Archive | Delivery Systems

853

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.


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

230

8:29 pm
December 20, 2016
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Tune Your Lube-Delivery System

This mechanically actuated grease pump uses a pitman-arm control connected to a large-diameter rotating-machine shaft. The shaft attachment point is offset from the center to produce a reciprocating arm motion that produces a rocking motion at the pump shaft. This emulates the back-and-forth motion of the manual lever arm. Photo: EngTech Industries Inc.

This mechanically actuated grease pump uses a pitman-arm control connected to a large-diameter rotating-machine shaft. The shaft attachment point is offset from the center to produce a reciprocating arm motion that produces a rocking motion at the pump shaft. This emulates the back-and-forth motion of the manual lever arm. Photo: EngTech Industries Inc.

Optimizing a lubricant-delivery system is not difficult and the benefits are significant.

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

When a piece of rotating machinery is purchased, it almost always is delivered with a designed lubrication system or approach in place. The type of equipment can be as complex as a high-end, integrated, computer-controlled, automatic lubricant-delivery system that supplies each bearing point with a measured amount of lubricant based on time, cycle, or condition.

Or, if a site’s budget was tight during the initial specification and procurement process, its new machinery could arrive with a more modest form of lubrication technology involving inexpensive grease nipples and/or oiling points at each bearing point and the simplest of instructions in the operations and maintenance manual to “lubricate as necessary with a specified lubricant.”

Those examples represent the extremes in lubrication design and approach. Fortunately, from one extreme to the other and in between, maintenance-department personnel have the ability to tune lubrication-system setups to improve/optimize their particular lube-program deliverables. It’s not as daunting a task as it might seem.

Lubricant-delivery systems are typically designed with one or more areas of adjustability to allow tuning. Take advantage of this capability. Depending on the design mechanics of the system, tuning adjustability can be found in three major places: the metering devices, the pump, and the pump-control system.

Metering devices

Adjustable metering devices, such as those found in single-line, positive-displacement, injector (PDI) systems (oil or grease); dual-line injector systems (oil or grease); or pump-to-point box-cam systems (oil only) allow plant personnel to change the amount of lubricant charge that’s delivered to specified lubrication points. These types of systems are less expensive to design, as they require little or no initial design engineering and put the injector-calibration setup responsibility squarely on the user. The downside to this scenario is that it can easily lead to over- or under-lubrication if the user isn’t familiar with the equipment or doesn’t understand how to calculate a bearing’s lubricant requirements. Maintainers and machine operators can also tinker with settings at will if they feel a bearing requires more or less lubricant—a situation that doesn’t merely change the dynamic from adjustability to “tamperability.” It, too, can lead to over- or under-lubrication and, ultimately, premature bearing failure.

Tuning such systems necessitates calculating the hourly bearing requirement and determining the minimum-to-maximum lubricant output shot per cycle for each injector size/type. The accumulated total amount of lubricant is what must be pumped through the delivery system every hour, and the system must be set up accordingly. From this point on, with all injectors calibrated, any further adjustment is to be carried out at the pump.

Protecting these systems from tampering calls for controlled access. This can be accomplished in numerous ways, the simplest of which is “ganging” multiple injectors together, building a key-access lock-box around them, and allowing access only to designated lubrication or reliability personnel.

NOTE: Popular single-line-resistance and progressive-divider metering devices are non-adjustable. They depend on upfront engineering by the system supplier (incorporated in the cost of the system), before delivery to the machine builder or end user. Their setup adjustability is through pump-output calibration. 

Lubrication pumps, controllers

Lubrication pumps, which come in many configurations and sizes, can be powered manually, electrically, or pneumatically. The delivery rate for all of these can be adjusted on the pump itself or through a pump controller.

