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MAINTENANCE Maintenance is Key for Breakers In recent years, hydraulic breaker technologies have evolved rapidly to include advancements that not only optimize break‐ ing efficiency and reduce operating costs in mining and aggre‐ gate applications, but they help minimize downtime on the job. While performance of a breaker has traditionally been meas‐ ured by the tons of rock per hour, said Stephane Giroudon, Doosan strategic account sales manager, a breaker's cost‐per‐ ton is quickly becoming the industry standard. One of the easi‐ est ways to keep your tool's cost‐per‐ton ratio low is to identify technologies that help reduce the effects of the con‐ stant beating breakers take in the high‐psi conditions associ‐ ated with mines and quarries. Additionally, there are also some key best practices that can contribute to the extended life of your attachment and your excavator. A significant technological improvement for breakers in min‐ ing and aggregate applications is blank firing protection de‐ signed to guard the hammer from extra wear and tear when an operator misfires. Standard on leading manufacturers' rock breakers, the anti‐blank‐fire protection employs a hy‐ draulic cushion at the bottom of the cylinder bore to dampen the movement of the piston. It also protects the hammer against metal‐to‐metal contact, decreasing the premature de‐ terioration of the breaker and its bushings, retaining pins and front guide. Some manufacturers offer an energy recovery valve in the hammer that can add performance in hard material. Increas‐ ing a tool's strike power by using energy generated by piston rebound, the valve recycles recoil energy and transfers it to the tool's next blow, increasing striking power. Another key advancement in breaker technology is speed con‐ trol. When a hammer's stroke can be adjusted, operators can match breaker frequency to material hardness. This provides greater productivity and reduces the amount of harmful en‐ ergy transferred back to the excavator. Rock-Solid Maintenance As with any piece of equipment, proper maintenance is critical to operational efficiency, productivity, and most importantly, life span. While excavator‐mounted breakers are used in some of the most punishing conditions, some simple steps can be taken to mitigate premature wear on the tool and the machine. Although some manufacturers include wear indicator devices www.rockproducts.com with their tools, it's critical to inspect key wear points on a daily and weekly basis. To increase uptime, field re‐ placeable wear components like bushings and re‐ taining pins can provide perform‐ ance solutions within minutes. While the breaker's nitrogen level needs to be recharged peri‐ odically according to a manufacturer's specifications, greasing is a process that must be done multiple times on a daily basis. Giroudon advised a sharp focus on lubrication: "A grease sta‐ tion is a must for a quarry operation." Typically, a cradle‐mounted and/or an excavator‐mounted lube station is available for some breaker systems. "For a quarry operation, I recommend the excavator‐mounted option with a bigger grease capacity because it takes less refill inter‐ vals. The cradle‐mounted approach is good when you need to mount the breaker on different machines," Giroudon said. Giroudon recommends the following additional breaker/exca‐ vator tips: ■ Make sure you grease the tool/bushings frequently with the proper grease. A No. 2 lithium‐based grease with 3 to 5 percent moly rated to exceed 500 degrees F is ideal. ■ Move the tool and reposition often. If the hammer runs for prolonged periods, drilling will occur. This will cause ex‐ treme heat and premature failure. ■ Use the right tool for the job. Contrary to popular opinion, the blunt tool is best for most oversize breaking, as it pro‐ vides better positioning and better transmission of the shockwave. ■ Avoid blank firing. This is the most abusive action for a breaker. The smaller the rock, the greater the chance of a blank fire. Outsmart the rock by stopping the hammer be‐ fore it fires through the material. A variable‐speed hammer should be considered to reduce the transfer of damaging energy back to the breaker. E Source: Doosan ROCKproducts • AUGUST 2012 53