Manufacturers explore options for the untethered workhorses of the room-and-pillar mine
By Steve Fiscor, Editor-in-Chief
Rubber-tired haulage plays a vital role underground, shuttling coal from the continuous miner to the feederbreaker before it’s fed into the mine’s conveyor network. Those haulage options include tethered shuttle cars and untethered scoops that can be either battery- or diesel-powered.
Beyond their duties in the continuous miner sections, they also improve efficiency and productivity throughout the mining process. Scoops are used for cleanup at the dump point and face, road repair, supply deliveries, assisting in maintenance operations, and much more.
Gainwell Relaunches the 488
In December 2021 Gainwell Engineering acquired the intellectual property related to Caterpillar’s line of scoops. The company recently relaunched the product line, which includes the former Cat 482, 488, 488L, 488XL, 488-6, in battery- and diesel-powered configuartions.
The product line ranges from the 482 with a 28-in. height to the 488-6DM with a lift capability of 16 tons. The gross vehicle weight starts at 42,000 lb (with a battery) and increases based on the machine model.
The battery-powered options include single or dual 120-v DC tram motors or a 240-v AC motor with a variable frequency drive. There is also a diesel-powered version. The machines are available with 4-wheel drive axles and reducer mounted emergency brakes, or SAHR equipped axles with superior braking and differential durability.
All 482s and 488s provide ground-based battery changers, allowing the machines to engage and lift their batteries from well below grade. The oscillating center section allows the vehicles to keep all four wheels on the ground in uneven terrain for maximum traction. These scoops were also the first to adopt a combination of high-strength steel with appropriate welding techniques, Sizemore explained.
“We are doing some innovative things with these machines to adapt to different and everchanging applications, like offering a variety of different front-end arrangements such as load haul dump (LHD) style buckets to quick-attach implements to fit
the end user’s needs,” said Jason Sizemore, general manager, Gainwell Engineering. “The LHD style front-end gives the operator more overall vertical lift along with the lift-tilt function to keep the load level and stable.”
Gainwell is building a new major manufacturing plant in India, where the company is headquartered. “The first phase is complete, and the company just commissioned it,” Sizemore said. “The first pieces of mining equipment are coming off the new production lines now.”
Scoop manufacturing for North America, however, will remain in West Virginia. “We are producing several scoops, which are heading to a coal mining operation in Canada,” Sizemore said. “These will be the first new Gainwell-branded scoops.”
Gainwell also brought Jim Coe back on board. “Coe was heavily involved with the design of the 488s, and the 636s, and he also designed the 650 and 680 Shield Movers,” Sizemore said. “He and our entire engineering staff have been instrumental in helping us with this relaunch, especially as far as re-establishing the supply lines. With the entire team’s expertise, we have found replacements for components that were no longer available, whether it was a simple item or a complex electrical motor drive. We’re working with new suppliers and exploring many different avenues to enhance the product line and the overall customer/operator experience.
“The entire process from start to finish is complicated, but with the experienced team we have at Gainwell we are looking forward to offering these machines to the mining market,” Sizemore said.
Gainwell will have a stand at MINExpo, but they will not have equipment on display. “Unfortunately, it will just not work out with our current manufacturing schedule,” Sizemore said. “The machines are shipping to market as fast as we can build them.”
The Versatile Un-a-trac
At Simmons Equipment Co. is proud of its long history, supporting and producing equipment for the underground coal mining industry. The company’s founder, Jack Simmons, embarked on his career in 1963 with S&S Mining Machinery, where he played a pivotal role in leading it to become the global market leader in battery-powered underground mining scoops.
Building on this history of innovation, Simmons now produces industry-leading equipment for the mining industry that meets global, federal, state, and local regulatory standards, with approvals from MSHA, ATEX, IECEx, DGMS, Pennsylvania, and others. Paired with its innovative culture, the company has an unwavering commitment to quality. It now produces all its OEM products with superior quality control systems, with ISO 9001:2015 and IEC/ISO 80079-34:2020 certification achieved in 2023.
The Simmons Un-a-trac product line offers both state-of-the-art battery-powered scoops and diesel-powered scoops to best serve our customers.
Simmons Un-a-trac scoops are versatile. They are found in many U.S. room-and-pillar operations, as well as globally. More recently, the company’s battery-powered scoops have increasingly been used in support roles for longwall mines.
Simmons said the Un-a-trac scoops set the bar in performance, safety, unique features, design, operator comfort, operator control options, and maintenance-friendly designs, incorporating advanced innovative technologies.
Safety is the company’s No. 1 focus. Recently, Simmons received the Mine Safety and Health Administration (MSHA) Innovation award from the National Institute of Occupational Safety and Health (NIOSH) for significant advancements in enhancing mine safety. This was achieved by applying technology or improved processes in innovative ways, particularly in enhancing safety features on the S360 scoop.
When combining the overall versatility of a Simmons battery-powered scoop with AC motors and the Simmons DC-AC inverter control system, the result is a machine optimized to work in the most demanding underground conditions. The DC-AC inverter control system allows for more load per shift, greater torque across the entire operating range, better hydraulic system performance, reduced downtime, and more efficient battery charge cycles. Additionally, AC motors have a distinct advantage, requiring less maintenance and offering longer life expectancy between rebuilds.
The scoop could also be manufactured with an advanced diesel engine, torque converter, and engineered mating power shift transmission package for optimum performance and maximum torque. The Simmons diesel-powered scoop offers many of the same interchangeable and advanced options from the battery-powered scoop product line.
The Un-a-trac scoop line features a high-strength, robust steel-fabricated main frame, a heavy-duty oscillating ball bearing center section, heavy-duty axles with spring applied, hydraulic release braking system, ergonomically friendly operator machine controls, a ground-level battery change system, varied wheel and tire options, and an industry-leading electrical and hydraulic system. The model lineup is configurable to operate in any seam height, offering numerous options for tailoring each unit to its unique application.
The Simmons engineering staff has more than 200 years of combined experience in the underground mining business. Using advanced engineering tools, our dedicated engineers are actively engaged in advancing our underground mining product lines to the next level through research, development, and testing. Product improvements include using the very latest technologies, such as advanced materials, software optimization, improved motor designs and control techniques, advanced motor field-weakening for improved performance, enhancing structural designs, simplified control systems, hydraulic system optimization, improved machine efficiencies and shift life, reduced maintenance time and downtime, and enhancing onboard diagnostic information, all with the focus of optimizing safety and performance.