Archive | Lubrication

123

8:39 pm
April 12, 2017
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Specify the Right Lube-Delivery Line

Fig. 1. Cost should not be a factor in your lubrication-delivery-line choices. While the steel-tubing in this progressive-divider-lubrication system block took more time to install than plastic lines, the additional, but small, up-front cost will pay long-term dividends, especially if leaks or blockages occur.

Fig. 1. Cost should not be a factor in your lubrication-delivery-line choices. While the steel-tubing in this progressive-divider-lubrication system block took more time to install than plastic lines, the additional, but small, up-front cost will pay long-term dividends, especially if leaks or blockages occur.

The wrong lubrication-delivery line can compromise the reliability of your production equipment.

By Ken Bannister, MEch Eng (UK), CMRP, MLE, Contributing Editor

During lubrication-training workshops, I ask participants to name the components that make up a centralized lubrication system. Most will answer in the context of an automated-delivery system by citing the pump, reservoir, metering devices, and pump controller. Rarely do they actually include the lube-delivery lines in their answers.

Lubrication-delivery lines are important and integral components within centralized lubrication systems—be they state-of-the-art automated designs or simple, manual arrangements. Specifying the wrong type can put machinery reliability at risk.

The function of a lubrication-delivery line is straightforward: It must connect a bearing point to a lubricant source (indirectly from a meter or gang block, or directly from the pump) and allow the lubricant to be contained within the line to flow without constriction. As lube-delivery systems are hydraulic in nature, the line must also be capable of withstanding pressures ranging from hundreds to, in some cases, many thousand of pounds-per-square-inch (psi) of pressure.

Listen to the latest in a series of monthly lubrication-related podcasts with Ken Bannister. This edition of the podcast focuses on lubrication-delivery line matters.

Line size and material

Correct choice of size and material is essential if a lubricant-delivery line is to provide reliable service. For the most part, the line plays a passive role within a centralized system and is typically fixed to the side of a machine (the exception being where a lubricated part moves independently of a piece of fixed machinery, in which case, the line is used to provide the flexible connection.) Before a delivery line can be specified, however, a number of basic questions regarding the overall lube-system design must be answered, including:

Fig. 2. The bundled plastic tubing in this progressive-divider system are difficult to individually trace from pump to the lube block. These types of lubrication-delivery lines are also difficult to physically attach to a machine’s frame and, consequently, more vulnerable to damage.

Fig. 2.
The bundled plastic tubing in this progressive-divider system are difficult to individually trace from pump to the lube block. These types of lubrication-delivery lines are also difficult to physically attach to a machine’s frame and, consequently, more vulnerable to damage.

Is this system automated or manual? The answer is crucial in assessing line material, diameter, and wall thickness, which relate specifically to the line’s material-burst pressure rating.

• Manual systems designed to “gang” grease nipples in a central block can be lubricated by grease guns capable of developing as much as 15,000 psi.

• Manual hand pumps and automated systems operate at much lower pressures (between 100 and 2,000 psi).

What type of automated/engineered delivery system is specified? Some system designs require a single line size throughout, whereas others require a main and secondary line of different diameters and flow rates. For example:

• Single-line-resistance and pump-to-point systems are low-pressure systems designed to deliver the total amount of lubricant in one pump cycle. In such systems, i.e., total-loss, single-size-diameter delivery lines are sufficient.

• Single-line positive-displacement-injector, dual-line-injector, and progressive-divider systems require multiple cycles of the pump connected to a larger diameter main line used to rapidly fill the injectors/main distribution blocks, and smaller-diameter secondary lines that connect the metering outlets to the lubrication points,

• Re-circulating-oil systems usually require single-size-diameter delivery lines and a larger-diameter, return-line system.   

How many lubrication points are included in the system and where are they located on the machine? This question is required to map out a central pump location and injector or delivery block locations so the line distances can be measured for material take-off amounts, and in the case of long line lengths, to calculate pressure drop so the correct line diameter(s) can be calculated.

What lubricant type and grade/viscosity are you planning to use? The fact that grease requires higher pressure than oil to move through blocks and lines will affect the choice of line material type and diameter.

Fig. 3. If single-chamfered compression fittings designed for nylon lines are mistakenly used on steel lubrication-delivery lines that require double-chamfered fittings, seals can be compromised, causing leaks at the fittings. (Courtesy Bijur Delimon International, Morrisville, NC, bijurdelimon.com.)

Fig. 3. If single-chamfered compression fittings designed for nylon lines are mistakenly used on steel lubrication-delivery lines that require double-chamfered fittings, seals can be compromised, causing leaks at the fittings. (Courtesy Bijur Delimon International, Morrisville, NC, bijurdelimon.com.)

