Lubrication - Motion Control Tips

Why is viscosity important for bearing lubrication?

January 10, 2019 By Danielle Collins Leave a Comment

Lubrication — or, more correctly, improper or insufficient lubrication — is one of the leading causes of equipment failures in industrial applications. Without it, sliding, rolling, or meshing surfaces experience significant friction, heat, and wear, leading to increased noise, loss of accuracy, and reduced equipment life.

One of the most important characteristics of a lubricant is its viscosity (or, in the case of grease lubricant, the viscosity of the base oil). But viscosity is analogous to friction in fluids. So why do you need friction (in lubrication) in order to reduce friction (in bearings)?

Tribology is the study and application of the principles of friction, lubrication, and wear between two surfaces in relative motion.

Viscosity = friction in fluids

Viscosity is a property of fluids and is caused by their internal resistance to shear. When a fluid is moving under laminar flow conditions, with no turbulence — as is the case with most bearing lubrication scenarios — microscopic layers of the fluid flow over one another, much like a stack of paper, with each sheet moving slightly faster than the one below it. Cohesive forces between these microscopically thin fluid layers must be overcome as the layers move past one another. The resistance caused by these cohesive forces is the primary determinant of the fluid’s viscosity.

In laminar flow, microscopic layers of fluid flow over one another. The layers’ internal resistance to this shear force gives rise to viscosity.
Image credit: Michael Fowler, virginia.edu

The role of viscosity in reducing bearing friction

Bearing surfaces, no matter how well they’re machined, finished, and cleaned, will always have asperities (peaks) and valleys. When two bearing surfaces are in contact (for example, ball and raceway or roller and raceway), the asperities of the surfaces interfere with each other. One of the primary roles of lubrication is to separate the surfaces and reduce or eliminate the interference of their asperities, which significantly decreases friction and wear.

But when the surfaces are stationary (or moving at very low speeds), the pressure between them essentially “squeezes” the lubrication from between the surfaces. There is a very thin lubricating film, but it is not sufficient to separate the asperities of the two surfaces, and significant contact still exists. This is referred to as boundary lubrication.

In boundary lubrication, friction, heat, and wear depend primarily on the interactions between the surfaces, although chemical reactions between the lubricant and the surfaces can also contribute to wear. The time spent in boundary lubrication conditions significantly affects bearing performance and life.

As bearing speed increases, lubrication is “pulled into” the contact zone.
Image credit: Wessex Petroleum Limited

As velocity increases, more lubrication is “pulled” into the space between the bearing surfaces, allowing a thicker lubrication film to develop. This causes the pressure on the lubrication film to increase, which, in turn, increases the lubricant’s viscosity (according to the lubricant’s pressure-viscosity coefficient). But there is a transition period where, as velocity increases, the surfaces are separated in some places, but in other places, interference between asperities still occurs. This is referred to as mixed lubrication.

Finally, when a sufficient velocity is reached, the lubricating layer becomes large enough to separate the asperities of the two surfaces, and the increased viscosity gives the lubricant sufficient film strength to support the load, by elastically deforming the bearing surface. This lubrication regime is referred to as elastohydrodynamic lubrication.

A Stribeck curve shows the development of the lubrication film and the resulting change in friction. As velocity increases, the bearing surfaces “pull in” more lubricant, creating a thicker lubricating layer under higher pressure, which results in higher viscosity. Finally, the layer is thick enough to separate the asperities of the surfaces, and the viscosity provides sufficient film strength for the lubricant to support the load.
Image credit: Anton Paar GmbH

Feature image credit: Exxon Mobil Corporation

Klüber Lubrication now sells grease for small gears subject to high loads

December 1, 2018 By Lisa Eitel Leave a Comment

Klϋber Lubrication, a worldwide manufacturer of specialty lubricants, introduces Klübersynth GE 14-151, a special grease for highly loaded small gears like those found in power tools.

This product consists of a finely balanced combination of ester and synthetic hydrocarbon base oils with an aluminum complex soap thickener. Klübersynth GE 14-151 has a wide service temperature range, good wear protection properties and a high scuffing load capacity. It also offers high protection against tribocorrosion.

Klübersynth GE 14-151 can be used to lubricate toothed wheels, bearings, joints and slideways. The optimized oil release behavior enables use in applications that are not sealed oil tight. With a high scuffing load capacity and good backflow behavior, the grease allows lubrication of gears with a high sliding ratio.

Depending on temperature, load and sliding speed, Klübersynth GE 14-151 can even be used on steel-steel, steel-aluminum, and aluminum-aluminum components. When used for lubricating trapezoidal and ball-and-screw spindles, it offers excellent wear protection and smooth running.

Klübersynth GE 14-151 can be used in gears operating at peripheral speeds of approximately 10 m/sec with a quasi-complete fill of the gear housing. It can maintain speeds of 20 m/sec over short-term or intermittent operation. Tooth flank lubrication allows a speed of 3 m/sec.

