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CRANES AND RIGGING 36 E&MJ; • JULY 2017 www.e-mj.com Other manufacturers are incorporating features from different types of cranes to offer models suited to mining's often unique set of requirements. Liebherr, for example, exhibited at last year's MIN- Expo trade show the LTR 1100, which combines the advantages of a telescop- ic crane with those of a crawler crane. This, said the company, makes the model highly suitable and useful for operations on mine sites, because the crawler travel gear provides excellent off-road handling and maneuverability. The crane, claimed to be capable of moving loads with great precision, additionally offers telescopic crane-related benefits such as shorter setup times, simpler transport and the variability of its boom system. The LTR 1100 features a telescopic boom of 171 ft (52 m), has a lifting height of up to 272 ft (83 m) and a radius of up to 195 ft (60 m) with lattice boom jibs. The ability to maneuver in muck doesn't apply just to cranes used in sur- face mining activities. Late last year, Manitowoc reported that PT Freeport In- donesia added three Grove cranes to its fleet. The RT765E-2 and two RT530E-2 rough-terrain cranes join the company's operations at its Irian Jaya location, one of the world's largest mine sites. The new units will replace two older Grove RT cranes that are being retired. The three new cranes will be applied primarily in underground expansion, where they will be used for steel erection work, and in supporting mill shutdown work or other tasks around the site. "The RT cranes are the per- fect size to operate in the un- derground environment and to support shutdown work around the mill area," said Jason Smith, who works in mobile crane maintenance for PTFI. The RT765E-2 has a capaci- ty of 60 metric tons (mt) and includes four-wheel multi- mode steering and a Full Vi- sion cab. The RT530E-2 is a 30-mt capacity unit with a Tier III compliant 119-kW (160 hp) QSB 6.7L Cummins diesel engine. The crane also includes CCS, plus dual-axis electric joystick controllers. "Compared to the older models, the initial crane setup is much easier, and therefore, getting the cranes to work is much faster. There are more options for slew limits and boom angle limits," Smith said. "More importantly, it's much easier to diagnose any faults with the software, so downtime is minimized, too." Manufacturers are also unveiling inno- vative lifting gear for applications in which a crane may not be needed or available. Enerpac, for example, recently introduced its SL300 hydraulic gantry, the company's latest model in the SL series of telescop- ing hydraulic gantries. Equipped with two- stage lifting cylinders, the SL300 lifts up to 22 ft at the top of the second stage and can handle up to 337 tons in the first stage. Designed to meet stringent safety re- quirements, the SL300 complies with standards set by ASME B30.1-2015. The SL300 is also CE-compliant. Stopping the Drops The potential impact from a crane accident can be catastrophic in terms of cost, damage and injury. However, smaller mishaps due to dropped tools and other items by workers overhead are much more common. Each year across the U.S., more than 50,000 recordable incidents involving workers "struck by fall- ing object" are reported, according to the U.S. Department of Labor Statistics. That represents one injury caused by a dropped object about every 10 minutes, and OSHA has calculated that the average direct cost to an employer for a lost time injury such as a contusion resulting from being struck by a falling object is more than $27,000. Tool restraint accessories are available from a number of sources, such as Proto's Tethered Tool System, which employs heat shrink loops, tool collars and sealing tape with D-Ring web tethers to transform existing tools into tether-ready versions. Ac- cording to Proto, with just a few simple steps, various wrenches, hammers, screwdrivers, punches, chisels, and hex keys can be retrofitted and used safely at height, or in work areas requiring foreign material exclusion (FME). But what about the fasteners those tools are used with? A new tool has been developed by RToddS Engineering (rtodds-eng.com) to help reduce incidents of dropped fasteners and the related costs. The Washer and Nut Keeper is a flexible rubber socket set that can be loaded with any combination of nuts, bolts or washers of a given size. Once loaded, the fasteners stay in the flexible socket and in perfect alignment for starting them either in a tapped hole or on a stud or bolt. The flexible socket has ribs for easy gripping. Once the fastener stack is started, the Washer and Nut Keeper is removed and final torque- ing is done with conventional sockets or wrenches. Each socket is designed with a series of cavities that securely hold the fasteners in place, and the base has an opening for a standard ratchet drive or extension. A Washer and Nut Keeper can be designed for any combination of standard, metric or spe- cialty fasteners. Liebherr's LTR100 crawler crane, equipped with a telescopic boom, has a lifting height of up to 272 ft and a lift radius of 195 ft. Like all Enerpac gantries, the new SL300 has self-contained hydraulics and electronic controls.