In what type of working environment will the system be used? Ambient and working temperatures can affect line integrity. Furthermore, if unprotected, copper, brass, and plastic lines can be easily damaged in high traffic areas—especially where lift trucks are used regularly.

What is your budget? Cost should not be a factor in line choice. Figures 1 and 2 show progressive-divider blocks, one piped in correctly rated plastic tubing and the other in steel. While steel tubing (Fig. 1) takes considerably longer to install, the additional, but small, up-front cost can pay long-term dividends, especially when a problem, such as a leak or a blocked line, occurs. The plastic tubing (Fig. 2) is bundled together. making it difficult to individually trace a line from the pump to the lube block. In addition, these lines are difficult to physically attach to the machine frame and, consequently, more vulnerable to damage.

Although the steel lines used in Fig. 1 are dirty, they all have line-ID (identification) tags that make them easy to trace and troubleshoot. The steel-line system also looks more engineered and permanent in comparison with the bundled-plastic-line example.

Once you’ve gone through these six questions, present the answers to your lube-system designer or manufacturer/supplier. These resources can help you determine the best line material for a specific application.

Main problem causes

Problems in lubrication-delivery lines manifest as leaks or blockages. A leaking line will starve lubricant from one or many bearing points and seriously affect the associated production equipment’s reliability. Leaks are invariably found at connection points and line-bend areas. Keep the following in mind:

• Copper lines are very soft and can easily work-harden at bend points if significant machine vibration occurs.

• Nylon lines can be easily over-tightened or not cut square at the connection points. This can cause a leak at the compression fitting.

• If a single-chamfered compression fitting designed for nylon lines is mistakenly used on a steel line, which require a double-chamfered compression fittings (see Fig. 3), they can be compromised, causing a leak at the fitting.

• To reduce cost, nylon lines can be used as a substitute for flexible-hose lines in moving-bearing-point applications found on, among other things, machine slides and rams. Plastic lines, in most cases, are not rated for cyclic repetitive-movement duty.

Blockages in lubrication lines usually occur when they’re pinch-damaged from being hit by a foreign object that crimps or flattens the line shut. This situation causes a line backpressure that can blow the fitting or eventually stall an entire progressive-divider system, starving many bearings in the process. Steel lines offer the best defense against pinched lines.

Best practices

To ensure no bearing is starved after a lubrication-system implementation or line replacement, always pre-fill the lubricant line with the correct grease lubricant before final fastening to the bearing. Or, in the case of oil, operate the lube system and open all bearing points to ensure oil is flowing at each point before final tightening.

Finally, never forget that lubrication-delivery lines are a matter of choice. Reliable lube systems, in turn, depend on making the correct choice. MT

Contributing editor Ken Bannister is co-author, with Heinz Bloch, of the book Practical Lubrication for Industrial Facilities, 3rd Edition (The Fairmont Press, Lilburn, GA). As managing partner and principal consultant for Engtech Industries Inc. (Innerkip, Ontario), he specializes in the implementation of lubrication-effectiveness reviews to ISO 55001 standards, asset-management systems, and training. Contact him at kbannister@engtechindustries.com, or telephone 519-469-9173.

976

3:23 pm
January 4, 2017
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Understand Motor and Gearbox Lubrication

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Over-lubricated bearings will produce excess heat through internal fluid friction that can easily be detected with an infrared camera. Photo: Fluke Corp.

Among other factors, motor and gearbox lubrication programs require understanding and a controlled lubrication approach.

By Ken Bannister, MEch Eng (UK)CMRP, MLE, Contributing Editor

When a driven component is required to operate at a speed different than that of the attached motor (driver), a designer can choose from two basic power-takeoff speed-reduction/increaser methods. The first uses pulleys or sprockets of different diameters mounted to the motor and driven shaft, with power transmitted by a connective belt or chain. The second design connects the motor to the driven component through a gearbox, with the motor connected to the gearbox input shaft and the driven device connected to its output shaft.

When viewed in a maintenance-management-system database for lubrication purposes, belt/chain-drive motors and motor/gearbox units are rarely handled with separate PM work orders. Rather, the lubrication requirements are integrated as line items on a much broader machine PM work order. This is fine for sub-fractional and smaller horsepower motors. Larger, more expensive (and re-buildable), motors—usually 20 hp and more (there is no set rule to this)—require treatment as a separate entity from the parent machine, with their own asset numbers and PM/lubrication regimes, so as to compile work-history files. Furthermore, in the case of  motor/gearbox combinations there are two specific entities, one electro-mechanical (motor), the other purely mechanical (gearbox), that are best treated individually when assessing and managing lubrication needs.