Klüber Lubrication is a manufacturer of specialty lubricants and high-end tribological solutions. Most products are developed and made to specific customer requirements. During its more than 80 years of existence, Klüber Lubrication has provided high-quality lubricants, thorough consultation and extensive services, which has earned it an excellent reputation in the market. The company holds all common industrial certifications and operates a test bay hardly rivalled in the lubricants industry. For more information, visit klueber.com.

Freudenberg Chemical Specialities Munich, was founded in 2004 as a new Business Group within the Freudenberg Group. Its objective is to promote innovation potentials in its field of activities and to expand world-wide market leadership in special lubricants and release agents. The Business Group includes five largely independent divisions which are active in more than 50 countries: Klüber Lubrication, Chem-Trend, SurTec, Capol and OKS.

New rail gearbox lubricant from Klüber Lubrication enhances cold-weather operation

November 8, 2018 By Miles Budimir Leave a Comment

Klüber Lubrication’s new Klübersynth LEG 4 75 W 90 is a synthetic high-performance gear oil for rail vehicle gearboxes. Even in the cold, trains need to run smoothly and these vehicle gearboxes often operate under high loads. The new polyalphaolefin-based oil technology of Klübersynth LEG 4 75 W 90 provides a wide service temperature range, including excellent low-temperature characteristics. Compared to conventional synthetic gear oils, its VI (viscosity index) enables a higher viscosity at lower temperatures.

Additionally, the good shear stability of Klubersynth LEG 4 75 W 90 prevents a decrease of the lubricant film thickness, even during long-term operation at high loads. The high micro pitting resistance protects gearboxes operating under high loads that are susceptible to this damage. Its low foaming tendency and anticorrosive properties make possible problem-free gear operation.

The high scuffing load capacity enables this gear oil to be used in gearboxes that require API GL-4 or API Gl-5. Its excellent wear protection of both gears and rolling bearings extends the life of lubricated components. The excellent aging and oxidation stability permit longer oil change intervals compared to mineral or other synthetic oils. Both of these characteristics reduce maintenance costs.

For maximum benefit, especially for the low-temperature range, Klübersynth LEG 4 75 W 90 can be paired with Klübersynth GE 4 75 W 90.

For more information, visit www.klueber.com.

How to specify motion components for cleanroom environments: Part 2

September 5, 2018 By Danielle Collins Leave a Comment

In this two-part article, we cover the products, materials, and features that designers and engineers should specify when choosing motion components for cleanroom environments.

In part 1, we looked at how to reduce particle generation due to friction between moving components. In this second part, we’ll look at another source of contamination — outgassing — and how to minimize it.

Objective #2: Minimize outgassing

Silicon wafer processing is extremely sensitive to contamination, including both particulates and outgassing.
Image credit: WaferPro

In cleanroom applications that involve the manufacture of LEDs, optics, or glass, or the processing of silicon wafers, a second type of contamination can damage the process or the product: outgassing.

Outgassing is the desorption of vapors or gasses, either from within a material or from the surface of a material. ISO standard 14644-8 addresses outgassing in cleanroom environments and specifically refers to airborne molecular contamination (AMC) as:

The presence in the atmosphere of a cleanroom or controlled environment of molecular (chemical, non-particulate) substances in the gaseous or vapor state that may have a deleterious effect on the product, process, or equipment in the cleanroom or controlled environment.

These types of airborne molecular contaminants take the form of molecular vapor. They’re smaller than particles and easily pass through HEPA and ULPA filters, making them particularly difficult to control once released.

Minimize outgassing through material selection

The first criteria when choosing motion components for cleanroom environments where outgassing is a concern is to ensure the material has a smooth surface, which makes it more difficult for airborne molecular contaminants to adhere to the surface. Stainless steel and anodized aluminum are the preferred materials, although some epoxy paints are suitable for environments where low-outgassing is required.

Fortunately, numerous motion control components, such as linear guides, motors, and gearboxes, can be made of stainless steel. When possible, plastic end caps on linear guides and screws should also be replaced with stainless steel versions to further minimize the use of plastics. And standard steel fastening hardware, such as screws or pins, should be replaced with stainless steel versions.

Although epoxy paint is sometimes suitable for motor and gearbox housings, stainless steel versions are better options.
Image credit: Wittenstein

When the required material has a high outgassing tendency, other solutions exist. For example, epoxy paint is suitable in some cleanroom environments and can be applied to the housings of linear actuators, motors, and gearboxes. And when steel is required — to maintain hardness, durability or load-carrying capacity — nickel plating can reduce the tendency of steel to outgas. (Note: Some nickel-plating formulas include a PTFE, or Teflon^®, top coat. The use of Teflon is generally advised against, so be sure to choose a nickel plating formula that does not include Teflon.)

