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24 www.coalage.com November 2018 dragline maintenance continued Cloud Peak Generates Compelling ROI with Synthetic Main Dragline Pendants Cloud Peak Energy installed the first set of synthetic fiber main boom pendants on its Marion 8200 dragline two years ago — with numer- ous benefits demonstrating a compelling return on investment (ROI), according to Applied Fiber. The first system recently completed the second annual inspection and shows that it is on track to far out- pace the life of steel wire in this rigorous application. With both an increase in production and substantial reduction in boom cracking, Cloud Peak Energy has since converted two additional draglines to Applied Fiber pendants. The main pendants support the massive boom and loading bucket on dragline. The conversion from steel wire pendants to synthetic fiber pendants has provided numerous financial and operational benefits — attributed to the dramatic weight advantage and dampening char- acteristics of synthetic fiber. These synthetic main boom pendants are made with Dyneema DM20 fiber, which is seven times stronger than steel wire rope at the same weight, providing exceptional dampening to system movement. The highly analyzed and engineered offering nearly mutes normal pendant and boom bouncing, addressing many historical issues with dragline boom fatigue. "This is not just a change of material, from steel wire to synthet- ic rope. These pendants are a productivity tool and have provided ad- vantages from day one. They have increased capacity of the dragline, reduced the stresses on the overall system, and provided numerous operational and financial returns that were not expected" said Jim Pumphrey, vice president of industrial products for Applied Fiber. Cloud Peak has wasted no time taking advantage of the benefits as they have recently outfitted two more draglines in their fleet with fiber main pendants. In fact, they retired a set of steel pendants two years early to realize the gains generated from Applied Fiber pendants. "Cloud Peak predicted and now has validated through actual performance an ROI in less than two years," Pumphrey said. "While no two mines or pieces of equipment are exactly the same, the returns and benefits are quantifiable. We have worked with our customers and industry experts to define the benefits of a conversion to synthetic pen- dants and developed an ROI calculator for our clients." In addition to reduced maintenance, elements such as increased payload, extended pendant life, deferred boom laydown, etc., are all considerations for the ROI calculator and help mine owners, maintenance and production managers make informed decisions." Applied Fiber manufactures the fiber pendants from a special- ized production facility, integrating the termination/end-fitting tech- nology with a production-testing process to ensure the pendant ropes are perfectly matched in length and tension to carry out this high load, high-cycle application. The test bed is 183 m (600 ft) long and has capability to tension and pre-stress pendants to nearly 950 metric tons or 2-million-lb tension. but the longevity and stocking fewer re- placement parts amounts to less money. The pads are the only replacement parts. "The time invested to make this change is minimal," Kallenborn said. "Maintaining several different types of brakes could take hours, where calipers are very quick." Ideally, Kallenborn would like to re- place the brakes on all the motions at once during the next planned maintenance event, but most mining companies opt to solve the glaring problems first. In the case of the mine that couldn't hold the swing motion, they were also having problems sourcing parts, Kallenborn explained. "They decided to take care of the swing motion first," Kallenborn said. "Now, they have budgeted brakes for the next time they service the drag and hoist motors. This rationale also applies to electric shovels." Another important fact to consider: There is no need to rebuild a Hilliard brak- ing system. "On some systems, there may be an occasional thruster issue and we just replace them," Kallenborn said. "With the calipers, it's routine pad wear. As long as the air gaps are checked routinely, there are no issues. Some mines assign that task to the electricians because they are al- ready looking at the motors regularly." "We have customers who haven't had to do anything on their brakes for five to seven years," Kallenborn said. "They in- stalled them and haven't given them a second thought." Kallenborn is passionate about the new Hilliard design. "We listened to our customers at the mines and incorporated those changes into certain aspects of the caliper design to make them more user friendly," Kallenborn said. Downtime on a dragline is very expen- sive. Now that markets have improved a little, maintenance planners are looking for efficiency upgrades to dig faster and move more overburden. Taking brake and motor maintenance off the table, they can focus their attention on other areas. These synthetic main boom pendants provide better dampening to system movement.