Manual pumps are mechanically actuated with a lever arm connected to a positive-displacement piston. The output delivery can be adjusted by restricting the length of the piston stroke with an adjustment at the lever cam. Lubricant is manually drawn into a single-acting piston chamber by moving the lever arm in a back-and-forth arc motion. The lubricant is then moved out of the pump through an internal check valve to the distribution lines and on to the metering devices. The pump is returned through opposite action on the lever or by a return spring.

If reciprocating or rotary machine motion is available, the lever arm of the manual pump can be replaced with a power-takeoff pitman-arm linkage attached to the motion device. The photo on the previous page shows a series-progressive distribution system with a mechanical pump attached to a pitman arm that’s connected to a large-diameter rotating-machine shaft. The shaft attachment point is offset from the center to produce a reciprocating (up and down) arm motion that produces a rocking motion at the pump shaft. This emulates the back-and-forth motion of the manual lever arm.

By changing the length relationship of the pitman-arm attachment point and arm, the degree of arc will change and speed up or slow down the number of pump strokes per hour. As evidenced by the surplus grease around the bearing in the photo, the pump setting is incorrect and needs to be recalibrated to reduce the amount of lubricant delivery.

Pneumatically or electrically powered lube pumps are sized according to the system output requirement per hour. For effective lubrication, smaller amounts of lubricant, delivered on a frequent basis, e.g., every 10, 15, or 20 min., are preferable to a large amount that’s delivered hourly. This approach allows the designer to use a smaller, less expensive output pump and control and provide the ability to adjust total delivery through the number of actuations or lubrication cycles per hour. Setup is accomplished through programming (adjusting) the on/off timer that controls power to the pump.

Pump-lubrication cycles can be controlled in other ways, including through counters that calculate the number of machine or production operations, or by a condition signal, such as an amperage-draw meter that indicates an increase in energy draw from the machine-system motor (due to a rise in mechanical friction that’s most often caused by lack of lubrication). This popular control mechanism is used in automotive-assembly plants to measure the amperage of conveyor-drive and take-up motors that activate and deactivate conveyor chain and pin lubricators.

In simple, modestly priced, manual-grease systems, a grease-gun acts as the pump and metering device, while control is regulated by the grease-gun user and the scheduled preventive-maintenance (PM) instruction. Optimization and setup involves a two-step process in which the grease-gun’s displacement must be determined to first ascertain the number of shots required to meet the bearings’ calculated needs and, second, the frequency of application that must be controlled by the PM schedule. The number of grease-gun shots or the PM schedule is used to fine tune any increase or decrease in the lubrication amount or frequency.

Keep in mind

Automated lubricant-delivery systems are much more accurate, consistent, and easier to set up and control than manual systems. As a result, bearings run cooler (due to less friction), require less energy, and have as much as three times the service life of their manually lubricated counterparts. In short, return on investment from the relatively small purchase and implementation cost of an automated system is quickly realized. 

Regardless of its design, a lubrication-delivery system should be evaluated on a bi-annual basis to assess its effectiveness. Those evaluations should include reviews of bearing-failure incidents, grease usage, changes in bearing running temperatures and energy draw, as well as checks for physical signs of over-lubrication and system neglect. As with the initial setup of these systems, a little adjustment later on—make that a little fact-based, correct adjustment—can pay enormous dividends. MT

Ken Bannister is co-author, with Heinz Bloch, of  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 at kbannister@engtechindustries.com, or telephone 519-469-9173.


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“Several Hands Responsible for This Oil Debacle”

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60

9:00 am
July 15, 2016
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Battery-Driven Grease Gun

1607mtprod20pTLGB 20 battery-driven grease gun has an integrated grease meter to dispense the proper amount of lubricant for an application. A rechargeable 20-V lithium battery delivers extended service life. A built-in light illuminates the work area. The gun dispenses as many as 15 grease cartridges/battery charge and has two flow rates adjustable for specific application. Pressures to 10,000 psi can be achieved.