Good: Nickel-plated steel, epoxy coated aluminum
Better: Stainless steel or anodized aluminum; minimal use of plastics
Look for: Smooth surfaces (no textured paints)

Reduce outgassing from lubricants

A wide variety of cleanroom-rated lubricants are suitable for bearings, motors, gearboxes, and other motion components.
Image credit: NSK

When it comes to outgassing, lubricants are one of the major offenders, readily spewing molecules of water and oil vapor into the atmosphere. Unfortunately, in the majority of motion systems, the use of components that require lubrication simply can’t be avoided. When lubrication is required, ensure the lubricant is suitable for cleanroom environments. Cleanroom compatible formulas that minimize outgassing while protecting bearing surfaces from rust and friction are widely available.

Good: Cleanroom-rated lubricants
Look for: Opportunities to minimize the need for lubrication through component selection

Feature image credit: Lin Engineering, Inc.

How to specify motion components for cleanroom environments: Part 1

August 29, 2018 By Danielle Collins Leave a Comment

In this two-part article, we cover the products, materials, and features that designers and engineers should specify when choosing motion components for cleanroom environments. In part 1, we look at how to reduce particle generation due to friction between moving components.

Designers of automation systems are tasked with many competing demands, such as balancing cost and performance, fitting motion components and systems into existing machine or process layouts, and designing for ease of manufacturing and assembly — to name a few. But when the system is to be used in a cleanroom, an additional layer of complexity is added, requiring designers to choose products that won’t degrade or compromise the cleanroom environment.

The level of “cleanliness” of a cleanroom is determined by the number of particles, broken down into six size ranges, that are present in a specified volume of air. In the United States, Federal Standard 209E is often used for cleanroom ratings, although it was officially canceled in 2001. This standard specifies cleanroom levels from 1 (best) to 100,000 (worst) in multiples of 10.

The current, and more universally-accepted, standard is ISO 14644-1, which defines cleanrooms on a scale from 1 (best) to 9 (worst). Each of the ISO classifications has a corresponding FS 209E level, with the exceptions of ISO classes 1 and 2, which are higher (better) than the highest FS 209E classification, and ISO class 9, which is lower (worse) than the lowest FS 209E classification.

ISO standard 14664-1 rates cleanrooms on a scale from 1 (best) to 9 (worst). Federal Standard 209E uses a scale from 1 (best) to 100,000 (worst) based on the number of allowable particles greater than or equal to 0.5 micron.
Image credit: Mecart Inc.

Objective #1: Reduce friction

One of the two primary sources of contamination, or particles, that can degrade a cleanroom environment is friction from moving components. (The other source is people.)

Virtually every motion system involves some amount of friction between sliding or rolling surfaces — whether from linear bearings, rotary bearings, or meshing gears. And when there is friction, particles are generated. Therefore, when specifying motion components for cleanroom environments, reducing friction should be the foremost objective.

Linear guides and drives

To minimize friction from linear guides, choose rolling contact rather than sliding contact and, when possible, avoid systems with high preload. For example, a non-preloaded miniature rail guide that uses two rows of recirculating balls emits significantly fewer particles than a preloaded standard guide with four rows of recirculating balls. And because there’s little chance of the bearing experiencing contamination in a cleanroom environment, use linear guides with low-friction or non-contact type seals.

Air bearings are another, although less common, method for guiding and supporting loads. In cleanroom applications, however, air bearings are often the best choice for low particle generation, since they are completely non-contact devices.

When it comes to linear drives, belts and chains should be avoided in cleanroom applications, due to the significant contact and wear they experience. Similarly, the meshing of gears in rack and pinion systems cause high friction and wear, so these should also be avoided. This means that ball screws are typically the default choice for linear drives in cleanroom applications.

However, ball screws require lubrication, and the rotation of the screw can cause lubrication to “sling” or “splatter,” contaminating the cleanroom environment. Using low-friction or non-contact seals (see above) will help keep the lubrication inside the ball nut and protect the cleanroom.

Like air bearings for linear guidance, linear motors provide a completely non-contact option for driving the load. But in their traditional setup, linear motors operate with the forcer (primary part) moving. This means the cables must move as well, and as we’ll discuss below, cables are another source of particle generation. A better configuration for cleanroom applications is to keep the forcer (primary part) and its cables stationary and allow the magnet track (secondary part) to move.

The combination of air bearing guides and a linear motor drive in this ABL 2000 stage from Aerotech provides completely non-contact movement, ideal for cleanroom applications.