Assuring motor and gearbox reliability is the result of good alignment practices and, more importantly, effective lubrication practices.

Bannister on Lubrication

Accompanying this article is the first of a new series of monthly lubrication podcasts with Ken Bannister. This month, he provides additional information about factors involved in lubricating motors and gearboxes.

Motor lubrication

Motors are electro-mechanical devices that turn electrical energy into mechanical energy. Motor magnets and windings are wound on and around a central shaft. This shaft is simply supported by two or more rolling-element bearings at each end of the motor frame and housing. These bearings are the only lubrication points on a motor, and are virtually always grease lubricated. With rare exception, fractional- and small-horsepower motors use sealed bearings and make no provision for external bearing lubrication. If the motor is balanced, aligned, and not overloaded, it should deliver a long life with no additional lubrication. This is not usually the case with larger motors, which are often subjected to heavier and often more variable loads, requiring larger bearings.

Depending on the motor design and manufacturer, external grease fittings usually are installed on motors rated at 5 hp and become much more prevalent on 20-hp units. When motors become more powerful and heavier, they place more load on the bearing points, therefore requiring grease replenishment on a more-frequent basis.

If a motor is to operate at peak efficiency, its bearing cavities (the available space between the balls, raceways, cage, and seals) need only be filled to 30% to 50% capacity, at any time. Because the bearings are hidden behind end plates, they are lubricated “blind” and are often subject to overfilling—especially with manual greasing. When this happens, the grease has nowhere to go except through the bearing cavity into the winding! Grease-filled windings lead to premature failure and a rapid decrease in motor energy efficiency, evident by the rise in motor’s amperage draw.

To alleviate this condition, larger motors are designed with a drain-plug or screw in the end cases that, once opened, will allow excess grease to flow through the bearing and out of the motor end case. If this is kept closed during the greasing process, excess grease will channel directly into the motor windings. If your motor has a grease fitting but no drain plug, use extreme caution not to over-lubricate, as the excess will make its way into the winding.

Over-lubricated bearings will produce excess heat through internal fluid friction that can easily be detected with an infrared camera. This can also be achieved by adding contaminated grease with a dirty grease nozzle or through cross contamination with a non-compatible grease.

Grease-gun inconsistency can be ironed out through use of a single-point auto lube (SPL) setup to deliver a small amount of lube on a continuous basis for as long as a year, depending on the size of bearing and lube reservoir.

SPL manufacturers have setup guidelines based on bearing size and altitude (atmospheric pressure is relational to constant-pressure grease flow) for initial setup, which can then be fine-tuned by monitoring amperage draw and/or bearing temperature. These signatures will be unique to each motor and will differ based on size and load.

Gearbox lubrication

Gearboxes are self-contained mechanical devices that allow power to be transmitted from an input shaft to an output shaft at different speeds through the meshing of different-sized gear sets held on each shaft. The gears and shafts are supported on bearings contained within a sealed “box” that also serves as a reservoir for the lubricating oil. Gearbox dimensions can range from palm-sized to room-sized. With few exceptions, all are oil lubricated.

Depending on the style and size, gearboxes employ a number of methods to move the lubricant over the gears and bearings, the most popular being:

• Splash lubrication. This is a common gearbox-lubrication method in which the reservoir is filled part way with lubricating oil to ensure partial coverage of all the lower mating gears. At speed, these gears use surface tension on their teeth to “pick up” lubricant and transfer to other gears and bearings through meshing and by “flinging and splashing” the lubricant in all directions within the sealed reservoir.

• Pressure lubrication. This method is frequently found on mid- to large-sized gearbox assemblies that use a gear-driven pump, typically located inside the gearbox, to work in conjunction with the “splash” method. Pressure-lubrication systems draw lubricant from the reservoir through a pickup-filter screen and pump oil at pressure through an internal piping system to bearings and gears that would be difficult to service with splash lubrication.

• Mist, or atomized, lubrication. This approach, reserved for the largest of gearboxes, uses a vane-style pump that picks up lubricant from the reservoir and “slings” it at a plate, causing it to atomize into a micro-drop mist. The mist saturates all of the mechanical components within the sealed gearbox.

In all three lubrication methods, choosing the correct oil viscosity and additive package is most important. Typical to all gearboxes is the need to ensure:

No cross-contamination of lubricants occurs during oil top-ups or change-outs. Label your gearbox with the correct oil specification.

No dirt or water contamination is allowed into the gearbox.

The drain, fill, and breather caps are always tightly in place.

The gearbox is regularly wiped clean of dirt and debris that will act as a thermal blanket and unnecessarily heat up the oil.