SKF USA Inc.
Lansdale, PA
skfusa.com

178

1:48 am
March 9, 2016
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Simalube IMPULSE Pressure Booster Overcomes Long-Lubrication-Line Challenges and More

Screen Shot 2016-03-08 at 7.30.22 PMsimatec Inc. (Charlotte, NC) refers to its recently launched simalube IMPULSE pressure booster (up to 145 psi) as “the perfect complement” to its 60-, 125-, and 250-ml simalube lubricators. An addition to the company’s portfolio of smart technologies, simalube IMPULSE is well suited for high-counterpressure applications and systems with long lubrication lines (up to 4 meters, or approximately 13 feet, in length.). The unit’s compact size allows installation in the smallest of spaces, in all positions, even underwater. As an IP68 protection class device, it’s dustproof, waterproof, and appropriate for use in a wide range of industries.

Screen Shot 2016-03-08 at 6.48.16 PMHow It Works
According to the manufacturer, users simply affix the simalube IMPULSE to the selected lubrication point, screw on the required simalube lubricator and activate the unit for the desired dispensing time. The device starts operating as soon as a battery pack is inserted and the lubricator is attached. Continuous lubrication impulses of 0.5 ml supply the lubrication point with oil or grease up to NLGI 2 at a pressure of up to 10 bar. This action is gentle on the lubricant, as only the dosing volume is placed under pressure.

This simalube IMPULSE also continually signals its operating state. When the unit is properly installed, an LED indicator flashes green at regular intervals. Red flashes indicate overpressure, inactive, and empty conditions. Although dispensing intervals set by the lubricator may change, this intelligent pressure-boosting device will automatically adjust.

Maintainability and Service Life
During lubricator change-outs, the simalube IMPULSE stays firmly affixed to the lubrication point. The connection point remains sealed throughout the process, and no lubricant back-flow occurs. Equipped with a fresh battery pack after each lubricator change-out, the pressure-booster can be used multiple times (for 10 simalube 125 ml dispensing cycles or for up to three years).

For more information, CLICK HERE.

 

 

417

5:28 pm
January 12, 2016
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Lubrication Strategies: Several Hands Responsible For This Oil Debacle

The actions of personnel can either lead to great success in lubrication programs or, as this case study shows, to costly calamity.

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

Lubrication team members must understand how their actions can have negative upstream and/or downstream impact should they neglect to effectively and efficiently fulfill their roles.

Lubrication team members must understand how their actions can have negative upstream and/or downstream impact should they neglect to effectively and efficiently fulfill their roles.

Winston Churchill wrote, “Responsibility is the price of greatness.” These words have special meaning for those of us in the lubrication field.

In organizations that seek to become great, all personnel must understand the negative upstream and/or downstream impact that their individual actions could have should they neglect to effectively and efficiently fulfill their roles. This is especially true of lubrication team members, who, through daily interaction with machinery and moving parts, are directly responsible for the successful lubrication of equipment in their charge—as well as for any consequences resulting from their activities. Their failures will manifest directly in the loss of equipment availability, reliability, and life-cycle longevity, and indirectly through production yield and quality losses.

A case in point

My look into the oil and grease purchasing patterns of a major North American automotive-assembly manufacturer during a lubrication-operations effectiveness review (LOER) was a real eye opener. I was astounded by the many tens of thousands of dollars per month the corporation was spending on just one type of chain-lubricant oil.

This automatic-chain-lubricator oil was a name brand, premium-quality, molybdenum disulphide, high-temperature formulation. Designed specifically to lubricate power- and free-conveyor chain pins and bearings passing through the types of high-temperature paint-bake ovens found in automobile assembly lines, it was an ideal match for the application. So, given those facts, why was the facility using so much of the product for just four conveyor-lubricator systems? Moreover, why had the lubrication staff or the lubricant supplier neither noticed nor brought to management’s attention the systems’ dramatic (more than 10-fold) increase in lubricant consumption over the past two years?

