Ideal for HVAC plant maintenance departments and service contractors, the Split uKIT is designed to accommodate shaft shoulders, slingers and other end bell protrusions. The halves of its split AEGIS ring are held together by a unique hinge, which permits the split AEGIS ring to be easily opened on one side. It is then closed and fastened together with an integrated adhesive-backed aluminium tabs, offering rigidity to the assembled ring.

The kit, which is ordered based on the frame size of the motor, includes the correct size split AEGIS grounding ring as well as the mounting hardware, such as washers, screws, four kinds of brackets and Allen wrenches, for use in various combinations for easy mounting of the ring on any IEC or NEMA motor faceplate.

AEGIS® rings prevent costly motor replacements/repairs, downtime and electrical bearing damage by channelling VFD-induced bearing currents safely to the ground. Its conductive microfibers are securely embedded in continuous circumferential rows in the ring’s patented AEGIS FiberLock channel, surrounding the motor shaft completely while providing harmful shaft currents with numerous discharge points. Creating the path of least resistance, this unique design effectively redirects the currents away from the bearings to the ground. To prevent breakage and minimize wear, the microfibers have been specially developed for exceptional flexibility and conductivity.

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A graphite/metal alloy, GRAPHALLOY is specifically developed to operate without lubrication, making it suitable for operations in environments with temperatures exceeding 750 degrees F (400 degrees C). A proven solution even for the most demanding plant maintenance as well as new equipment design, GRAPHALLOY is an excellent choice for applications where maintenance and service tasks are difficult or cumbersome.

Intended for use in standard flange and pillow blocks, GRAPHALLOY 845 Spherical Inserts eliminate the need to redesign or alter the equipment. These new spherical inserts are utilized in various high temperature applications such as ovens, conveyors, furnaces, dampers, glass lehrs, dryers and in other environments where grease and oil cannot be used. Stainless steel housing and metric shaft sizes as well as inserts are offered along with FDA accepted grades.

“Using GRAPHALLOY® 845 Spherical Inserts has proven time and time again that significant ROI, cost savings and reduced maintenance can be achieved, especially in difficult applications where high temperatures are a concern,” said Eben Walker, General Manager of Graphite Metallizing Corporation.

Offering dimensional stability and low coefficient of friction, GRAPHALLOY 845 Spherical Inserts do not soften even at high temperatures nor extrude under load.

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“These imperial housed tapered roller bearing units were the missing segment from BMG’s housed bearing product portfolio. The addition of this product range by one of our key supply partners enables BMG to better satisfy customer demand,” said Rouff Essop, Bearings Division Manager at BMG.

Designed for extended service life and efficient performance in demanding environments, the QMSN series is developed with cast steel housing that offers three times the cast-iron housing’s tensile strength. The robustness of the spherical roller housed unit allows the bearing to be replaced several times.

These units are ideal for use in aggregates and mining operations, including in automotive, oil and gas, steel, agriculture and power generation industries. The new series is also suitable for use in saw mills, treatment facilities, pulp and paper industry as well as in food and beverage industry.

The QMSN series offers three standard sealing options — the triple lip Viton rubber series, Teflon labyrinth seals and the triple lip nitrile rubber series.

Aside from the units’ standard locking method, they also feature eccentric collar. Unlike the ball bearing housed units’ eccentric collar, the QMSN’s collar comes with a shallow ramp when it is rotated to the inner ring. Moreover, the axial contact area’s angle between the inner ring and the collar is bigger than normal, effectively preventing the locking mechanism from loosening.

The series alternative locking methods include a tapered sleeve lock with a standard adaptor sleeve arrangement, a grub screw lock and the new V-lock, which encompasses a double taper locking method.

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Aimed at low-load applications, the new iglidur N54 plain bearing uses polymer that is mainly made of castor oil, rather than crude oil, which is commonly used in plastic bearings.

“The introduction of our iglidur N54 biopolymer marks the first serious step towards ‘green bearings’,” said Matt Aldridge, Director of IgusUK.

He noted that the biopolymer “is made from crop oil instead of crude oil – you can’t eat it, and it’s not biodegradable – but it is an industry first for a technical polymer.”

The new plain bearing is both maintenance and lubricant free, and in-house test results showed that the new material has up to 2MPa of wear resistance properties for loads. Furthermore, the iglidur plastics weigh less than any other metallic version; with the average weight is only 1.4 g/cm3 compared to steel, which weigh by as much as 5.5 times.

As the new bearing does not require any grease and oil, it cannot discharge any contaminants into the environments. In addition, the energy needed to create plastic bearings is remarkably less compared for producing metals.

The European Bioplastics Association also noted that the global production capability for biopolymers will surge from about 700,000 tonnes last year to approximately 1.7 million tonnes by 2015.

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Since the launch of the first Dodge Type E bearings in 1938, the range has been continuously improved to meet the changing demands of industrial customers. This innovation is continued with the addition of the newest Dodge Type E-Xtra bearing. It has been specifically designed with features that will ensure optimum performance with outstanding reliability.

The US-made high capacity tapered roller bearing insert permits a combination of thrusts and radial loads, producing the industry’s highest load ratings. Lab tests prove that the latest tapered insert offers 13 percent to 14 percent increase in ratings than the previous insert. It features a carburized inner ring that can resist cracking and absorb shock.

The new bearing comes with XTS triple-lip seal, a state-of-the-art system that protects the bearing from contamination in wet or dusty environments, while the oversized dual Springlok collars serve as flingers for added seal protection. Customers can also opt for the XTS Plus sealing system, which is integrates the Dodge E-Tect seal kit for additional protection, making it suitable for extreme conditions.

For easy installation, the bearings have been pre-lubricated, preassembled and factory adjusted. They are also offered in various configurations, including two- and four-bolt pillow blocks, piloted flanges, flanges, wide slot take-ups and top angle take-ups. They are also available in imperial and metric versions.

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The basic concept behind a bearing is that things roll more easily than they slide. This could be explained by the fact that when surfaces slide, the friction between the two objects generates a force that slows them down. However, friction can be significantly reduced if the two surfaces are able to roll over each other.

Bearings minimize friction by providing smooth rollers or metal balls, as well as a smooth outer and inner metal surface that the balls can roll against. These rollers or balls “bear” the load, enabling the device to spin smoothly.

Bearings normally deal with two types of loading, thrust and radial. Depending on what type of application they are used in, bearings may experience all thrust loading, all radial loading, or both.

For instance, the bearings in an electric motor and a pulley face radial load only. This is because the load originates from the tension of the belt that connects the two pulleys. The bearing in a barstool is loaded primarily on thrust, as the load is attributed to the weight of the individual sitting on the stool. Meanwhile, the bearing in the hub of a tractor wheel supports both a thrust and radial load. The weight of the tractor provides the radial load, while the cornering forces produced when the operator makes a turn present the thrust load.

There are many types of bearings, each of which is used for varying purposes in different applications.

A roller bearing, which is a weight distribution-oriented bearing, is any spherical or cylindrical object that helps an object larger than the bearing itself move. It uses various contact points between a circular housing containing internal rolling elements. These bearing systems use the reduced rolling resistance to increase the moving object’s efficiency.

Roller bearings commonly help two or more items reduce the amount of friction between them. An example of this is a simple wheel and axle. The roller bearings allow the wheel to freely spin on the axle without being limited by friction. They also reduce the force of drag on the spinning wheel, enabling the wheel to be easily pushed by any power source, such as an engine or a person pushing a vehicle.

There are numerous types and designs of roller bearing systems that may be used in various applications.

Cylindrical roller bearings, for instance, comprise a metal collar containing a smaller, toothed wheel inside. A ball bearing lies in between each of the wheel’s teeth, while the toothed wheel holds it in place. Thus, the wheel turns as the load travels, but the load’s weight remains directly fixed over the spherical ball bearings within the cylinder, enabling the easy movement of the load.

Roller thrust bearings usually support large thrust loads and are often found in gearsets such as vehicle transmissions between gears, rotating shafts and the housing, while tapered roller bearings are a kind of bearing that can support large thrust load and large radial load. They are used in car hubs and often mounted in pairs facing opposite directions, allowing them to handle thrust in both directions.

Meanwhile, ball bearings or anti-friction bearings are used to minimize friction between axles and shafts in numerous applications. Comprised of small ceramic or metallic spheres, ball bearings are commonly used in a series, absorbing the weight placed on the moving part. Most ball bearings are developed to meet very demanding standards of roundness and any deformation may cause the unexpected failure of the moving parts.