Good: Rolling contact (rather than sliding contact) guides and drives
Better: Air bearing guides and linear motors
Look for: Low-friction or non-contact seals; cleanroom lubrication

Cables and cable management

Another source of friction and, therefore, particle generation, is the cable management system, including the cables themselves. Traditional round cables can generate particles when they rub against each other or against parts of the cable track. The best way to reduce particulates from cables and cable management systems is to use components and system design practices that reduce the amount of cabling required — for example, using an integrated motor-drive system instead of separate motor and drive components.

Cable carriers used in cleanrooms should have low vibration, low-abrasion fastening, and smooth interior surfaces to prevent abrasion of cables.
Image credit: igus Inc.

For the power, feedback, and data cables that are necessary in a motion control system, manufacturers offer cable designs with special low-friction coatings to minimize particulates and reduce outgassing. Similarly, several cable track manufacturers offer systems that reduce wear between chain sections through the use of abrasion-resistant joints. And for shorter lengths, so-called “trackless cables” are self-supporting flat cables that don’t require a cable track or carrier.

Trackless cables are self-supporting and don’t require cable carriers.
Image credit: W.L. Gore & Associates, Inc.

Good: Round cables with anti-friction coatings; cable carriers with abrasion-resistant joints
Better: Self-supporting flat cables
Look for: Opportunities to reduce cabling

Rotating equipment: motors and gearboxes

When it comes to rotating equipment in motion applications, the bad news is, motors and gearboxes use rotary bearings, and gearboxes require meshing teeth — all of which are sources of friction and particle generation. The good news is that these components are enclosed, so particles are less likely to “escape” and contaminate the cleanroom environment. And there is a wide range of cleanroom-compatible lubricants that can be used in the high-speed, high-load conditions found in motors and gearboxes.

To improve cleanroom compatibility, it is also possible to add a slight vacuum to the motor or gearbox housing. The vacuum serves to extract and remove particulates so they don’t have an opportunity to contaminate the cleanroom. Note that vacuum purge is also a good option for enclosed actuators that have a static (non-moving) seal. Although the enclosed design tends to keep particles inside the actuator, adding vacuum purge helps to achieve higher levels (class 100, 10, or 1) of cleanroom compatibility.

Vacuum purge is an effective way to ensure particulates from closed systems, such as this linear actuator, don’t have a chance to escape and degrade the cleanroom environment.
Image credit: THK Co., Ltd.

Good: Fully enclosed housings
Better: Vacuum purge
Look for: Cleanroom grease options

In part 2 of this article, we’ll look at another source of contamination — outgassing — and how to minimize it.

What’s unique about worm gear lubrication?

December 12, 2017 By Danielle Collins Leave a Comment

Worm gears are used in various types of applications for their ability to provide very high reduction ratios and, in many cases, for their self-locking properties. But choosing the right worm gear lubrication involves more than just selecting the right viscosity.

In a worm gear assembly, the worm is typically made of steel and the gear is made of bronze.
Image credit: Framo Morat

Most gear types, such as helical, bevel and spur, experience both sliding and rolling contact as the teeth engage and mesh. But worm gears operate with mostly sliding contact between the worm and the gear (also referred to as the “worm wheel”). This predominantly sliding contact results in significant friction and very high operating temperatures. It also makes the formation of a hydrodynamic lubrication wedge, or film, difficult, so the gears operate predominantly under boundary lubrication conditions. A result of these combined operating factors is that worm gears require lubricants that can operate under significant heat and pressure, in addition to providing excellent lubricating properties.

Lubricants with extreme pressure (EP) additives seem to fit the bill, but there’s a catch: EP additives often contain activated sulfur or chlorine, both of which can damage yellow metals through softening or etching. (Most worm gears are made of a steel worm and a bronze gear.) To reduce these harmful effects, some EP lubricants now use deactivated sulfur.

In the quest to find a lubrication that can withstand the operating conditions of worm gear assemblies, without reacting with the bronze gear, some manufacturers and lubrication specialists recommend using compounded oils, which are made from a mineral oil base with acidless tallow or fatty acid, and with rust and oxidation inhibitors added. Compounded oils provide better lubricity, which reduces friction and wear. However, they have a temperature limit of approximately 80° C (176° F). Above this temperature, oxidation increases rapidly and produces acidic products that can damage the bronze gear.

Synthetic lubricants are another alternative, and although they have a higher up-front cost, they can noticeably improve the efficiency and operating life of worm gear assemblies. These usually fall into two categories: polyalphaolefin (PAO) and polyalkylene glycol (PAG) synthetic oils. PAOs have lower viscosity and a high viscosity index, so they can be used in a wider range of temperatures. Most have anti-wear additives, and PAOs are available with EP additives.

Similarly, PAGs have a high viscosity index and a wide operating temperature range. They also have superior lubricity properties when compared to other types of lubrication. PAGs contain anti-wear additives, but unlike PAOs, PAG synthetic oils are not available with EP additives. And they tend to be incompatible with paints, seals, and polycarbonates.