Further investigation revealed that the chain-oil consumption increase had coincided with the hiring of a new lubrication technician. The PM (preventive maintenance) job plan and frequency for checking and filling the automated lubricator reservoirs, though, had remained unchanged—from the time the devices were installed and commissioned more than three years prior. This discovery prompted a physical investigation of the four lubricators themselves. The findings were more than surprising!

The four lubricators were a popular, highly reliable brand. Low-tech in design, they used a pneumatic pump-to-point-style pump connected to dynamic injectors that would “volley” or “shoot” a small fixed amount of oil into either the unshielded trolley rolling-element bearings or the chain-link pins that connected the trolleys.

All of the devices were in excellent condition—and still located where they had been originally installed—complete with reservoirs full of oil. Curiously, though, all had been shut off electrically at the breaker and their pneumatic air supplies had been shut off at the feed-line valves. As a result, all of these units were totally useless.

Investigators subsequently learned that the four original lubricators had been “replaced” further down the conveyor line by a makeshift gravity-lubrication system that featured 1-gal. paint cans clamped to the conveyor I-beam as oil reservoirs. Installed in the bottom of each can were two small cock valves fitted with copper lines dropping down to two commercial, adjustable oil-drip brushes that were very wet with lubricant—just like the over-lubricated conveyor chain and roller bearings they served.

Questioned about this state of affairs, the plant’s production and quality supervisors told a story of numerous paint-quality problems that, they believed, had been caused by lubricant over-spray. After complaining about the matter to the new lubricant technician, they said, the situation eventually seemed to improve, i.e., fewer quality incidents occurred.

When interviewed, the lubrication technician reported that upon assuming his new role he had received no formal training or direction other than to follow the instructions on the work orders and use common sense. Shortly after starting the job, because of the workload, he decided to ignore the automated lubricator PM work order and, instead, rely on the lubricator-reservoirs’ low-level lights as condition indicators for adding oil. After the first three months, all low-level indicators had activated, at which time the technician had correctly filled the reservoirs with the correct oil (or so he thought).

During later lubricant checks, however, the reservoirs appeared full, and didn’t seem to be dispensing oil at all. Consequently, after multiple unsuccessful attempts to alert his supervisor to the situation, the technician took it upon himself to exercise his personal version of common sense and engineer a new system. Thus was born the gravity system of paint cans and brushes—for which, incidentally, almost a year had been spent working out the settings so that oil wouldn’t drip off the conveyor on to the painted vehicles. (To his credit, the technician did show the new system to the lubricant supplier’s representative. Accordingly, after approving the design, the rep also began enjoying increased orders and commissions for his product.)

In the end, simple diagnostics performed on the automated chain-oil lubricators found the units to be in perfect working order. The reason they had failed to dispense lubricant? At some point, their oil levels had been allowed to drop so low that the injectors and pumps lost their prime. The devices simply needed to be re-primed.

Lessons learned

As this case study shows, a few simple lapses in responsible behavior resulted in serious quality issues requiring many hundreds of thousands of dollars in vehicle repaint costs, many tens of thousands of dollars in excess lubricant costs, and overall reduced conveyor life due to ineffective lubrication practices.

Many readers might vote to place blame wholly on the lubricant technician for this calamity. In this story, though, he should only take partial blame: A millwright by trade, with no formal lubrication training, he had been placed in his position based solely on seniority. To exacerbate the situation, there were no specific priming instructions regarding the automated lubricators, either in the work-order job plan or on or near the units themselves.

Still, while the technician tried unsuccessfully, on several occasions, to notify his supervisor of the lubricator problem, he also chose to ignore the initial PM in favor of a different lubrication approach without performing a risk analysis. His McGyver-style paint-can fix could definitely be construed as irresponsible for a tradesperson. He should, at the very least, have tried to find an operations manual or learn more about the specific lubricators he was dealing with before condemning them so quickly and creating a bigger downstream problem.

Much of the blame, however, really belongs to the site’s supervisory personnel:

  • the maintenance supervisor who irresponsibly did not adequately support his technician or notice the makeshift lubricators and/or the massive increases in his monthly lubricant spend
  • the production supervisor who irresponsibly bypassed the maintenance supervisor in favor of speaking directly to the lubrication technician.