Spherical bearings are generally used in pivoting, high-load applications where angular misalignment is required. They allow angular rotation around a central point and often support a rotating shaft that is rotating at an angle. They may be employed in steering linkage suspensions on vehicles, articulated joints on heavy equipment, hydraulic cylinder rod ends, and other similar severe-duty uses.

Linear motion bearings are specifically designed to allow motion in one direction, such as on a linear slide. With these bearings, the rolling contact is provided by hardened and ground balls. A linear ball slide is a compact form of linear bearing with a small form factor and a similarly short stroke. Stroke can be a maximum of about one-third of the slide length, but the form factor justifies the stroke.

Magnetic bearings are used in some very high-speed devices, such as advanced flywheel energy storage systems. These bearings enable the flywheel to rapidly rotate on a magnetic field produced by the bearing.

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Bushings provide possibly the simplest linear bearing. These thin-walled cylinders can be injection molded of proprietary polymers infused with a lubricant. An oil-infused bronze design, also cylindrical, rides on a polished round rod. This linear-bearing classification is often referred to as slides.

Purpose-built linear bearings are available for frequently encountered tasks, such as pull-out equipment drawers or storable work surfaces. These usually light-duty devices let polymer wheels or ball bearings ride on stamped or rolled steel rails. Telescoping arrangements allow designing pull-out equipment drawers into cantilevered positions while supporting up to 50 lb or more for maintenance.

Heavier loads are carried by linear guides that use re-circulating ball or roller bearings in rectangular mounting pads or slide units. These are so constructed that a loop of balls or cylindrical rollers cycles into and out of a load area along shafts at most any required load. Two, three, and four rails can work in unison to carry loads that exceed the rating of one rail.

The ball spline is a variation on this design. In it, the sliding unit is a cylinder with at least three and up to five circuits of re-circulating balls. There are dozens of cylindrical shapes to choose from. For instance, miniature designs are intended for instrumentation and pillow blocks are available when the rod must move while the rolling elements remain stationary. Some manufacturers boast of maintenance-free designs, which can mean several years between scheduled maintenance.

Long lengths can make use of a design in which the profile on a bearing-mounted wheel carries a V-shape that rides in a mating V on a rail edge. Such a design is less affected by debris and is said to operate without bellows and covers.

Nonlinear-linear bearings are also possible with permutations to the designs above. For example, so-called rectangular circuits have generously rounded corners, and oval rail circuits are possible by letting two sets of wheels or rollers ride in a groove on either side of the rail. Actuation can be provided by a timing belt mounted on the inside of the track.

Accessories for linear bearings include wipers that sweep a rail in front of a slide unit to keep dirt and debris from damaging rolling elements. Seals provide a similar function but are more intended to keep lubricant from seeping out of the bearing area.

A brief design checklist of considerations for a device requiring linear-motion bearings would include required rigidity, load, moment loads, and needed accuracy. Designers might also consider whether or not regular maintenance will be available, the possibility of vibration and how it could affect operations, and noise requirements. Of course, design is more complex than this. Manufacturers are likely to offer a range of shaft support shapes and materials, shaft material options such as particular carbon steels versus stainless, or even tubular shafts.

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The new Mid Rail Gantry Model MR513 water jet cutting machine is specifically designed for machine shops, fabricators as well as tile and stone shops. The Mid Rail Gantry is capable of cutting any complex parts from almost any material without developing a heat-affected zone (HAZ). It features one abrasive jet cutting head as standard. However, a second cutting head can be integrated to improve productivity. With optional mirroring, the Mid Rail Gantry can cut large portions twice as fast.

Featuring single or double carriages and direct-couple AC brushless digital servo motors, the company’s Mid Rail Gantry waterjet systems are offered in a wide array of work envelopes that range from 5′ x 5′ to 24′ x 13′. The Mid Rail Gantry water jets also use an industrial PC controller that can be configured in order that all three axes may be fully programmable (Z optional).

Powered by a waterjet intensifier pump from Jet Edge, the Mid Rail Gantry also features critical bearing components that are wrapped in heavy metal covers with brush seals. The Jet Edge currently has the largest portfolio of waterjet pumps on the market, with its offering ranging from 25 HP to 280 HP, including 60KSI (4100 bar), 90KSI (6200 bar) and 36KSI (2500 bar) models. The company also offers diesel and electric pumps.

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External roller bearings are fitted at the shaft’s motor end as well as at the discharge end’s hinged cover to provide optimum support and effectively eliminate vibration during heavy load operation. Opening the hinged cover causes the shaft to cantilever on the third roller bearing mounted externally between the material feed point and the motor-end bearing, permitting the internal parts to easily slide from the opposite shaft end.

Featuring Clean-In-Place (CIP) Spray Balls for quick sanitizing using cleaning solution or steam, the unit is made of stainless steel finished to 3-A, industrial, BISSC, FDA and other sanitary standards. The unit also features a stainless steel motor.

The Centri-Sifter centrifugal screener is specifically designed for food, pharmaceutical and dairy applications demanding thorough wash-down, and for general chemical applications that require frequent runs or screen changes/inspections of multiple materials without cross contamination.

Equipped with heavy-duty wedgewire screen, the horizontally-oriented cylindrical screening chamber is gravity-fed with moist or dry bulk solid material. A rotating helical paddle assembly speeds up the particle’s radial movement against the screen. This causes on-size particles to travel through the screen’s apertures and fall in a cone-shaped discharge chute, while the oversized particles are sent through the screen cylinder’s open end and thrown out through the discharge spout.

Aside from scalping and sifting dry bulk materials, the screener can also break up dewater moist slurries or solids and/or soft agglomerates.

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These cylindrical rolling bearings feature raceways oblique to the bearing axis, and can support high tilting moments as well as significant loads.

Featuring a conical bearing ring, the AXS bearings also have a roller and cage assembly that runs between the two hardened rings. They are currently offered from 8 mm to 175 mm bearing diameter. The AXS angular contact rolling bearing, usually feature a 45 degrees contact angle, 7 mm and 10 mm radial section heights and 1.2 mm bearing ring thickness. However, 60-degree contact angle bearings can also be utilized for higher axial forces as well as high tilting moments.

Meanwhile, SGL bearings are primarily set in “O” arrangements. The arrangement can, however, be easily adjusted to bearing preload from bearing clearance, depending on the requirements. The bearing cross-section, which is notably larger than the AXS bearings, offers higher axial and radial load carrying capacity.

Available in 8 mm to 200 mm bearing diameters, the SGL bearings normally have a contact angle of 45 degrees, depending on the application and load condition. Compared to conventional angular contact ball bearings, the SGL series can support significantly higher tilting rigidity. The bearings can be directly interchanged with series 718, as they correspond to dimension series 18.

The SGL bearings are suitable for applications that demand optimum rating life and tilting rigidity.

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GRAPHALLOY® 453 Bushings have proven to be successful in a variety of high temperature applications including bakery ovens, heat treat ovens, furnaces, conveyors, overhead paint lines, glass lehrs, louvers, dampers, valves as well as other environments where oil and grease cannot be used. Applications can experience improved performance through the use of GRAPHALLOY® materials.

Among their many advantages, GRAPHALLOY® bushings operate at longer intervals without the need for maintenance, which reduces costly downtime. They are an excellent choice for applications where service and maintenance tasks are cumbersome or difficult to perform. Additional benefits of GRAPHALLOY® include a low coefficient of friction and dimensional stability.

GRAPHALLOY® 453 bushings, like all GRAPHALLOY® products, do not soften at high temperatures or extrude under load. Installations of these bushings have operated for more than 10 years without maintenance. GRAPHALLOY® 453 Bushings are a proven solution for even the most challenging plant maintenance problems and new equipment designs.

Graphite Metallizing Corporation
www.graphalloy.com

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With one ring shoulder totally or partially removed, angular contact bearings ensure higher speed capabilities and greater load capacity by allowing larger ball complement than those found in comparable deep groove bearings.

The spindle bearings are assembled to a contact angle by altering the radial clearance and feature nominal contact angles of either 15º or 25º, which enables them to deliver improved radial rigidity and capacity.

The angular contact bearings are available in two variants — non-separable and separable.

In a separable bearing, the cage keeps the balls in place to separate the outer ring assembly, which holds the cage and the balls, from the inner ring.