The gearbox is not over-filled creating churning (foaming) of the oil that can rapidly deplete the anti-foam additive, causing the oil to oxidize. This requires attaching low- and high-level markers to the gearbox sight gage.

If you have all of the above practices in check, make enquiries regarding the use of synthetic gear oils. These not only last longer but can cut your energy consumption as much as 4%. MT

Ken Bannister is co-author, with Heinz Bloch, of the recently released book Practical Lubrication for Industrial Facilities, 3rd Edition (The Fairmont Press, Lilburn, GA). As managing partner and principal consultant for EngTech Industries Inc. (Innerkip, Ontario), he specializes in the implementation of lubrication-effectiveness reviews to ISO 55001 standards, asset-management systems, and training. Contact him directly at kbannister@engtechindustries.com, or telephone 519-469-9173.


learnmore2“A Real-World Approach to Electric Motor Lubrication”

“The Inner Life of Bearings, Parts 1 and 2”

359

3:30 pm
November 15, 2016
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Control and Avoid Lubricant Contamination

Conveyor belt detail on mining site

Clean lubricants increase the life and performance of bearings and ensure the success of your operations.

By Ken Bannister, MEch Eng (UK), CMRP, MLE, Contributing Editor

I am astounded by the number of companies that continue to believe bearing failure and its associated replacement and downtime costs are an acceptable part of doing business. In my experience, this point of view is most apparent at sites with severe and semi-severe operating conditions, wherein water, heat, and fine particulate matter (dust, dirt, and manufacturing debris) are present.

If a machine has any form of replaceable/washable filter, screen, or breather as part of its fluid-management systems—lubrication, hydraulic, and pneumatic-air systems—we can assume the OEM (original-equipment manufacturer) machine designer/engineer expected the equipment and its operators/maintainers to contend with and manage fluid- and air-borne contaminants. These built-in sacrificial filtration elements are specifically designed to provide an inexpensive method of managing and controlling potential contamination issues—externally and internally—to protect delicate, close-tolerance, machine-bearing surfaces at work under a range of operating conditions.

In the majority of operating conditions, effective levels of contamination control and avoidance are achievable with minimum effort when the requirements and basic relationships of and between a machine, its operator(s), and maintainer(s) are understood.

The fact that a piece of equipment begins to run a process or make a product indicates the OEM has done its part: supplied a machine that’s adaptable enough to work in an array of different operating environments or, if the end user is fortunate, one designed and built specifically for a unique operating environment. This means the machinery is fitted with a number of built-in contamination-control/filtration devices that are ultimately designed to fail in their own right. (They also require monitoring for condition and cleaning and/or replacement when their filter media is close to being exhausted.) These devices offer secondary protection through their ability to trap and control the ingress of contaminants into lubricating oil(s), grease(s), and air-flow systems.

Contamination control

When two precision-bearing surfaces interact, they rely implicitly on a lubrication film devoid of particle or water presence to separate—and protect—themselves from each other. The filter is designed to trap and extract any particles or moisture before these contaminants can enter the lubricated zone(s) and cause surface damage.

Almost exclusively in contamination control, filters incorporate a passive surface-attractant medium, designed to work in the direct-flow path of the lubricant and capture any dirt particles (contaminants) held in colloidal suspension as the lubricant, or lubricated air, flows through or across it. Depending on the working conditions, particle size, and fluid-flow rate, the porous filter media can be constructed of a variety of materials, including simple wire-mesh gauze, wire wool, pleated paper, cellulose, porous metal, fiberglass, diatomaceous earth, or felt. Due to higher fluid viscosity and line-delivery pressures, grease systems use heavy-gauge coiled wedge-wire or wire-mesh filters to attract large solid contaminants that may be introduced from a dirty grease-gun nozzle.

Enclosed, sealed gearboxes and reservoirs require breather devices to equalize pressure and control solid and moisture contamination. Old-style breathers constructed of wire wool can only prevent large solid contamination (40+ microns in size), and are now regularly replaced with newer-style breathers that employ desiccant-like silica gel hydrophilic media.

This media type allows the reservoir to breathe and prevent airborne particulates (3+ microns) from entering the reservoir. It also wicks and captures moisture from inside the reservoir, while preventing outside moisture from entering the reservoir or gearbox chamber.

Heavy water contamination usually enters a system as a result of maintenance or production personnel using oil that has been incorrectly stored in the outside elements, or through production-process-water spillage or high-pressure machine-cleaning (prevalent in food-manufacturing machinery).

