Use aviation-style checklists to eliminate ambiguity and errors in your lubrication-maintenance procedures.
By Ken Bannister, MEch Eng (UK) CMRP, MLE, Contributing Editor
Arguably, the most used and abused instruction in the field of practical lubrication is “lubricate as necessary.” The origin of that advice is often attributed to the OEM’s (original equipment manufacturer’s) machine operation and maintenance manual.
OEMs typically prefer to use subjective language when outlining a maintenance approach in their manuals. As a consequence, they rarely provide accurate lubrication instructions based on the ambient condition factors found in the end-user’s working environment. This is especially true when the OEM sells its equipment globally through third-party agencies and retains little control—or understanding—of how and where that equipment is used. The level of subjectivity is further amplified when an unsuspecting and/or unenlightened maintenance-department person follows, without question, the unaltered written instructions.
A key component in reliability and performance improvement—with regard to maintenance personnel and machines—is consistency of effort. This type of consistency is afforded through an understanding in two major areas:
- the impact that a current operating environment has on machinery requirements
- who, exactly, performs lubrication tasks.
The highest level of reliability possible with any machine is primarily achieved as a result of the simplest of maintenance observations and tasks, based on the equipment’s weakest links. A machine’s weak links typically present themselves in two formats: consumables and adjustables. Often thought of as “nuisance” or “pain” points, weak links are instantly identifiable systems or components of an equipment system that require regular or constant replacement or modification. Lubrication falls into both of these categories.
Recognizing your work environment
Lubricants are considered consumables because of their propensity to leak out of a closed environment or deteriorate in service, thus requiring replenishment or full replacement. A machine’s working environment can dictate how quickly the lubricant will deteriorate. For example, a bearing operating in an extreme wet, damp, hot, or dirty environment, similar to that in a foundry, mining operation, or steelmaking operation, will call for a more intensified approach to lubrication management than bearings that are operating in “white-room” HEPA-filtered environments such as those found in pharmaceutical-manufacturing operations.
Lubrication-delivery systems also require monitoring to determine application requirements and schedule adjustments based on changing needs. For example, using a manual greasing approach in bearing lubrication will require a change in PM (preventive maintenance) frequency when moving from a single-shift to double-shift operation. Similarly, in changing to an automated lubricant-delivery system, note that the lubricant reservoir will likely require replenishment at twice the previous (manual) rate and necessitate an adjustment of the lubricant-fill cycle.
Recognition of your working environment, and tailoring your lubrication approach accordingly, is the first step to implementing a “lubrication by design” method and, ultimately, achieving true lubrication effectiveness.
Objective instruction and interaction
Instructing an operator to “lubricate as necessary” will only guarantee a subjective decision about which lubricant is to be used, as well as how much and how often. Subjectivity, in turn, invokes inconsistent behavior leading to lubricant cross contamination, over or under filling reservoirs, bearing-seal breaching, or starving bearings. These situations all reflect high-risk behavior that can easily result in premature, yet preventable, machine failure and downtime. They don’t have to be a problem in your plant.
In Dr. Atul Gawande’s 2009 best-selling book, The Checklist Manifesto: How to Get Things Right (Metropolitan Books, New York), he described the first military test flight, more than 75 years earlier, of the Boeing B17 bomber that had been introduced in the late 1930s. Ending in a crash due to a simple oversight by the most experienced pilot in the U.S. Army at the time, this flight led to the aviation industry pioneering operational and maintenance checklists.
Designed to overcome human ineptitude, attitude, and ignorance, the aviation checklist, written in simple and exact language familiar to the profession, was instituted to ensure that each and every pilot, from that point on, followed a consistent, set procedure prior to takeoff and landing. As head of the World Health Organization’s “Safe Surgery Saves Lives” program, Dr. Gawande successfully adapted that checklist into a simple, innovative tool for the medical field—and subsequently credited its use for a dramatic reduction in hospital and surgical deaths, regardless of hospital conditions. There’s a significant takeaway from this story for those of us who have an interest in the health and well being of industrial equipment and processes.
Lubrication checklists that don’t challenge or insult maintainers or operators (but are designed correctly and written in a concise manner similar to those used in the aviation and medical fields) can overcome ignorance and ineptitude and promote low risk through a high degree of consistency.
Take, for example, the sample checklist in the table above. Written in objective language, it points to minor, required steps for making modifications to the lubrication-system components of a gearbox. It specifically references Hi-Lo-fill indicators on the lubricant-reservoir sight gauge that help personnel make simple, yet accurate, Go/No-Go decisions when checking the reservoir, and a number and color identification of the grease nipple and grease gun that’s used to visually identify the correct lubricant amount and type for each bearing.
Color, though, is just one aspect of identification called out on the checklist. It also references the exact grease point and reservoir number, the specific grease that is to be used, and the amount of the grease to be deployed in displacement and grease-gun shot action. To correctly perform the procedures in this sample checklist, a grease-gun consolidation program—wherein all current grease guns are surrendered and replaced with one grease-gun style—must be implemented. This allows the maintenance group to determine the exact displacement by volume and gun “shot” action for all grease deployed in the plant. Different greases are assigned specific grease-gun and grease-point colors.
This “lubrication by design” approach requires almost no capital outlay. With some minor organizational effort up front, it can be rolled out systematically, machine by machine. In these times of diminishing technical skills and experience across industry, the alternative really isn’t much of an option. MT
Ken Bannister is managing partner and principal consultant for EngTech Industries Inc., (Innerkip, Ontario), an asset management-consulting firm specializing in the implementation of certifiable ISO 55001 lubrication-management programs and asset management systems. For further details, phone 519-469-9173, or email firstname.lastname@example.org.
Quick Tips for Successful Checklists
As I wrote in a March 2013 “Don’t Procrastinate, Innovate” column for Maintenance Technology, Dr. Atul Gawande’s 2009 book The Checklist Manifesto–How to Get Things Right, was, and still is, an intriguing read. It offers some invaluable insight for those in the reliability and maintenance field.
In his book, Gawande details how he pioneered the “Safe Surgical Checklist,” based on a model that the aviation industry adopted following the infamous World War II Boeing 299 crash. That checklist has certainly stood the test of time.
According to Daniel Boorman of Boeing (Seattle)—the person charged with developing aviation checklist manuals for all of the company’s planes for 20+ years—the secret of a good one is how it’s written, starting with using simple and precise language familiar to users in the profession. Among Boorman’s other tips:
— A checklist doesn’t have to be too comprehensive to be effective (usually between five and nine items).
— Well-designed checklists fit the flow of the specific work, encourage users to read each point out loud, and help them detect potential failures before they occur.
— A successful checklist ideally fits on one page, is free of unnecessary color and clutter, and uses upper and lower case in a sans-serif font such as Helvetica.