Using the wrong type of lubrication and not providing sufficient lubrication are two of the most common causes of worm gear failure.

In addition to choosing the right type of lubricant, ensuring that the worm gear has the right quantity of lubricant is critical to proper operation. Worm gears are typically lubricated by the splash method, and another unique characteristic of worm gear lubrication is that the mounting orientation plays a significant role in determining how much lubrication is needed.

In the worm-under orientation (right) the gearbox assembly requires as much as 50% more lubrication than in the worm-over orientation (left).
Image credit: Altra Industrial Motion

Case in point – worm gears are most commonly mounted in the worm-over orientation, where the worm sits above the gear, but they can also be mounted in a worm-under orientation. To ensure that it’s properly lubricated in the worm-under orientation, the gear assembly requires up to 50 percent more lubricant than in the worm-over orientation.

Feature image credit: Precision Technologies Group

Power-transmission components and mechanical systems see three new trends

May 4, 2017 By Lisa Eitel Leave a Comment

Power-transmission (PT) components include essentials such as chain, springs, seals, and retaining devices, to name a few. There are three main trends that have dominated recent innovation in their design and application. New materials in mechanical parts continue to expand the applications in which all components operate effectively. Compression and wave springs are specified in more customized versions than ever, tying to a larger move away from off-the-shelf components. Finally, demand for longer life is spurring advances in lubrication to 21st-century formulations.

In fact, all mechanical designs must satisfy ever-changing industrial design needs, but here we detail advances that industry professionals see dominating these power-transmission assemblies.

Here Kevin McBarron at Nye Lubricants adjusts pins for an electrical-connector application test. Five engineers work in the 2,200 ft2 ADVT lab. Through their experience and knowledge, the supplier can now can model and simulate applications and make computational simulations for performance prediction. this lets Nye run three types of tests, depending on project needs — modeling and simulation, component testing, and practical testing.

IoT on belt drives and digital design help elsewhere

Internet of Things (IoT) and Industry 4.0 functionality is touching even mature power-transmission technologies to boost design performance.

“The rising tide of IoT could mean that larger (and more mission-critical) power-transmission drives could soon include widespread placement of sensors,” said Arron Ryan, product engineer at Thermoid, manufacturer of rubber products including belting and hose. “On conveyor belting as well as power-transmission belting, the sensors would fit onto pulleys to measure performance and wear factors — including changes in groove ride height and rates of efficiency,” Ryan continued.

There are already sensor systems available (albeit at higher price points) that can capture inputs such as run time, temperature, and vibration. “But technology enhancements such as this on a large scale could soon provide designers of drives with big data to design longer-lasting products with higher efficiencies and reduced maintenance,” Ryan of Thermoid concluded.

Another form of improved service from digital data is the proliferation of online configuration tools. These are changing how design engineers specify all offerings in the power-transmission and motion-control space — in part because service expectations in the industrial market are ultimately influenced by what’s come to be expected from the consumer market.

“Online configurators for clothing and other consumer products give users quick leadtimes and the ability to get price and delivery without ever talking to someone. Now these B2C online-purchasing trends are informing the design of configuration tools that have become integral to the B2B engineering-design process,” said Mike Parzych of GAM Enterprises.

Right now, a GAM online sizing tool lets engineers specify components that are compatible with their servomotor. The tool is integrated with an online catalog and CAD configurator. The manufacturer is also looking to add options and customizable capabilities to the latter. “Our products are configurable, and we want our models to reflect that,” said Parzych.

Visit linearmotiontips.com and read our trends piece on online configuration tools for more on what’s on the horizon here.

New installations for retaining rings and wave springs

Over the last several years, there’s been a slow trend to replace threaded fasteners (and the tapping and drilling they entail) with retaining rings. These fasteners installed into assemblies at preset shaft or housing grooves that function as shoulders to keep an assembly together. What’s more, material advancements continue to improve these as well as other spacers, pins, and washers.

Coatings of zinc thermal diffusion weren’t commercially viable for small components until recently. Now processes and equipment from SPIROL allow for this coating on small mechanical parts and fasteners. Shown here is a base layer of a part followed by alpha, gamma, delta, and zeta layers of the sacrificial zinc coating. Notice the uniformity.

Case in point: Finishing with affordable zinc thermal diffusion is better than ever for finishing parts with a sacrificial surface of zinc-iron diffusion. Now mechanical-component suppliers are applying one newer patented version of the process called ArmorGalv. Fastener company SPIROL is one adopter.

In short, ArmorGalv coating applies at 650˚ F or higher in a closed chamber. The part bakes in a closed environment filled with zinc vapor. Soluble in iron, the zinc diffuses into the ferrous part in a near-zero-emissions process. The coating is anodic to steel, so makes for long-lasting galvanic protection. After baking, sometimes the parts get additional application of sealant. Benefits include anti-galling, uniform coating, and no embrittlement.