Final blame goes to the irresponsible actions of the lubricant supplier. From an ethical standpoint, its representative certainly should have discussed the massive increase in chain-oil consumption with the plant’s maintenance supervisor and/or the purchasing department.

Responsibility is born out of knowing what to do and when to do it. In the case of the four referenced automated chain lubricators, problems could have been prevented with:

  • lubrication certification training
  • clear workflow processes
  • improved PM work-order job plans
  • standardized operating procedures
  • failure risk analysis on critical equipment
  • improved inter- and intra-departmental communications.

To be sure, the lubrication technician in this story was out of his depth. With a little effort, however, the costly scenario that he created could have been avoided.  MT

Lubrication expert Ken Bannister is principal consultant with EngTech Industries, Innerkip, Ontario. He is the author of Lubrication for Industry and the Lubrication Section of the 28th Edition of Machinery’s Handbook (both Industrial Press, South Norwalk, CT), contact him at kbannister@engtechindustries.com.

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870

6:37 pm
June 12, 2015
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Lubrication Checkup: Oil “Lumps” Blocking Injectors

1014lubecheckupBy Ken “Dr. Lube” Bannister

Symptom

We have experienced lubricant-injector failures in a number of our conveyor lubricators. We’ve used the same brand of high-temperature chain oil for the past five years without issue, except for the last drum. In that drum, we discovered coagulated “lumps” floating in the oil. The oil supplier is blaming our storage practices. Meanwhile, we’re having great difficulty getting the lubricators to work, despite changing the oil for fresh product. Any suggestions?

Diagnosis

Regarding lubricant condition, oil has a shelf life determined by base-oil type, additive-package ingredients, and the finished product’s storage prior to use. Most lubricating-oil manufacturers claim an estimated shelf life of +/-5 years when their products are stored correctly indoors. Wide temperature swings, however, can result in wax and sediment creation (if the oil gets too cold), premature oxidation (if it gets too hot), and condensation-moisture contamination from hot/cold temperature cycling. Interestingly, high-temperature lubricants can be manufactured with volatile carrier agents that can flash off during storage (especially if open to air) and cause the remaining lube to “thicken” or coagulate.

Regarding your lubricators, injector-style conveyor designs require priming on the lubricator’s initial fill or when the lubricant level falls below the pick-up tube point. Badly contaminated or coagulated lubricants can make the injector difficult or impossible to prime.

Prescription

  • Always check with your supplier about the shelf life of your lubricant(s) and develop a purchase-quantity and stock-rotation strategy based on first in/first out principles and current usage patterns. To promote freshness, buy small amounts on a frequent basis and always use an indelible marker to note the receipt date on lubricant containers when they are delivered.
  • Never store new containers of lubricant outdoors without protection from the elements. If possible, strive to store all oils and greases in a dry, indoor location at a temperature range between 0 and 110 F.
  • Ensure that all lubricant-container bungs, lids, and breathers are always in place.
  • Use a suitable cleaning or flushing agent to remove old oil from your lubricators, pumps included.
  • Finally, remove and replace injectors with new ones of the same size, then prime the lubricator with fresh oil, according to the manufacturer’s instructions.
  • Proper storage will go a long way toward achieving specified lubricant performance. MT

Ken Bannister of Engtech Industries Inc., is a lubrication management specialist and author of Lubrication for Industry (Industrial Press), and the Lubrication section of the 28th Edition Machinery’s Handbook (Industrial Press). For in-house ICML lubrication-certification training, contact him at 519-469-9173 or kbannister@engtechindustries.com.

1709

7:37 pm
December 1, 2014
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Lubrication Checkup: Grease Delivery Lines

1014lubecheckupBy Dr. Lube, aka Ken Bannister

Symptom:

“Recent fork-lift damage to one of our machines affected several steel grease-delivery lines connected to one of the Trabon automatic-greasing system’s lube blocks. Can I rely on the lube pump to pre-fill the replacement lines?”

