Aggregates Manager Digital Magazine
Issue link: http://read.dmtmag.com/i/145964
inspection ritual. By comparison, when a household vacuum sucks dust through a compromised bag filter, dust fills the room. No one tolerates that in a house so the problem is quickly remedied, Replacing a complete fan is an expensive bit of resulting in no downtime, yet drillers might not notice the damage equipment issue. taking place at the fan caused by unfiltered dust. Outdoors, As the fan's blades unevenly deteriorate while though, a driller being sandblasted by the dusty grit, it will spin might tend to out of balance. An out-of-balance fan wears on tolerate it more, its hydraulic motor, causing it to leak oil. Left unchecked, the entire fan will need to be replaced. without realizing the damage that is taking place on the fan. Unfiltered dust sandblasts the fan's blades. As the blades deteriorate, the fan can start to spin out of balance. An out-of-balance fan wears away at its hydraulic motor, causing it to leak hydraulic oil. Replacing a complete fan is an expensive bit of downtime. Operators must inspect filters regularly, especially checking for water contamination in wet drilling conditions. A heavy, wet filter tears much more easily. 3. Keep coolers clean. Wentworth says his first five items were a challenge to prioritize. At times, pressure washing the coolers was at the top of the list because it's such a simple thing to do, yet so often gets overlooked or put off. It's definitely a top priority, though, because running fluids hotter than specified compromises their lubricating properties and is a primary cause of their breakdown. A rig's coolers must be regularly cleaned to allow them to control heat. 4. Drain water out of the fluids. Operators should routinely drain water from the diesel filter and both the hydraulic oil reservoir and the compressor, especially in hot climates. Atlas Copco advises its rig owners to drain water out of the compressor oil at least every other day, at a minimum. Water causes corrosion and, in cold climates, freezes up the valves. Lubrication properties are then compromised. Wentworth says some people blame equipment manufacturers when their hydraulics froze up, but it's almost always the result of operator negligence. 26 Water in the hydraulic oil reservoir can damage components in the hydraulic system and cause corrosion. It should be drained after the machine has stood unused, overnight for instance. During this time, water will settle to the bottom where it can be drained from a valve on the bottom of the tank prior to machine startup. Water must be drained from the primary diesel filter container daily. This is usually done by closing the fuel cock and opening the drain cock at the filter. 5. Grease the hoses. Wentworth said there are exceptions, but on most makes of drills, including Atlas Copco's, the hydraulic hoses attached to the rock drill run over a drum as they ride with the feed. Failure to maintain exterior lubrication of the hoses may cause chafing that wears off the hoses' protective covering. Using even the cheapest No. 2 grease available will preserve hose life. 6. Maintain rubber dust collector lining. Inside the dust collection system, a rubber lining acts as a shock absorber and deflector, protecting the collector's metal sides. If the lining were deteriorated or missing, it wouldn't take long for the high-velocity rock chips and fines to wear a hole through the metal. Since it's so expensive to replace a dust collector, Wentworth says rigs whose operators didn't maintain their rubber dust collection lining will often, instead, have a welded patch on the outside of the collector. Most of the time, it's only one patch because operators make sure to maintain the lining from then on, and there are no further problems. 7. Adjust the rock drill cradle wear slides. As a rock drill cradle's wear slides are worn down along the feed, they start to develop a little slop in their play. If not brought back to tolerance, the widening gap allows the hammer to wobble. The Aggregates Manager August 2013 EM_AGRM0813.indd 26 7/17/13 4:21 PM