Another trend affecting fasteners is the unabated drive towards miniaturized designs. This forces the shrinking of assemblies — including all their fasteners and compression and wave springs. Consumer electronics and medical-device industries are driving much of the innovation in this department.

In some cases, simply switching to compact compression springs or from conventional helical-wound springs to wave springs in sufficient. That’s because these apply more load for a given volume — which is useful in the tight spaces inside implantable medical devices, for example. In fact, even disposable surgical applications are driving engineers to design smaller instruments, as there’s more interest than ever in making surgeries less invasive. That’s turning many inpatient procedures to outpatient procedures — a win for all.

Behind some of this is how technological advances now let developers make wave springs smaller than 0.250 in. in diameter … enabling smaller tools in other industries as well. Even cordless drills and other consumer power-tool designs benefit.

Bespoke lubrication formulas (and mechanical design) for better PT performance

Some lubricant suppliers are looking to solve mechanical challenges from the tribological front — and they’re taking cues from an industry that’s increasingly service-oriented. “Several years ago, a new concept was born within our technical organization,” said Jason Galary, engineering development and applications manager at Nye Lubricants. The idea was to create technical competency and functionality for bridging a gap between R&D and product development. “This new functionality focuses on developing a better understanding of the fundamentals of applied tribology and combining this with simulations of customer applications,” explained Galary.

Here Jason Galary and Gus Flaherty of Nye Lubricants study data from their laboratory’s particle-generation tester. The ADVT lab is Nye Lubricants’ response to the trend towards increased in-house engineering expertise and support through collaborative efforts with end users to solve tribological problems.

Usually in industry, the supplier identifies or develops lubrication solutions for the OEM or end user, and then ships lubricant samples out to the customer for testing. Such tests are based on physical property data and the experience of technical support and sales engineers. But such an approach burdens the OEM or user with testing and upfront cost. “We moved away from this by creating Nye’s Applications Development and Validation Testing (ADVT) group,” explained Galary.

The ADVT lab now focuses on two modes of testing — component testing (and simulation) as well as applied mechanics.

“Through stronger understanding of how lubrication systems function in dynamic applications, we can more accurately predict performance and supply better lubricant,” said Galary. This helps users trim research, development, and testing time, in turn reducing product cost.

Consider one example for the semiconductor-manufacturing industry and how the lubricant supplier developed a particle-generation test method and apparatus.

Here, Kevin McBarron of Nye Lubricants lubricates a shaft for a steering system. Component testing is just one form of partnering to trim lubrication development time and cost for users. Recently, Nye designed a simulation rig around a full-size electronic power steering (EPS) system from customer specifications. Working with the parts manufacturer to develop an accelerated endurance test, the lubricant supplier devised a new formula to meet performance goals and boost system life and quality — so the tribological test validation was satisfied, and the manufacturer could focus development elsewhere.

“The thought of particle generation is one that haunts many engineers’ minds, especially if they’re working on applications in the vacuum industry,” said Galary. Foreign particles of unknown or dubious nature drifting through the air (or traveling through vacuum) might deposit on critical areas such as a semiconductor fab, and cause extremely costly problems as a result. “But our new test method measures the amount of airborne particulate generated by a lubricant from rolling contact as in a ballscrew or bearing,” said Galary. “That lets us classify a grease to an ISO or federal air-cleanliness standard.” That in turn lets users know just how many particles are being generated in their cleanroom, so they can pick a material to match their cleanliness requirements.

In fact, it’s not just the formulation of lubricants. All motion-component suppliers we surveyed mentioned some expansion of in-house engineering support. Some who supply mechanical-design services base much of their business on it — mostly to eliminate problems associated in the past with integration.

More motion-component suppliers than ever (including GAM Enterprises) act as extensions of customers’ engineering departments by helping them eliminate components, save space, and boost design performance. Listed here are some ways in which GAM components improve the design of one lift system.

“Customization is in GAM’s DNA. Our mission is to give customers what they want, even in small batches and at a value,” said Craig Van den Avont, president at GAM Enterprises, manufacturer of gear reducers, couplings, linear-mounting kits, and other automation products. The manufacturer works with design engineers to understand their application, requirements, and machine assembly. Then it seeks ways to combine or modify standard products (or manufacture other components) so OEMs or end users can build a better machine or optimize to application requirements.

“We’ve had to align all our business functions to properly support these projects,” said Van den Avont. Last year for example, the company expanded in-house manufacturing capabilities with customization and flexibility in mind. “Ultimately, we act as an extension of our customers’ engineering departments by helping them eliminate components, save space, reduce costs, and increase machine performance,” added Van den Avont.

