Aggregates Manager Digital Magazine
Issue link: http://read.dmtmag.com/i/718149
28 AGGREGATES MANAGER / September 2016 MINE MANAGEMENT stratifi cation of material, lower bearing life, or premature breakage of body components due to improper operation. In the end, this leads to unscheduled downtime, contaminated product, or the required tons per hour not being produced. Call for backup Custom fabrication shops can't offer the support benefi ts of the original equipment manufacturer. OEMs usually have the infra- structure to ensure effi cient problem solving. If there is a prob- lem with a part, a reputable OEM will take full responsibility, quickly assess the situation, and promptly send a replacement. Most parts shops don't have the resources for a quick, precise turn-around if the part doesn't work right, and there is no guarantee the replacement fabricated part will be correct. In addition, working with an OEM means having a sup- port team that understands an operation, its production, and equipment. They know what parts will wear quickly and what parts need to be on hand to limit downtime. They often offer OEM supplier agreements that ensure they will have critical parts in stock for immediate delivery, limiting or eliminating extended downtimes. OEMs' focus on vibrating screens also brings an in-depth product knowledge that's rare elsewhere. Some manufactur- er's certifi ed technicians test machines as a system before each leaves the factory, and they run the same tests once the vibrating screen has been commissioned to ensure results are identical. They use this information to make sure every com- ponent is running at OEM standards. In addition, the machine and components are backed by a strong warranty program. Not only do some manufacturers offer warranties on new equipment purchases, some guarantee parts for up to a year if an operation uses OEM-certifi ed technicians and parts and performs regular maintenance. Any fabricated parts introduced to a machine during a warranty period will void the entire machine warranty. Fabricated parts' hidden price tag While at fi rst a fabricated component seems to make sense because it can often cost less than an OEM part, those savings are often short term. Minor imperfections in the part or lower tolerances for the stress placed on the machine can cause the component to fail prematurely, resulting in additional replace- ment costs on top of unscheduled maintenance. Even while the part is functioning, it often adversely affects the produc- tion of the machine, diminishing the throughput and limiting profi t potential. But the potential damage from an imperfect part doesn't stop there. Those imperfections could start a chain reaction that leads to the damage of a series of other parts. This is especially true for shaft components, which form the heart of a vibrating screen. For example, if the shaft shoulders are not machined within the OEM tolerances, an operation could see problems within hours of operation. This slight difference in size can cause the shaft assembly stack up to be too tight or too loose, leading to excessive heat and or wear of the shaft components. This can cause bearing failure or premature breakage of shaft components or body components. This chain reaction of issues could result in maintenance costs far greater than the price of the fabricated component, but the cost is compounded by the fact that rarely is the heart of the problem diagnosed on the fi rst pass. Most operators miss the true cause of the problem and begin fi xing the symptoms — a cracked panel, a cross member, or sections of screen media. Then the damage is destined to repeat and those parts must be replaced again. These symptoms might become obvious within 48 hours; while the root cause might take a month before it's realized. By the time technicians fi nd the issue, the cost of the initial part fi x could be greatly multiplied and could be much higher than what the OEM counterpart would have cost. Take tension rails, for example. A customer might wonder why his screen media is breaking after just a week of use, Fabricated tension rails, if not built to original equipment manu- facturer tolerances, may not correctly tension screen media. This could lead to broken screens and thousands of dollars in new screen media and downtime before the operator realizes the problem. Manufacturers design and build vibrating screens as a total system. The weight of the parts, required running speed, and amplitude are all taken into consideration when balancing the machine.