Ideal for use in applications where bearings must be integrated in blind holes, the separable angular contact bearings are also used in applications where press fits are needed both in the housing and on the shaft.

The separable variant of angular contact bearings permit a dynamic balance between a rotating component and an inner ring mounted in place, and the housing and the outer ring.

Angular contact bearings support combinations of thrust and radial loading or thrusts loads alone. Angular contact bearings, however, do not accept radial loads only.

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To address such situations, GGB, formerly Glacier Garlock Bearings, developed a sealed bearing cartridge that gives off-road OEMs an alternative to conventional greased bronze, hardened steel and rolling-element bearings for demanding applications.

Savings come because the equipment does not have to be taken out of operation to be serviced. “The cost of a lubrication system is eliminated and maintenance costs are reduced,” said Charles Woods, global filament-wound products manager. “Plus, the equipment owner does not have to use a potentially environment-harmful lubricant or worry about spills.

Kansas State’s Advanced Manufacturing Institute developed this pin joint test rig (AMI photo).

The new sealed bearing cartridges are based on GAR-MAX™ filament-wound bearing material. Compared with a greased steel bearing, a sealed bearing cartridge can save about $525 over a five-year period, according to Woods. This reduction in cost of ownership is based on the elimination of grease labor ($187.50), bearing replacement and associated labor ($187.50), and downtime for bearing replacement ($150). For a piece of equipment containing 20 such bearings, for example, the savings over a five-year period would total $10,000.

The filament-wound bearings have a bearing surface of PTFE and high-strength fibers twisted together and encapsulated by a high-temperature epoxy resin enhanced with a self-lubricating additive. High-load capability is up to 90,000 lbs/in2. or 620 MPa. The bearings exhibit good tolerance to shock and edge loading, and because they do not absorb moisture and swell, they provide dimensional stability as well.

GGB worked with major off-highway OEMs and the Advanced Manufacturing Institute (AMI) at Kansas State University to prove that its sealed bearing cartridges outperform greased, hardened-steel bearings in several applications. The mission of AMI is to provide an array of resources to people and companies on advanced technologies. “We do this through collaborative engineering and business partnerships,” Taylor Jones, chief engineer, explains. “We use our engineering expertise to develop and transfer new technologies, as well as provide technical assistance to industry.”

“We had a client company looking for alternative solutions for pin joints in abusive applications,” noted Jones, “so the institute developed a test plan to evaluate current market offerings, such as greased hardened steel bushings, chrome-plated pins and different bearing materials. We contacted various suppliers, including GGB.”

GGB’s sealed bearing cartridges work in a wide variety of applications.

“One of the most common metal wear and maintenance problems for off-road equipment owners is pivot points,” continued Woods.

The test conditions simulated an abusive field application and heavy contamination by combining sand, dirt and water into a thick paste. “Most lab tests use a ‘mud box’ but the contaminant can wick away during oscillating and rotating test cycles,” explained Jones. “In our test, we wanted to simulate a machine that is constantly in and out of contamination all day long. We applied the paste right on the bearings.”

The tests also focused on conditions with bearing working pressures up to 7,500 psi, oscillating motion speeds that averaged 20 degrees/second and roughly 575 cycles per hour. A baseline test determined the duration of the GGB sealed bearing test.

The average wear of the sealed bearing cartridge was 0.003 in., as compared to an average wear of 0.022 in. for the traditional bushing, though the bearing cartridge was tested about 2.5 times longer than the greased hardened-steel bushing (600,000 cycles compared to 220,000 cycles).

“If properly sealed, the ungreased GGB sealed bearing cartridge appears to be a viable alternative to a sealed and greased hardened-steel bushing in severe work environments,” said Jones. “Any OEM using the sealed bearing cartridges in its equipment should follow GGB’s recommended design practices for a successful solution.”

An outer steel casing on the sealed bearing cartridges helps with installation and durability. Greasing is not required, resulting in an environmentally friendly product.

GGB LLC
www.GGBearings.com/sbc

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One Way Bearings are lightweight, compact, operate directly on a shaft and are ideal for transmitting high torque. The bearings are specifically designed to transmit torque between the housing and shaft in one direction while allowing free motion in the opposite direction.

One Way Bearings are offered both in a metric and inch series, with and without bearing assemblies. Those without bearing assemblies come in FC, HF and RC versions. The HFL series offers two integral radial bearings positioned on both sides of a needle roller clutch, allowing them to support radial forces in small or tight areas. Its bearing and clutch assembly can be utilized in a temperature ranging from -30°C to 120°C. Meanwhile, oil lubrication is recommended for a working environment above 70°C.

Boca Bearings also offers the EWC and the OWC One Way Bearing Series. The One Way Clutch bearings (OWC), which is also known as Origin One Way bearings are high performance bearings that are extra narrow. Allowing free overrun in the opposite direction, the bearings comprise of drawn cup roller clutch and cage and springs. Its CSK series are offered in two designs — the P-one keyway notch and the PP-two keyway notch series. The keyway enables the bearing to securely and perfectly fit into the shaft and provide the machine, appliance or conveyor belt extra torque.

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This new bearing comes with a unique design that delivers optimal performance, reliability and ease of installation, which translates to lower downtime attributed to maintenance intervals.

“The introduction of the ADAPT line underscores Timken’s long-standing commitment to the metals market,” remarked Mike Connors, Vice President, Distribution at Timken.

“We developed the ADAPT bearing in response to our customers’ requests for a caster application bearing that is easy to install, offers extended bearing life and improves performance. While caster applications are demanding on equipment components such as bearings, the innovative design of ADAPT provides durability and flexibility to keep casters operating at optimal levels.”

The new ADAPT bearing comprises a cylindrical inner ring, an outer ring designed with a proprietary outer race profile and a retainer/roller assembly that comes with a profiled rollers and a snap-in retainer. The bearing’s inner ring features a cylindrical raceway, which allows the shaft to float or move left to right relative to the outer ring.

Designed with a proprietary profile, the bearing’s roller and outer ring compensates for misalignment associated with shaft bending to a maximum of 0.5 degrees. It also enhances contact stress distribution for longer bearing life and develops a self-aligning effect with the rollers, which reduces skewing while keeping a constant bearing clearance.

The one-piece nitride steel retainer of the bearing snaps into position to keep the rollers in place during mounting and dismounting, while the outer and inner rings can be separately fitted for improved installation flexibility and easier handling. The component design of the ADAPT bearing simplifies removal and inspection while allowing operators to save time, costs and to independently change parts as required during maintenance.

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The company’s latest gage system features the most common form measurements, such as flatness, roundness, concentricity (in and out of plane), squareness and parallelism. For fast in-process shop floor TIR checks, a “live runout” feature has also been integrated. The gage system also offers an optional Wedge (or “Edge Thickness Variation” or ETV) measurement module, which can extend the analysis and automated measurement capabilities of the system for applications of the optics industry.

Featuring advanced technologies, the metrology platform of the gage system seamlessly blends maintenance-free, ultra-smooth rotary air bearing with a direct drive as the reference axis fitted in a cast iron base.

Through the innovative articulating gage arm design of the system, infinite flexibility in head orientation of the gage is now possible. Aside from providing unlimited positioning options for the gage stand, the system’s T-slot plate also allows users to utilize multiple stands.

ABTech’s MicroForm measurement software provides full function analysis for quality control labs and intuitive navigation for shop floor use. To assist novice operators, the system also offers on screen “step-by-step” instructions that do not affect the efficiency of experienced users. To meet the varying demands of users, the display and output options of the system can also be customized.

Using Ethernet network connections, users can easily save, convert to PDF, print, or export and share graphical charts and measurement results for traceability and statistical process control (SPC).

The gage system offers almost perfect linearity over the probe measurement range (correlation coefficient of 1) with a resolution of 0.1 µ”or 2.5 nm and overall system accuracy of below 5.0 micro-inches or 0.125 micron.

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These tin based babbit materials are also suitable for high temperature bearing applications up to 175°C (350°F) and can perform well as self-lubricating bearings in dry and submerged applications.

GRAPHALLOY, which is a graphite or metal alloy, provides various advantages. It effectively eliminates the need for oil or grease and is environmentally safe to use and machine. The elimination of liquid lubricants reduces maintenance and contamination.