Wayne Products introduces intermittent-use oil skimmer

January 23, 2017 By Lisa Eitel Leave a Comment

Wayne Products now sells a Mini-Skimmer R.S., a belt-type oil skimmer that collects over a quart of oil per hour despite its tiny housing that measures just 3 x 3 x 2.75 in. Designed as an easy-to-use solution for small machine shops, Mini-Skimmer R.S. skims unwanted tramp oils from coolants, but can rest easily with the flip of a switch once its job is complete.

Named after Rich Segermark, the company’s founder and inspirational innovator, Mini-Skimmer R.S. is the smallest of Wayne Products’ expanding family of oil skimming products.

It is the only oil skimmer on the market with an on/off switch, allowing users to easily monitor its activity, and is lightweight and small for seamless transportation between machines.

The design of Mini-Skimmer R.S. emphasizes ease of use, knowing that smaller machine shops sometimes need a small, simple product that is portable, yet effective. Mini-Skimmer R.S. comes with the company’s industry-standard, stretch-resistant, fiberglass-reinforced cogged belt but has a liquid tight housing made of anodized aluminum and a motor with the highest torque for a skimmer of its size. It is also shipped completely assembled – just plug it in and flip the switch.

“This oil skimmer is the perfect solution for small machining operations. It has been designed from scratch to address key customer needs while hitting a price point previously unattainable,” said Don Ware, President of Wayne Products.

Wayne Products offers industrial customer base an affordable product. Expect the company to continue to develop new products in the future as it fulfills its mission of providing the best and longest-lasting products to its customers.

Wayne Products has manufactured Mini-Skimmers and Maxi-Skimmers since 1989 from its facility in Broomall, PA. They also manufacture Electra- Kool Filtered Blowers for use on electrical enclosures and electric motors. Visit www.miniskimmer.com for more information.

Motor: 15.5 rpm permanent magnet synchronous motor with 8 oz-in. of torque; die-cast gear housing, cut brass gears, class F insulation, UL/CSA recognized, 115/1/60, draws 0.011 A

On/off switch: rubber-booted, 6-amp toggle switch. housing: 6061 aluminum, clear anodized, sealed with nitrile gaskets

Tension bar: 6061 aluminum, clear anodized, with height-depth adjustment

Mounting bracket: 14-gauge type 304 stainless steel

Scraper or trough: electro-polished, 24-gauge type 304 stainless steel.

Belt: fiberglass-reinforced oleophilic polyurethane belt with MXL teeth. non-static & non-stretch

Pulleys: corrosion-resistant, double-flanged, glass-filled nylon with stainless set screw

Power cord: 18 gauge, grounded 8-foot SVT with three-pronged plug, CSA/UL rated, NEMA 5-15p

Strain relief: plastic submersible cord grip with rubber o-ring, nema 4x & ip68 rated

Klüber Lubrication introduces water displacement fluid

July 18, 2016 By Lisa Eitel Leave a Comment

Klüber Lubrication, has introduced Klüberfood NH1 4-002 Spray, a water displacement fluid that is available in an aerosol spray for convenient application. The spray can be used as a penetrating oil to prevent seizures, for example, in the case of a thread and bolt. The oil can also protect metal machine surfaces subject to periodic wash downs.

The lubricant was developed for use around products and packaging materials in the food production and pharmaceutical industries. Klüberfood NH1 4-002 Spray is NSF H1 registered, and is therefore acceptable as a lubricant with incidental food contact for use in and around processing areas.

In addition to food quality assurance, the use of Klüberfood NH1 4-002 Spray can also lead to an increase in reliability of production processes. The product is able to reduce staining and corrosion of metal machine surfaces through water displacement. By working to prevent seizure, the oil also contributes to a reduction in downtime during assembly and disassembly of machine components.

Klüber Lubrication
www.klueber.com

How to choose an industrial lubricant

June 2, 2016 By Motion Control Tips Editor Leave a Comment

by Bill Watson, Director of Application Engineering, Klüber Lubrication NA LP

Choosing the right lubricant for an industrial power-transmission design can be a tricky task, because industrial lubricants come in many varieties and formulations, and many industries require lubricants that adhere to specific regulations and standards. Here are some tips to make the selection easier.

For decades, lubricant suppliers have been developing and manufacturing specialty lubricants tailored to the requirements of industrial applications. There are general technical requirements that all lubricants must meet, including the reduction of friction and wear, protection against corrosion, dissipation of heat and sealing. But, depending on the operating conditions and manufacturing processes in the plant, lubricants may also be expected to provide a host of additional properties.

Before selecting an industrial application, consult a supplier who can help answer key questions about the design. In the case of a chain drive, ask: Will the installation need to survive an outdoor environment? Will the chain be subject to infrequent service? Lubricants exist to help chain and other power-transmission components last for years in even the harshest machine setups.