Contamination avoidance

Ironically, while contamination avoidance is the primary strategy for reducing and eliminating premature bearing failure, it is absent/avoided in many lubrication programs. A good contamination-avoidance program requires little-to-no capital outlay, fits perfectly into any preventive-/predictive-maintenance (PM/PdM) program, involves cooperation of operators and maintenance personnel, and will drastically reduce the reliance and maintenance requirement of what essentially become secondary contamination-control systems.

In simple terms, contamination-avoidance means taking actions to ensure that contaminants don’t come into contact with a machine and its bearing-protection systems. Success relies, largely, on a good relationship between operations and maintenance personnel and a healthy respect for the machine and components in question. The following points outline the foundational requirements of any contamination-avoidance program:

Good housekeeping. Ensuring that dirt does not accumulate on equipment surfaces is preventive maintenance 101 and the responsibility of operator and maintainer. Implementing a simple 5S program will facilitate this element. This applies to the machinery and the lubricant-storage area and transfer equipment.

Lubrication training. Understanding the effect and consequence of failing to arrest contamination is mandatory. Use processes and procedures that ensure consistent effort.

Lubricant storage and transfer engineering. Using dedicated, color-coded, and closeable storage and transfer equipment protects lubricants from the elements and cross-contamination exposure. Make sure all grease guns and nipples are cleaned with lint-free rags before and after use.

Condition-based oil changes. Performing oil/filter changes too frequently risks exposure to contaminants. Performing them too infrequently risks exhausting filtration media and, in turn, lubricating-fluids degradation. Condition-checking allows operators and maintainers to become more familiar (or in tune) with a machine.

Lubricant cleanliness. Testing new lubricants and bulk fluids to verify their cleanliness and additive-package formulations before they’re put into use is a must. This is the only way to ensure that they’ve been delivered in a clean state and meet referenced specifications. In addition to the above behavioral changes, the following equipment and workspace changes can be put in place if the production process and workplace environment warrants:

Room-ventilation system. Positive or negative room pressurization or exhaust-air ventilation can be used to reduce or eliminate airborne contaminants.

Machine design. If the production process involves water or sand, mechanical deflector shields can be used to protect, divert, and channel contaminants away from bearing and lubricant-reservoir areas. Fill-cap and drain-port plugs can be replaced with positive-lock fill/drain connections that hook to closed-system transfer carts. Conventional breathers can be replaced with a closed-loop expansion tank on larger reservoir systems.

Taking small contamination-avoidance steps will significantly reduce your site’s lubricant-contamination-control requirements. The savings from these efforts can then help fund your world-class lubrication-management program. MT

Ken Bannister is co-author, with Heinz Bloch, of the soon-to-be-released Practical Lubrication for Industrial Facilities, 3rd Edition (The Fairmont Press, Lilburn, GA). As managing partner and principal consultant for EngTech Industries (Innerkip, Ontario), he specializes in the implementation of lubrication-effectiveness reviews to ISO 55001 standards, asset-management systems, and training. Contact him directly at kbannister@engtechindustries.com, or telephone 519-469-9173.


learnmore2“Store and Handle Lubricants Properly”

“How Clean is the New Oil in Your Equipment?,”

“The Inner Life of Bearings, Part I: How Lubrication Really Works”

163

2:56 pm
September 13, 2016
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Win the War with ‘Lubrication by Design’

Use aviation-style checklists to eliminate ambiguity and errors in your lubrication-maintenance procedures.

By Ken Bannister, MEch Eng (UK) CMRP, MLE, Contributing Editor

The Sample Gearbox-Lubrication Checklist in the table below points to Hi-Lo fill indicators that help personnel make simple, yet correct, Go/No-Go decisions when checking lubricant reservoirs. Image courtesy of EngTech Industries.

The Sample Gearbox-Lubrication Checklist in the table below points to Hi-Lo fill indicators that help personnel make simple, yet correct, Go/No-Go decisions when checking lubricant reservoirs. Image courtesy of EngTech Industries.

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

The checklist below points to number- and color-identification of grease nipples and grease guns as a way to quickly and accurately determine the correct lubricant amount and type for each bearing in the referenced gearbox. The solution shown here is from OilSafe (oilsafe.com), Rockwall, TX.

The checklist below points to number- and color-identification of grease nipples and grease guns as a way to quickly and accurately determine the correct lubricant amount and type for each bearing in the referenced gearbox. The solution shown here is from OilSafe, Rockwall, TX.

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.

screen-shot-2016-09-13-at-9-47-12-am

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.

Bottom line

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 kbannister@engtechindustries.com.

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.


learnmore2“Power from Making Lists and Checking Them Twice”

“Safe Surgical Checklist” on the World Health Organization website

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