Offering superior heat dissipation without melting or cold flow, GRAPHALLOY Tin Based Babbitt materials can also be used as a substitute for plastic. In low temperature applications, such as -400° F/-205° C, these new bearings of Graphite Metallizing Corporation solve lubrication issues caused the viscosity to oil and grease that commonly prevents proper operation of equipment.

The all-new GRAPHALLOY Tin Based Babbitt offers all the necessary performance benefits of traditional babbit materials. Users need not worry of any environmental concerns since it can be safely used in food applications, drinking water applications and traditional low temperature applications. For new equipment design and the most challenging plant maintenance, GRAPHALLOY bushings and bearings provide the proven solution.

Aside from being self-lubricating, GRAPHALLOY materials are also impervious to extreme temperatures (from -400°F to +1000°F/-240°C to 535°C). Used in the manufacture of bearings, bushings and other for process and machinery equipment, GRAPHALLOY materials thrive in the most extreme environments where other competing bearings fail.

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With the evolution of RC engines, they now come under greater thrusts loads than before and are using more nitro fuel. The nitro fuel quickly dries the thin stock bearing retainer, making the whole bearing vulnerable to premature failure when subjected to heavy radial and thrust loads. With the introduction of the expanded portfolio of MX Bearing, this particular issue will no longer be a problem.

The company’s MX bearings offers a new and unique internal design that increases load capabilities and enables the bearings to function even under extreme operations, where shafts are exposed to excessive radial and side load.

The MX bearings come in both as a ceramic hybrid, with chrome races and ceramic balls, or as a standard high-speed version featuring chrome steel balls or races. The races are cryogenically processed to achieve a harder surface, while the chrome steel is utilized since it is harder than stainless steel. To enable the bearings to withstand high nitro content fuel, the company used a thicker and stronger retainer material for this new portfolio. Moreover, Grade 10 balls have also been used to provide a closer tolerance to optimized performance.

Aimed at engines with known stock bearing issues, the new line of MX Bearing is currently offered in a limited size range. The company has specifically developed the MX Engine bearings to deliver extended life and increased speed to RC engines.

Meanwhile, Boca Bearing offers an additional discount on all MX Engine Bearings kit. Complete bearing kit is now available for engines such as OS, Sirio, and Picco.

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Specifically designed to match eccentric shaft bearings within refrigeration compressors, the new FAG axial ball bearings replaces the plain bearings that are usually utilized in these mounting positions.

The company offers a selection of four kinds of FAG axial bearings which customers can freely combine. Its bearing cages come in either sheet plastic or steel, matched to the current operating environment. Both of its bearing washers can be supplied with or even without raceways. The materials of the axial bearings are resistant to varying temperatures and offer excellent compatibility with coolants.

FAG axial bearings’ sheet steel cage features a unique “filigree” or a twisted wire design provides high rigidity, making it more ideal than plastic cages for the bearing’s high temperatures. Moreover, it eliminates the need for coolant compatibility tests.

The axial washers’ raceways improve ball rotation and load distribution as well as provide secure guidance for the ball. Aside from a reduced wear, these remarkable characteristics also result in a longer operating life. To provide more mounting security, the company also offers bearings that feature raceways on both sides.

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“By eliminating the need for ball bearings, these food grade bushing bearings can operate on soft shafting such as Thomson ‘corrosion proof’ 316 Stainless Steel or Ultra Light Aluminum LinearRace shafting to deliver exceptionally long life and reliable operation in washdown environments,” said Tom Dwyer, Business Unit Manager at Thomson Linear Bearings & Guides.

The bearings have been specially designed to offer robust liner material that can handle heavy loads with a maximum static pressure value of up to 1000 psi, support a maximum continuous PV value of 10,000 psi ft/min and deliver maximum no load speeds to 400 ft/min. in temperatures between -400°F up to 385°F. The bearings can be combined with a vast array of corrosion resistant LinearRace shafting options, including Ultra Light aluminum and plated 60 Case, 440C and 316 Stainless Steel, in order to optimize performance suited to the application’s requirements.

“Stainless Steel pillow block assemblies are a particularly significant option in food processing applications, as carbon steel will corrode over time, and even aluminum is susceptible to corrosion caused by the caustic solutions commonly used in washdown environments,” added Dwyer.

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Ceramic materials that are generally used for bearings are Zirconia Oxide (ZrO2), Silicon Nitride (Si3N4), Silicon Carbide (SiC) or Alumina Oxide (Al2O3). The non-porous, glass like surface of ceramic can be used in clean rooms where traditional emissions and lubrications cannot be present. Ceramic is also non-corrosive, non-magnetic and has a very low rate of thermal expansion. Thus, ceramic bearings can be utilized in producing silicon wafer where high temperatures and high loads are exhibited during production.

Full Ceramic and Ceramic Hybrid versions offer various bearing styles, which include deep groove bearings, angular contact bearings, thrust bearings and self-aligning bearings. Ceramic Hybrid bearings feature steel races with ceramic balls, while Full Ceramic bearings have ceramic balls and ceramic races. The company offers the world’s most extensive inventories of ceramic bearings. It also provides custom built bearings to cater to the needs of the customer.

One of the world’s trusted company in ceramic bearings technology, the Boca Bearing Company’s hallmark since 1987 is the conservation of energy and the reduction of rolling resistance. A one stop shop for prototyping to production, the company requires no minimum order. The company’s broad portfolio of bearings meets the needs of customers, whether they are looking for high speed, longevity or affordability. Boca Bearings also offers wholesale discounts.

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Christian Klatt, Cerobear’s Vice President of Sales, announced the 20 years milestone of the company in hybrid bearing and ceramic production, for chemical processing factories worldwide.

Klatt said the company is very proud of marking 20 years of continuous service to the chemical sector. Since the early 1990s, the company has worked hard to meet and exceed customers’ demand of receiving reliable hybrid bearings at affordable costs but with longer operating cycles and proactive technical support, he added.

Cerobear’s proprietary manufacturing, high quality products, materials expertise and intense focus on bearing’s long-term reliability have earned the company a reputation for excellence.

The company’s advanced hybrid bearings and ceramic are available in roller and ball types. These bearings are highly sought by engineers in the entire chemical industry because they perform continuously and seamlessly – even without or with little lubrication only – in the most adverse and demanding operating conditions.

“For extreme chemical bearing applications such as LDPE and EVA autoclave reactors, we can offer a service life of approximately five to six times the service life of conventional bearings,” said Klatt. “This is the result of Cerobear’s total commitment to improving bearing reliability, offering advanced bearing designs and our superb production quality with the proactive guidance of our bearing engineers.”

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The iglide A350 delivers low coefficients of friction and is resistant to a variety of chemicals and other liquid media. The plain bearing is also corrosion-resistant, lubrication- and maintenance-free. The iglide plastic plain bearings are available in more than 7,000 sizes and styles from stock.

For more information, e-mail sales@igus.com or visit www.igus.com.

www.igus.com

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Electro Static Technology’s kit features the AEGIS mounting hardware and grounding ring for most motor designs. The kit is ordered based on the NEMA “u” shaft diameter and depending on the shape of the motor’s end bracket, it provides the correct size ring for the motor and four styles of lock washers and brackets with bolts, which can be used in configurations.

Useful for motor repair shops, HVAC service contractors, original equipment manufacturers and plant maintenance departments, the ring prevents electrical “fluting” damage in the bearing, expensive motor repairs or replacements, bearing noise and downtime by safely directing VFD-induced bearing currents to ground. To make installation of the ring on NEMA frame motors easy, the brackets in the U-Kit can be mounted on the motor either by using AEGIS Conductive Epoxy or by drilling and tapping small holes.

The ring’s conductive microfibers are integrated securely in the AEGIS FiberLock channel and surrounding completely the motor shaft to provide discharge points to dangerous shaft currents. The design creates the path of minimal resistance, which redirects these currents effectively away from bearings to ground. The microfibers are designed for flexibility to prevent breakage.

AEGIS
www.est-aegis.com

Motion Control Tips

The evaluated information forms the basis for repair and maintenance actions and is critical for railway supervisory systems, including online timetable generation, localization, risk and process analysis, routing and others.

The Train Support System is a recipient of the Intelligence for Transportation and Logistics innovation award from the Center for Transportation & Logistics Neuer Adler e.V (CNA) in Germany.

The company’s axlebox bearing was used with an integrated GSB as the self-sustaining source of energy in rail freight wagons. Schaeffler designed the software and system electronics and incorporated them in the GSB to form an onboard unit.