General purpose or synthetic lubricants?
One of the first questions a lubricant supplier should ask is if the equipment’s lubrication will be maintained at regular intervals or if it must be lubricated for life. The answer to this question helps determine whether the use of a general purpose lubricant or a synthetic specialty lubricant is more appropriate.

Oils, greases, pastes and waxes, and bonded coatings are the most common categories of industrial lubricants. Typically, an oil lubricant contains 95% base oil (most often mineral oils) and 5% additives. In contrast, greases consist of lubricating base oils that are mixed with a soap to form a solid structure. Pastes contain base oils, additives and solid lubricant particles. Finally, lubricating waxes consist of synthetic hydrocarbons, water and an emulsifying agent, which becomes fluid when a certain temperature level is exceeded.

Kluber-bertherm-HB-8-182-lubricant-for-olling-bearing

Greases (as that on this bearing) consist of lubricating base oils that are mixed with a soap to form a solid structure. Pastes contain base oils, additives and solid lubricant particles. In contrast, lubricating waxes consist of synthetic hydrocarbons, water and an emulsifying agent. Work with the supplier to determine which is most appropriate.

The majority of oil lubricants, including many motor oils, are mineral oil distillates of crude oil (petroleum), while synthetic oil lubricants are also used. Synthetic oils such as polyalphaolefins (PAOs) or synthetic esters are produced artificially from other compounds. Because of this, the composition is quite different from petroleum oil. Their higher purity and uniformity provide for several enhanced properties, such as viscosity index, oxidation stability and color.

There are also semi-synthetic oils (also called synthetic blends), which are a blend of mineral and synthetic oil. This class of lubricants provides many of the benefits of synthetic oil at a fraction of the cost.

When synthetic oil is selected, it is generally to provide mechanical and chemical properties superior to those found in traditional mineral oils. When a manufacturer does not stock an appropriate synthetic lubricant with the performance features needed for a given power-transmission application, that design may necessitate a customized specialty or ‘optimized’ lubricant.

If the equipment will be regularly lubricated, synthetic or specialty lubricant designed to last for an extensive period of time is usually unnecessary. In this case, the lubricant needs only to meet basic performance standards and be replenished regularly.

On the other hand, if equipment is lubricated for life, synthetic base oils are often recommended for their many benefits:

• Low and high-temperature viscosity performance
• Decreased evaporative loss
• Reduced friction and reduced wear
• Improved efficiency
• Chemical stability and resistance to oil-sludge problems
• Extended drain intervals

Despite their many benefits, synthetic lubricants are also known for one distinct disadvantage of cost. But the cost may be mitigated by extended change intervals, as synthetic and specialty lubricants can last five times longer or more than non-synthetic lubricants when a high-quality base oil is used.

Some synthetic or specialty lubricants are 50 to 500% more expensive than general-purpose lubricants, but price per pound or kilogram should not be the only determining factor in selection.

Factors that influence selection
The key requirement for selecting the proper lubricant is the base oil viscosity. In order to select the appropriate viscosity, the lubricant supplier will need to gather key information about the application at hand:

• Axis operating speed (variable or fixed)
• Specific type of friction (such as sliding or rolling)
• Load and environmental conditions
• Industry standards

For example, some lubricants such as PAG (polyalkylene glycol) oils are good for sliding friction, but are unsuitable for rolling friction. Likewise, PAO oils are used for rolling friction and can handle some sliding friction, whereas silicon and PFPE lubricants are typically used for extremely high temperatures.

Common mistakes in lubricating power-transmission components
During the information-gathering stage, equipment owners often make the mistake of overlooking some basic application details which can have a significant impact on the resulting lubricant’s performance. It is important to provide as much information as possible and to be specific, as this will help the design-engineering team and supplier identify the lubricant best suited to the task.

Another common mistake equipment owners make is choosing a lubricant based solely on price. Admittedly, there is a vast difference in the price of a synthetic or specialty lubricant and a general purpose lubricant. Some synthetic or specialty lubricants are 50 to 500% more expensive than general-purpose lubricants, but the price per kilogram should not be the only determining factor in selection.

Additional factors to take into consideration are:

• Reduced operating costs resulting from less downtime
• Improved labor utilization (as there’s less time required for re-lubrication and maintenance)
• Measurable energy savings and increased output

Often, when a supplier makes a lubricant recommendation for a particular application, and that application is successful, the customer wants to use the same lubricant in another application. Unfortunately, this is typically not an option. Remember, every application is different, and while one lubricant may work well for a ball bearing application, it likely will not provide the same performance for a different bearing application.

Ultimately, the first step in choosing the right lubricant is choosing the right lubricant supplier. Look for a supplier to provide quality documentation and detailed test data that demonstrate the consistency and quality of the product being recommended. A reputable supplier will spend time educating design teams so they can make qualified decisions about lubricating equipment.

Reprint info >>

Klüber Lubrication
www.klueber.com