network bandwidth to access sensor data remotely. Today, most providers of underground wireless communication systems offer a broadband (high bandwidth) solution. Whether this is via traditional Wi-Fi Access Points, Radiating Cables, or MESH algorithms, the technology is available and proven. Yet the business case and value proposition to actually pay for the extra bandwidth are absent-mainly because, in the last decade, the industry has been focused on the voice communication problem.

Voice-Over IP handsets and telephony features have often been published in the media under the topic of underground broadband networks. The use of these products for control and instrumentation of remote fixed systems, and the ability to perform “telemetry of equipment vital signs,” has been the advertising slogan of several technology companies. But what most mines are realizing is that getting the data across the office is not enough. What is needed is an application that actually facilitates real-time mine maintenance. Simply providing bandwidth and data does not deliver on the value proposition of real-time and predictive mine maintenance. Overall, the profitability of an operation is dictated by grade and production throughput, and then cost per ton. For profitability to increase, costs must decrease, and the cost of purchasing a broadband network needs to be offset by savings elsewhere.

As a solutions provider to the mining industry, Modular Mining Systems, Inc. has solved the real-time mine maintenance problem. First released in 2002, the MineCare® real-time mine maintenance system is now actively reducing maintenance costs in over 40 open-pit mines around the world. The MineCare system’s ability to provide a positive ROI on the installation of a broadband network has been proven in the open pit. And with the release of the PTX underground mobile platform, the benefits of real-time maintenance are now available to underground mines. PTX supports both the DISPATCH and MineCare applications using the same mobile computing platform.

There are many mines that make the installation of a fleet management system dependent on a wireless communication upgrade. However, at Modular, we recommend installing a fleet management system on the existing wireless communication system first. To achieve this PTX has maintained its ability to talk over Leaky Feeder networks. By institutionalizing some real-time mine management practices such as those discussed in this article, a mine can build its capability to demonstrate improvements in the bottom line. Once a fleet management system such as DISPATCH is in use, the payback for a capital expenditure for an underground broadband network will be simple to achieve. By performing predictive maintenance with a tool like MineCare, mines can achieve a short payback period on their wireless upgrade by a predictable and achi
evable reduction in maintenance costs for their mechanized fleet.

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Information for this article provided by Stephane Cantin, Product Manager, Sales and Marketing, Underground, Modular Mining Systems Canada, Ltd.