Just like a dynamo, the GSB induces the needed electric power through the rotating movement of permanent magnets situated on the wheel axle. The power is usually around 100W at a nominal voltage of 24V. Hence, an independent, self-sustaining energy source is at hand, which offers additional functions via an electric storage unit, such as the detection of sensors and switches or the automatic opening of doors.

For the Train Support System, the company has upgraded the GSB with an advanced electronic system into an onboard unit and connected it with a higher-level information management system, enabling not only the processing and recording of signals in the bearing, but also the transmission of data via GPS satellite technology.

Motion Control Tips

The Timken 454-Series of bearings features a special design to accommodate the 2″ offset loads incorporated in many new axle designs. Its surface finishes and highly engineered raceway profiles deliver optimal performance. Together with the new Set-Right Hub Rebuild Kits, the 454-Series bearing technology enables easy maintenance of consistency in the fleets’ installation procedures for preset wheel ends.

With the introduction of the 454-Series Set-Right Hub Rebuild Kit, MileMate matched sets and traditional Set-Right Kits, Timken offers complete bearing options to serve all wheel-end configurations, including preset varieties and wide-singles. Latest testing reveals that Timken’s tapered roller bearings offer seven times the bearing life of their closest rival in heavy-duty applications.

The performance and engineering of Timken’s heavy-duty wheel end bearings has propelled them to be the choice of commercial vehicle manufacturers. A range of product options, combined with consistent technical support and training, strengthened Timken’s leadership in the aftermarket and original-equipment sectors.

With the growing demand, Timken observed that it has been strengthening capacity at facilities that are vital to its heavy-duty supply chain and with other industries. Last year, it announced a $50-million investment in its US-based steel making capacity, and earmarked a $1.7-million investment for its Lincolnton, N.C. bearing plant this year.

Motion Control Tips

Among the new Ball Bearing products introduced in MISUMI’s 2011 Metric Catalog of Mechanical Components are:

• Deep Groove, Double Shielded – Economy Type
• Deep Groove with Flange – Multiple new specs have been added.
• Deep Groove, Single Shielded
• Deep Groove, Double Shielded with C3 Clearance – Radial clearance is larger than standard products. Especially well-suited for tight joining fit and potential temperature difference between outer and inner rings.
• Deep Groove, Contact Sealed, Stainless Steel – Made of 440C SS with NBR (nitrile rubber) seal. Offers better moisture and dust resistance than standard open, double shielded and non-contact sealed styles.
• Deep Groove, Small, Double Shielded – Economy Type. Multiple new Contact Sealed styles have been added to Non-Contact Sealed styles.
• Deep Groove, Small, Open
• One-Way Clutches – Feature bearings at both ends of the clutch to support radial loads. Clutch locks in one direction and free spins in the other direction.
• Self-Aligning Ball Bearings – Self-alignment feature enables the ability to tolerate mounting misalignment and deflection during rotation. Suitable for use in drive shafts which tend to deflect, or where precise alignment of shaft and housing are difficult.
• Deep Groove with Groove – Three different styles in 440C Stainless Steel: V-Groove, SZU U-Groove, and SZG G-Groove.

MISUMI USA, Inc.
http://us.misumi-ec.com

Motion Control Tips

The bearings are designed to minimize the overall ownership cost and are factory assembled, lubricated and sealed.

The replaceable inner unit allows another factory assembled, lubricated and sealed unit to be integrated without being subjected to environmental contamination.

DODGE’s hydraulically mounted bearings are offered in sizes from 150 mm to 400 mm.

With the launch of the new range of bearings, easy mount/dismount bearings from Baldor is available from 17 mm to 400 mm in three separate lines of bearings, which include the ISN, the Hydraulic ISAF and the Grip Tight range.

Environment contamination is a main cause of bearing failure, which can occur either in service or during installation particularly under misalignment conditions.

The DODGE Hydraulic ISAF bearings offer a double seal that is useful even under misalignment conditions. The inner unit features a triple lip seal and its housing has optional closed end cover or a grease purged labyrinth design.

The multiple seal design eliminates the risk of environment contamination, allowing the bearings to reach its maximum life.

Daniel Vera, managing director of Baldor, said: “The new Hydraulic ISAF bearings eliminate a wide range of issues faced by customers in terms of installation, maintenance and removal of mounted bearings, especially in contaminated environments that can further impact the life-span.”

Motion Control Tips

Tube roller bearing is a conventional cylindrical roller bearing that is used at a specific running condition. It has been adapted so that three rollers are larger in diameter than the normal and are made as hollow tube rollers.

The purpose of this feature is to enable the bearing to withstand a wide range of loads.

It only uses three hollow rollers when the loading is low to keep the rolling elements rotating through a slight preload in the contact surfaces. The hollow rollers will flex slightly without surpassing the steel’s elastic limit when the load suddenly becomes heavy.

”Underloading a bearing can be just as damaging as overloading because, when the load is not heavy enough, the rollers slide or skid instead of turn. The hollow roller bearing is particularly suited to steel mill applications, where the load varies substantially,” said Eugene Nortje, field service engineer of Schaeffler South Africa.

The ball roller bearing is almost the same to the average ball bearing; the only difference is that 15 percent of the ball rollers’ side has been ground down, which results in a ball bearing that is 30 percent narrower than the average.

”The recession spurred this movement as plant owners tried to save money by maintaining their plant instead of buying new bearings, and lubrication plays a key role in bearing maintenance,” added Nortje.

Motion Control Tips

Schmidt Offset couplings provide the utmost in precision for parallel offset shafts. They transmit constant angular velocity and torque in a wide range of parallel shaft misalignments. With a time-proven design, they are used in a wide range of machine applications such as printing, embossing, paper converting, pharmaceutical, and automated assembly systems.

The new Schmidt sealed bearing coupling feature incorporates needle bearings with internal micro-poly lubrication. There are no lube fittings making for a cleaner coupling setup.

Compact in design, Schmidt Offset couplings with the new zero maintenance bearing option keep out contaminants and foreign matter, enabling the couplings to be used in less than ideal operating environments.

Schmidt Offset couplings are designed to handle high amounts of parallel offset up to 17 inches and are available with torque capacities up to 459,000 in-lbs. They impose no side loads on shafts or bearings and eliminate radial shaft vibrations.

Zero-Max
www.zero-max.com

Motion Control Tips

ETP bushings incorporate a double walled sleeve encapsulating a pressure medium. When the actuation screw is tightened it forces the inner and outer wall of the bushing to expand uniformly against the shaft and hub of the mounted component. The result is concentricity to .001” T.I.R. Mechanical devices, by comparison, rely on precise and accurate tightening of the actuation screws to avoid excessive T.I.R. Additionally, extremely high compressive forces are imparted on the shaft by mechanical bushings.

ETP bushings are ideal where repeated mounting and dismantling of components is required. ETP Bushings are consistently accurate and easy to use.

The ETP Classic has flange mounted actuation screws. The ETP Express has just one mounting screw positioned in a radial location. The single actuation screw of the ETP Express is the fastest and easiest way to mount components accurately. The single actuation screw saves space, time and is easy to access.

Both ETP Classic and ETP Express operate in temperature ranges from -22° to 180° F. The ETP Classic handles torque ranges from 40 to 11,413 ft lbs while the ETP Express handles torque ranges from 40 to 6,400 ft lbs. Both require no lubrication. They are available in a full range of inch and metric sizes in both standard steel and stainless steel.

Zero-Max
www.zero-max.com

Motion Control Tips

Easy to install, versatile combination options

Bearing manufacturer NKE presents its range of ready-to-mount bearing units. The bearing units that consist of a bearing fitted in a cast or pressed housing, offer simple, reliable and cost-effective bearing solutions for material handling systems like conveyors. They are also used in heavy and agricultural machinery as well as the steel industry.

The housings of the bearing units are made from cast iron or pressed sheet steel and can be combined with a range of different bearing inserts. Having a high stiffness, cast iron housings are resistant against deformation and can therefore absorb moderate to high loads. For applications with lower loads, galvanized pressed sheet steel housings are available. These have a much lower weight than their cast counterparts and are easy to install.

The bearing inserts consist of single-row deep groove ball bearings that are sealed on both sides against moisture, splash water and dust. Various seal types are available for different applications. The bearings are secured to the shaft with set screws or eccentric locking collars, which simplifies their installation. The bearings are factory lubricated and most bearing-housing combinations can be relubricated during operation to extend service life. The special version SQ171 is coated for corrosion protection.

