Are your statically stored gear reducers service ready? That’s the first of several questions from Dillon Gully of Motion Industries (headquartered in Birmingham, AL, motionindustries.com). He has good reason for asking. In conducting borescope inspections of statically stored internal-gear reducers for customers, Motion Industries personnel discovered as many as one-third of these assets sitting on shelves in a failed state.
Next questions: Are you willing to gamble the OEE (overall equipment effectiveness) and profitability of your facility on gear reducers and, for that matter, other capital spares that might not be service ready? What would you tell your boss if a critical spare were to fail within mere hours? Think this scenario doesn’t apply to you? How can you be sure? Gully offers some advice for achieving peace of mind.
— Jane Alexander, Managing Editor
Effective management of capital spares involves up-front identification of these assets and making sure they are in service-ready condition prior to preparing them for long-term storage. Unfortunately, many operations don’t follow through on this process once purchased units arrive on site. According to Gully, these steps are the only way to support the reliability of stored spares.
Capital spares can be defined as any item that is critical to production, promotes safety, decreases downtime, and/or prevents environmental issues. Gear reducers certainly qualify. The best way of verifying that these assets won’t fail as soon as they’re put into service is to inspect them before they are stored away—perhaps for years. Minimally invasive borescope inspections are a particularly good inspection method.
In a borescope inspection of a gear reducer, a camera scope visually inspects the condition of bearings, gearing, and internal components. The procedure can be accomplished through a plughole, which prevents contamination of an asset, if it is, indeed, ready for service. (Compared to the cost of replacing a failed bearing, costs associated with borescope inspections are also minimal.)
While information gleaned from borescope inspections can be used to confirm service readiness—or help identify steps for making a spare service ready—it can also help determine how to prevent these units from improper storage.
Corrosion, i.e., rust and contamination, are two, of many, causes of failure in gear reducers. When borescope inspections identify the presence of these failure modes, steps can be taken to correct them before the equipment is put into storage, as well as prevent those problems from recurring during storage.
Once a plan to prevent failures in stored spares is developed and implemented, it should be consistently followed. Every unit that will be stored, for whatever period of time, should be carefully protected. Preventing rust and contamination is a great start in protecting asset reliability and, thus, ensuring service readiness.
An ongoing process
Keeping stored spares in service-ready condition requires management accountability. Someone must be assigned responsibility for these assets, and expectations should be clear and realistic. It’s the responsibility of that designated person to ensure all spares are properly prepared and maintained. Identifying failed spares and bringing them back to service-ready condition is an ongoing process. As Dillon Gully emphasizes, “It should not be done one time and then forgotten.”
This plan for reliability can lower the probability of failure and bring a welcome degree of certainty regarding your stored gear reducers and other capital spares. MT
Working as an analyst for Motion Industries’ service center in Pensacola, FL, Dillon Gully has been conducting vibration and borescope inspections and managing capital spares for three years. For more information on these topics, visit motionindustries.com or bearings.com.