Diagnosis:

A typical Trabon centralized grease-lubrication system consists of a pump assembly connected to a number of progressive divider distribution blocks. Each block has one line in and numerous lines out, connected to either a secondary distribution block or direct to the lube points. Each discharge point on a block could be feeding a different size bearing requiring differing amounts of grease. Therefore, the system and blocks must be custom engineered and built prior to assembly on the machine, and all lines filled prior to use. When a charge of grease is pumped into the block, the pistons actuate progressively, one after another, as the lubricant moves through the porting in the block and the correct amount is delivered to each bearing point.

Prescription:

Remember that you are dealing with a hydraulic system. Its lines must be pre-filled prior to startup so that small, apportioned amounts of grease discharged at the block can simultaneously hydraulically push an equal amount of grease at the line end into the bearing. Using the lube pump to fill lines will take a very long time due to the apportioning aspect of the system. In the process, some bearings could fail as a result of lube starvation.

All block discharge points have the ability to be piped into the side of the block (the most common arrangement) or into the front. Both discharge exits are connected, and the unused one will be plugged. Simply undo this plug and screw in a regular grease nipple. Next, undo the corresponding end of the grease line at the bearing point, connect a grease gun and hand-fill the line.

Once grease appears at the bearing-point end, reconnect the line, take out the grease nipple and re-plug the block. Repeat for all delivery lines and you are good to go! MT

Ken Bannister of Engtech Industries, Inc., is a Lubrication Management Specialist and author of Lubrication for Industry (Industrial Press), and the Lubrication section of the 28th Edition Machinery’s Handbook (Industrial Press). For in-house ICML lubrication-certification training, contact him at 519-469-9173 or kbannister@engtechindustries.com.

1594

4:56 pm
September 23, 2014
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Lubrication Checkup: How to Correct SPL Failures

1014lubecheckupBy Dr. Lube, aka Ken Bannister

Symptom:

“We use programmable single-point lubricators for our hard-to-reach equipment bearings and regularly perform preventive-maintenance (PM) checks to ensure the units are working properly. Those PM checks recently detected that a number of newly installed units have failed to deliver any grease in weeks, despite a full charge of grease and the unit displaying active status. Is the unit at fault?”

Diagnosis:

All programmable single-point-lubrication (SPL) devices are similar in that they are predominantly designed to dispense grease into a single lubrication point, in a continuous manner, for up to two years on a single charge of lubricant. Programmable units are primarily battery-operated, self-contained units designed to operate using an electro-mechanical discharge pump or an electro-chemical reaction chamber that forces gas into a hermetically sealed expandable bellows chamber and “pushes” grease into the lube line.

Any of the following situations can cause the unit to appear functional in a “stalled” state of operation:

  1. The lube line carrying grease from the unit to the bearing point is blocked with debris or partially collapsed, causing line back pressure that will can stall the unit.
  2. The bearing has turned in the housing, creating a line blockage.
  3. The unit is operating outside in cold weather using a heavy #2 grease.
  4. The unit is set up on the longest delivery settings and has not been set up correctly prior to installation.

Prescription:

ALWAYS read the manufacturer’s instructions before using any SPL device. Many units are required to run on their shortest delivery cycle (full throttle delivery) for up to 12 or more hours to ensure the unit is working properly prior to set up and installation. And ALWAYS check that you have the correct NLGI numbered grease for the ambient operating temperature.

Moreover, when installing an SPL unit, make sure the delivery line has not been damaged or crimped in any way. MT

Ken Bannister of Engtech Industries, Inc., is a Lubrication Management Specialist and author of Lubrication for Industry (Industrial Press), and the Lubrication section of the 28th Edition Machinery’s Handbook (Industrial Press). For in-house ICML lubrication-certification training, contact him at 519-469-9173 or kbannister@engtechindustries.com

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