Through the spherical design of the bearing’s outer diameters and the housing’s inner diameter, the units are self-aligning. This lets any misalignments that occur during installation or operation are compensated. NKE’s bearing units are interchangeable.

NKE produces standard and special bearings for all industrial applications. In addition to product development and application engineering, NKE provides a full range of technical services and training. NKE’s products are distributed through 15 international representative offices and more than 240 distribution outlets in 60 countries.

Motion Control Tips

As newer motion equipment demands more in terms of precision, the crossed roller bearing has gained prominence for use in friction reducing devices. Here’s a closer look at its features and suitability for your motion system design.

Rollers in a resin cage can be closer together. Cage creep can be prevented by studs that roll into the raceways depressions.

Linear bearings have evolved rapidly to carry heavier loads, take up less space, and deliver precise positioning reliably. In cancer research, for example, to find one cancer cell on a slide holding a billion cells, the microscope depends on sample positioning, bringing the images into focus and moving the proper filters into place to produce an image in three colors. The automated movements within the instrument work in concert with one another to take multicolored images of the cellular sample that is in the chamber. The linear bearings have to meet specific requirements to achieve perfect positioning. These are determined by the amount of space within the product envelope, distance to be traveled, load to be carried, and most critical of all, the degree of accuracy needed.

When referring to linear bearings, the reference usually is to devices that incorporate ball bearings – meaning friction is reduced between moving parts by recirculating (usually metal) balls. Bushings, ball splines, linear guides and slides typically incorporate recirculating ball bearings.

Resin retainer fits around the roller so the whole shape can be in contact with the load

As newer motion equipment demands more in terms of precision, another type of bearing has gained prominence in friction reducing devices – the crossed roller bearing. High-tech microscopes, wafer manufacturing equipment, robots and vision inspection systems increasingly rely on crossed roller bearings.

Crossed-roller slideways or bearings are the most accurate form of mechanical linear motion component. Also known as crossed roller slides, these bearings work similarly to ball bearing slides, except that those housed within the carriage are cylinder-shaped instead of ball shaped. The rollers crisscross each other at a 90° angle and move between the two parallel guides (alternately termed table and bed) that surround the rollers. The rollers are between “V” grooved bearing ways or raceways ground out of the guides. The travel of the moving guide/table, ends when it meets an end cap, a limiting component.

Crossed roller slides offer a line of contact, versus a ball bearing’s point contact. The line of contact creates a broader contact surface that can carry a heavier load. Such a feature offers more rigidity, less deformation, and thus more accuracy compared to the point contact of balls. Plus, due to the crossed rollers’ consistency of contact between the carriage and the base, erosion is slower. The recirculation of ball bearings creates vibration when the balls leave the load-carrying path to recirculate. Because most crossed roller bearings do not have recirculating components, this source of vibration is eliminated.

Load capacity: resin versus metal cages
Roller-to-rail contact determines load capacity. Of course, rollers provide a large contact area, since they usually do not recirculate they are all carrying the load, which produces greater rigidity as well as high load capacity. Balls typically contact at a single point, though a raceway’s surfaces can be designed as curves to increase the points of contact.

There is a direct correlation between the contact area of the crossed rollers and load capacity. Load capacity can be increased as much as 250% by designs with greater roller-to-rail contact. The closer together the rollers are, the more rollers can be fitted into the same space and the more weight per inch the linear device can carry.

How the cage holds the rollers also governs the amount of roller contact area per inch. Since the amount of space between the rollers is a factor in calculating the roller surface per inch available to carry a load, the design of the cage surrounding the rollers is important.

Traditional metal cages limit, some-what, the rollers’ contact area because of the way the cage holds in the rollers. However, the more recent development of resin retainers offers more design options. Resin retainers/cages can be shaped to allow a larger contact area with less space between rollers. They can also be thinner in critical parts.

Metal and resin cages hold the rollers in different ways. Metal cages hold the rollers through a notch on the top and on the bottom of the rollers. However, the resin retainer fits around the roller. The resin retainer is able to harvest the whole shape to be held. The whole shape can be in contact with the load because the resin retainer exposes the necessary contact areas. It doesn’t compromise the contact area when holding the rollers.

Rollers in a resin cage can be closer together. This increases the number of allowable rollers within the cage length. So either the cage can be shorter while maintaining the same load capacity, or while maintaining the same cage length the load capacity will increase with the increase in the number of rollers per cage. A resin cage can afford at least a 30 to 58% increase of the contact area as compared to a metal cage.

Metal cages are less expensive and can be all stainless or steel. Therefore they can be used in high temperature or medical applications involving water. Metal is also better suited in a vacuum since resin can have out-gas emissions.

Deeper V-grooves allow greater roller contact.

Travel length
The longer the travel the longer the rail has to be. However, as opposed to recirculating-ball bushings, which require a shaft only as long as the travel distance, with crossed roller bearings, the whole rail assembly must be twice as long as the stroke. That’s because both rails containing crossed roller bearings move in opposite directions. So the whole assembly has to move within a space that is twice as long as the travel length. (The exceptions are in the minority of cases in which crossed roller linear guide products have recirculating crossed rollers or roller guide products that are not crisscrossed – having four circulations with opposite roller orientations. These products don’t need rails moving in opposite directions.)

With a resin cage, stroke length on a given length rail can be longer because the cage can be shorter for a given load.

Travel limits
The length of travel is limited by the space available for the rails within an application. Since the rails move in opposition to each other, the space required is twice the distance that the load will be carried. An endstop limits travel length. Because there is little or no difference between static and dynamic frictional resistances – even under low-load conditions – crossed roller bearings are well suited for minute motion.

Wear
For motion control applications with extremely fast acceleration and deceleration (at dimensions ranging from 30-600 mm lengths, 2-12 mm rollers) endurance can be 150 million cycles.

In crossed roller bearings without anti-cage creep mechanisms, cage creep may necessitate the replacement of guides and readjustment of the machine or installation. This affect often occurs as a result of high acceleration and uneven preloading or load distribution, as well as orientation (inclined or vertical) can easily cause creep.

Smoothness
A benefit of not recirculating is less frictional resistance fluctuation making them extre-mely quiet and smooth. Crossed roller bearings are almost as quiet as cage-limited non-recirculating linear bearings using balls.

Accuracy and deflection
Crossed rollers provide a large contact area, which reduces elastic deformation. Because of this greater stiffness, crossed rollers provide consistently precise movement.

The crossed roller is less forgiving of mounting surface inaccuracies because of the linear bearing’s rigidity and the way they are designed. They’re much less forgiving of an inaccurate mounting surface than recirculating ball bearings. For recirculating ball bearings precision, 5 – 10 microns of deflection is accommodated.

Because crossed roller bearings are so precise, they must have a very accurate mounting surface to fully ensure their acc-uracy. Often the bearings can be specified with mounting tables hone to exacting standards. This makes sense since for ultra precision, 2 microns is the maximum allowable deflection from the mounting surface.

Fit and interchangeability
The cage in any bearing prevents ball-to-ball or roller-to-roller contact, which can cause more friction and wear. Whether the cage holding crossed roller bearings are metal, resin or other material, it alters, somewhat, a crossed roller bearing’s dimensions, which affects how they fit into a design. Stoppers can also affect their size and therefore their fit.

Resin, as opposed to metal cages, allow the crossed rollers to be much closer together allowing the total number of rollers to be greater in the same space. Also, because of the additional contact area allowed by a resin cage, load capacity will be high, as well. In any case, it is prudent to contact the manufacturer and provide them with the required stroke length to accurately determine rail and cage lengths before ordering.

In addition to stoppers and the cage material and design, another factor that affects interchangeability is the design of the anti-creep mechanism. External anti-creep mechanisms often obviate interchangeability. Internal mechanisms are much more accommodating.

Cage creep
In non-recirculating linear components, the retainer floats between the rails and can drift (or creep) from center position. As the roller cage creeps away from center, it will begin to restrict the slide’s travel. It will creep over time if a full stroke is not used, especially when mounted vertically. If, after the retainer drifts, the full stroke is once again used, the retainer will hit the endstop of the rail and be forced to skid in order to center itself again. This action requires a strong motor and can damage the retainer, the rollers and the slideway. With higher preload, it is even more difficult and damaging to skid the cage back in place. Cage creep is damaging because every time it creeps, rolling ele-ments are not rolling, instead they are slipping and causing metal to metal rubbing, which will wear out elements very quickly.

Metal cages hold the rollers through a notch on the top and on the bottom of the rollers.

Anti-Cage creep mechanisms
The term “anti-creep” describes the method used to eliminate any slippage of the retainer holding the crossed rollers between the two V-grooved rails of the slideway.

By eliminating ‘creeping’ of the retainer, the slideway can be used in any mounting direction and with lower momentum motors, such as linear motors. Several complex anti-creep devices have been developed and manufacturers have used a few different approaches, such as a rack and pinion mechanism; an external attachment made of plastic gears outside of the rail; and a metal gear inside of the rail. Some of these devices are quite expensive.

There is one mechanism that does not use a gear. It is an anti-cage creep mechanism that uses a roller with round balls studded around its surface. It has the smoothest tracking motion and therefore is quieter than an externally attached toothed-gear type anti-creep device. This Studroller™ mechanism, prevents creepage because the raceway has depressions that track the studs or nodules, preventing slippage – in any position.

By placing studs in the center roller and machining a path along the rail, this retainer will never slip. It is suitable for high acceleration, vertical mounting and uneven load distribution. The Studroller™, is a simple non-slip design and uses a ball bearing as opposed to a gear or exterior control, so its cost is almost the same as a standard slideway; plus, there are no re-design costs to replace a standard slideway.

Discuss this on The Engineering Exchange:

NB Corporation of America
www.nbcorporation.com

::Design World::

Motion Control Tips

Among the highlights is a new 8mm series of sealed metric REALI-SLIM® bearings that gives designers more versatility. The series adds 28 new part numbers, with bore sizes ranging from 25mm to 170mm, to the Type C (radial contact) and Type X (four-point contact) bearings,

Kaydon has expanded its JG series of sealed REALI-SLIM® bearings, adding 12 new part numbers with bore sizes as small as 7.0 inches. The JG series now spans a range from 7.0 inches to 40.0 inches. Also expanded is the number of bearings in the catalog available from stock.

In addition to the new offerings, the catalog features more user-friendly features, including an expanded index and common English-metric equivalents. It retains popular features, such as sizing charts, deflection and load graphs, and an application worksheet to request a free, customized application engineering review.

Kaydon Corporation
www.kaydonbearings.com

Motion Control Tips

The new hybrid bearing, DryLin® WJRM, was developed with the goal of reducing driving force, especially in applications involving the manual adjustment of machine-guard doors, partitions and adjustable locks, or for light handling tasks. For this purpose, igus took the advantages unique to sliding and rolling movements and combined them.

A self-lubricating plastic, sliding sleeve bearing ensures the hybrid linear system is robust, dirt and moisture resistant, lightweight and low cost. Meanwhile, a maintenance-free polymer roller brings ease of use to applications where heavy machine doors up to 110 pounds have to be adjusted manually. The required driving force is reduced by a factor of 4 to 5 due to this roller bearing, which carries the main load. This makes manual operation much easier.

The new hybrid bearing is the latest extension to the tried-and-trusted DryLin W linear guide range from igus. The extremely compact system was modeled by igus’ design engineers in such a way that the rollers fit inside the linear profile without increasing height, which remains at a low profile 0.71 inches (18 mm). Standard linear guide profiles can be used, which are available in three styles for shaft diameters of 0.39 (10 mm): as individual rails for more flexibility and as double rails for fast installation without time-consuming alignment. The latter comes with a distance between rails of 1.57 inches (40 mm) or 3.15 inches (80 mm). The hybrid bearing housing is made from blue-chromed die-cast zinc.

DryLin W is a flexible, modular linear guide system made from hard-anodized aluminum profiles, die-cast zinc housings, stainless steel or aluminum and plastic plain bearing materials. The wide variety of different combinations within this easy-to-install system allows users to optimize available design space. DryLin W linear guides work without lubrication as dry-running systems and do not require maintenance during operation. They use plastic liners made from iglide® J or iglide J200, both of which are extremely low wear and have a very low coefficient of friction. They are also chemical resistant, vibration dampening and absorb negligible amounts of moisture.

igus
www.igus.com

Motion Control Tips

NKE double row full complement cylindrical roller bearings with maximum load carrying capacity

The maximum radial load carrying capacity of the NNF series cylindrical roller bearings is accomplished through the full complement design, i.e. a maximum number of rollers is fitted within the available cross-section. They are suitable for low to medium speeds and can take up axial forces and tilting moments in both directions. To prevent dust and splash water from entering the bearings, the NNF series is equipped with contacting seals on both sides. A special grease allows the bearings to operate under extreme conditions. Lubrication holes in the outer and inner ring enable easy re-lubrication through shaft and housing.

An application example for double row full complement cylindrical roller bearings: Cable sheave for lifting blocks by Dutch company De Haan Special Equipment B.V.

Rope wheels and pulleys are typical application examples for NNF series double row full complement cylindrical roller bearings. Due to the narrower outer ring, additional sleeves or distance pieces are not required. Two snap ring grooves on the outer ring simplify the bearing arrangement design for sheaves. For better corrosion protection, the bearings are also available with a special, RoHS compliant anti-corrosion coating SQ171. Black oxide coating can also be realised to optimise the tribological characteristics of the bearings. Furthermore, the bearings can be manufactured in application specific clearance and tolerance classes.

NKE AUSTRIA
www.nke.at

Motion Control Tips

Quotes and online orders are available at the new QBC eStore, where users can check price and availability, place an order or request a quote. QBC also provides custom-made bearings and shafting as well as on-site relubing of bearings in a certified class 1000 clean room.   

Detailed technical specifications are available in catalog B620, available free from the company. The catalog can be viewed in PDF format and downloaded by section at the QBC web site www.qbcbearings.com, or via mail request at: 125 Railroad Avenue, Garden City Park, NY 11040-5016

Phone: 1-888-276-4787, fax: 516-616-0443

www.qbcbearings.com/Press/PlasticBearings.htm

Motion Control Tips

These bearings are 80% lighter than conventional steel spherical bearings. They can withstand aggressive cleaning agents because they are corrosion and chemical resistant. They also do not require grease, which could contaminate the products being packaged.

igus
www.igus.com

Motion Control Tips

These quiet, low-cost bearings can be a superior alternative to traditional linear bearings in many applications. Chemically resistant, plain bearings thrive in high load, harsh environments, high speed linear/rotary, rapid oscillation, high impact, and shock. They are FDA/USDA compliant, and can be washed down with water, high-pressure steam, strong disinfectants, and caustic foaming agents, and they are approved for direct food contact. These bearings are ideal for use in: Food processing and packaging, medical products, and pharmaceuticals manufacturing, robotics, assembly equipment, construction equipment, and marine applications.

LM76 also provides RC 60, 300 series stainless steel, and ceramic-coated shafting, as well as pillow blocks and flange blocks in aluminum, ceramic-coated aluminum, and stainless steel. Additionally, custom blended polymer bearings can be ordered for extreme applications such as high heat.

The self-lubricating Minuteman Series bearings are drop-in replacements for traditional linear ball bearings. They are available in inch sizes up to 4.00 in., are lightweight, chemically inert, and ideal for highly contaminated environments experienced by construction machinery.

The LM76 Ceramic Coated Series of plain bearings easily handles high-speed applications and loads up to 10X that of linear ball bushing bearings.

The FDA/USDA compliant plain bearings from LM76 include Washdown Rated self-lubricating PTFE bearings in 304 stainless steel shells in diameters from ¼ in. to 1.5 in., FluidLine Linear Motion Bearings^TM, are self lubricating, low friction, lightweight plain bearings that are designed for applications requiring FDA/USDA and 3A compliance.

The LFG Series of plain bearings features a glass epoxy shell and Minuteman polymer liners for high load, high impact, high shock, and high vibration applications.

Phone: 413-525-4166, Fax: 413-525-3735

www.lm76.com

Motion Control Tips

Developed with vacuum lubrication and materials and thin-film technologies for space exploration equipment, the SPACEA series of technology-driven products incorporates unique coatings and materials, including ceramic, anti-corrosion and solid lubricant, to meet the strict requirements for harsh operating conditions and clean room environments. The series offers extended product life over conventional NSK bearings, ball screws and linear guides, as well as high functionality, maximum performance and outstanding quality.

NSK will demonstrate the SPACEA series in booth 5971 at Semicon West 2009.

NSK Precision America
www.nskprecision.com

Motion Control Tips

QBC has in stock: miniature bearings, plastic bearings, rod end bearings, spherical bearings, pillow blocks, sintered bronze bushings, radial ball bearings, thrust bearings & washers, sleeve bearings, needle bearings, inner races, roller clutches, guide wheels & rail systems, linear ball bearings, inner and outer ring spacers and shafting. QBC stocks both inch and metric sizes. Our eStore allows you to check price and availability, place an order or request a quote anytime. QBC also provides custom-made bearings and shafting to the customer print. We also offer on-site relubing of bearings in a certified class 1000 clean room.

Quality Bearings & Components
www.qbcbearings.com

Motion Control Tips

These features allow for greater travel, up to 38 degrees of total misalignment, vs. “conventional” bearings which usually offer about 12 degrees of misalignment. Typically found on racecar and related applications, they are an excellent choice for extreme situations and environments in all industries.

The Aurora HXAM series rod ends and HAB series spherical bearings are constructed of premium materials, and feature Aurora’s exclusive AT 3200 PTFE liner, qualified to AS81820. The HXAM series is an oversize shank style part, with the shank or thread being larger than the ball bore.

www.aurorabearing.com

Motion Control Tips

They are designed to fill the gap where conventional ball bearing performance is limited by parameters such as temperature, chemical or moisture exposure. Special solutions are generally difficult to come by or only available at great cost, so igus decided to apply its years of experience working with tribologically optimized polymers to replace ineffective standard materials.

The races and cage of the new ball bearings are made from igus’ high-temperature material iglide® A500, which has an exceptionally good chemical resistance. The corrosion-free balls are made from stainless steel, although glass balls are available for maximum corrosion resistance. The deep-groove ball bearings are available for varying shaft diameters and are temperature-resistant up to 302 degrees Fahrenheit. Application areas for these bearings include medical engineering, chemical, food, pharmaceutical, biotechnology and plant engineering.

According to igus, the dry running polymer ball bearings do not compare with permanently-lubricated metal roller bearings when it comes to service life, speed or permissible loads. However, in many applications this is not an important factor; instead, low friction values and minimal driving forces are usually the basic requirement.

The igus polymer ball bearings are unique because they are available from stock and can be used in combination with potentially corrosive elements, such as chemicals. They do not require any lubrication, making them compliant with food industry standards.

igus intends to expand this range in keeping with its ongoing pursuit towards customer-specific solutions using high-performance polymers.

www.igus.com

Motion Control Tips

The gearbox of SeaGen is equipped with nine types of NKE bearings.

Tidal current turbines are among the latest developments in renewable energy. Installed undersea, the turbines are driven by the tidal flow of water. Bearing manufacturer NKE Austria supplies the bearings for the gearboxes of these “underwater windmills”.

The marine current turbine SeaGen being assembled.

The 1.2 MW SeaGen tidal current turbine has been developed by leading tidal turbines technology developer Marine Current Turbines Ltd. (MCT) based in Bristol, United Kingdom. The turbine works much like an “underwater windmill”, but is driven by the tidal current rather than air. Unlike wind energy, which is subject to the random nature of the weather, tidal flows are much more predictable. Moreover, due to the higher density of water compared to air, underwater turbines do not need to be as large as wind turbines. SeaGen has been installed in Northern Ireland’s Strangford Lough and is the world’s first commercial tidal current turbine.

Artist’s impression of SeaGen units in the sea.

The SeaGen turbine’s gearbox has been designed by Orbital2 Ltd., a leading UK developer of renewable energy gearboxes and is being manufactured in the Czech Republic by Wikov MGI. The gearbox developers and manufacturers have selected NKE Austria to supply the bearings. Decisive in their choice were NKE’s excellent technical support and short production lead times. “NKE has been a capable and efficient partner in bearing technology. The availability of large main rotor shaft bearings is the decisive factor for this project”, said Dr. Frank Cunliffe, managing director of Orbital2.

NKE supplies nine different types of bearings for the gearboxes, including deep groove ball bearings, tapered roller bearings, cylindrical roller bearings and four-point contact ball bearings, with outer diameters from 300 to 1090 mm.

The tapered roller bearing is one of the NKE bearing types used in SeaGen gearboxes.

Besides bearings for tidal current turbines, NKE supplies bearings for other renewable energy sectors, especially wind energy. By winning contracts worth millions of euros from renowned wind turbine and gearbox manufacturers, NKE has been actively contributing to the development of technologies aimed at reducing emissions.

www.nke.at

Motion Control Tips

Aurora LCOM Spherical Bearings were designed to offer a higher level of performance with dimensional interchangeability for the “LS” spherical bearing category; a market segment which has remained largely unchanged since the 1950s. “LS” bearings are characterized by being of 3 or 4 piece construction, with an inner ball, an outer ring, and a one or two piece brass, bronze, or copper alloy race between. Since the early 1950’s users of these bearings, which are also marketed with a “FLBG”, “RS”, or “VBC” prefix, have had to accept the low strength and poor vibration resistance of these bearings do to the low strength race material. Aurora’s LCOM bearings incorporate superior materials and manufacturing processes to overcome the performance deficiencies associated with “LS” bearings.

www.aurorabearing.com

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The bearings of the planetary gears tend to be highly loaded in this application.  Austrian bearing specialist NKE Austria has developed a modular bearing system that will manage the loads better than other approaches. The system is already in use in the 1.5 MW, 2 MW and 2.5 MW wind turbine gearboxes of a well-known German gearbox manufacturer.

Schematic cutaway drawing shows the two stage planetarygearbox with one spur gear stage (source: Romax/NKE)

The modular concept is based on single-row cylindrical roller bearings of the RN range, which do not have an outer ring. These bearings are equipped with a one-piece solid brass cage, which is guided by the inner ring. The cage features inspection grooves for endoscopic inspection of the inner raceways as standard.

These single row bearings can be assembled to sets of two, three or four bearings to conform with the individual load and design parameters of a specific gearbox.

The tightly toleranced overall height of each individual bearing and their precise matching ensures even distribution of the radial loads. Each bearing set includes the components required to secure the bearings axially in the planetary gears – such as retaining rings and loose rib rings. If required, the overall width of each bearing set can be adapted to the operating conditions and the available space with spacer rings fitted between the individual bearings.

Fourfold planetary gear bearing set.

Used consistently throughout the gearbox assembly, the modular concept has several advantages: simpler design of planetary bearings; a standard bearing design for the first and second gear stage and across various gearbox sizes; reduction in the number of bearing variants; simpler adaptation of bearing set characteristics to the requirements of each gear stage; excellent rolling element guidance, due to the one-piece solid brass cage, even during rapid acceleration; and standard lubrication grooves to improve the lubrication of the planetary gear bearings.

NKE Austria GmbH
www.nke.at

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HPM™

HPF™

Powertech Labs subjected the bearings to accelerated wear testing under dry, wet and low-speed, edge-loaded oscillating conditions, simulating those encountered in actual hydropower turbines. The HPM™ bearings exhibited acceptable coefficients of friction and wear in dry testing, and generally low wear rates in wet and edge load tests. The final test report also cited the material’s robust construction and PTFE brand, self-lubricating properties.

The HPF™ bearings performed extremely well with low friction values regardless of test conditions, according to the Powertech report. Wet and edge-loaded testing yielded extremely low wear rates. Dry wear rates varied somewhat over the course of the testing, but remained well within the specification.

Developed specifically for hydropower applications, GGB’s HPM and HPF materials provide high load capacity, excellent shock and edge loading capacity, low friction, superior wear rate, corrosion resistance and dimensional stability. Because the bearings are self-lubricating, they are also environmentally friendly.

www.ggbearings.com

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Plastic plain bearings can reduce costs by 25% when compared to bronze, metal-backed and custom injection-molded bearings. Eighty percent lighter than conventional steel alternatives, plastic spherical bearings compensate for misalignment errors and edge loads, eliminating the need for costly readjustment, reaming or retrofitting. For linear applications, plastic bearings can potentially cut costs up to 40% as a corrosion-resistant alternative to metal ball bearings. Linear guide systems featuring plastic gliding elements are also a cost-effective choice due to their resistance to dirt, dust and chemicals.

igus® offers 9,600 bearing products ranging from iglide® plastic plain bearings and igubal® spherical bearings to DryLin® linear bearing and slides. Free samples available.

www.igus.com

Motion Control Tips