Wire Race Bearings: compact, highly durable, individual

The Franke principle delivers maximum design freedom

In our Wire Race Bearings, the rolling process does not take place directly between the rolling element and the mating structure, and instead with low friction on the race rings. You receive maximum design freedom thanks to their compact and highly durable 4-point contact. You are at liberty to choose whichever material, geometry, size, bore pattern, gear and sealing you require.

Functional principle

Patented Innovation

Franke wire race bearings meet your requirements and are easily adaptable to your mating structure.

An ingeniously simple principle

Our Wire Race Bearings are based on a simple yet ingenious principle: Individual race rings made of wire are fitted with a raceway that is designed precisely to match the diameter of the rolling elements. Therefore, the rolling action does not take place directly between the rolling elements and mating structure, but rather with low-friction on the four open race rings. This engineering principle permits free design of the mating structure in terms of its geometry and material selection.

Compact and lightweight

Wire Race Bearings are extraordinarily compact and fit snug in even the tiniest mounting spaces. They are available either as bearing elements (consisting of race rings, rolling element and cage), or as ready-to-use bearing assemblies together with the mating structure. Their compact form and the free material selection for mating structures permit the construction of lightweight designs whose low masses also require less operating power.

Benefits

Compact design – minimum mounting space

Franke Wire Race Bearings can be integrated directly into your mating design. Our smallest bearing element requires a mere 4 x 7 mm mounting space.

4-point system – resilience from all directions

The arrangement of the race rings ensures even loading resilience of the bearings from all directions. This applies equally to the double row angular contact ball bearings.

Washers
Freely adjustable rotational resistance – a preloaded system

Franke Wire Race Bearings can be aligned and adjusted. This takes place using washers, solid adjustment or adjusting ring.

Solid adjustment
Freely adjustable rotational resistance – a preloaded system

Franke Wire Race Bearings can be aligned and adjusted. This takes place using washers, solid adjustment or adjusting ring.

Adjusting ring
Freely adjustable rotational resistance – a preloaded system

Franke Wire Race Bearings can be aligned and adjusted. This takes place using washers, solid adjustment or adjusting ring.

Angular contact ball bearings for highly-dynamic applications

The race rings in the Franke Wire Race Bearings can be arranged individually and also combined to form multi-row bearings. Arranged as angular contact ball bearings, they become highly-dynamic rotational systems for high-end applications.

  • Circumferential speeds up to 20 m/s
  • Rotational speeds up to 300 rpm
  • Elastomer damping for < 60 db(A) (full load)
  • Integrated direct drive

Free selection of bearing geometry – design your bearings individually

The housing components are not directly exposed to load from the rolling elements and can be constructed with extremely thin walls. This produces compact and lightweight components in conjunction with the small mounting space the Wire Race Bearings require.

Geared outer and inner ring

All gears available in all qualities on request. We also deliver the required pinions or drives.

  • Straight gear
  • Angular gear
  • Toothed belt gear
  • Worm gea
  • Special gear

Free material selection for the mating structure

Franke Wire Race Bearings deliver the requisite rigidity and accuracy of the bearing in almost any mating structure. They carry the principal load. Alternative materials for the mating structure are:

  • Steel
  • Aluminium
  • Cast
  • Bronze
  • Plastic
  • Carbon
  • Non-corrosive
  • Special seals (Viton)
  • Coatings (ZnFe, electroless nickel, ATC)

Depending on the material used the weight savings compared with standard steel bearings can be up to 65 %.

Free material selection of the bearing element

By standard, Franke Wire Race Bearings are manufactured using tough, hard spring steel. Alternatively other materials can be used for special applications, including:

  • Hardened steel
  • Non-corrosive
  • Coatings (ZnFe, electroless nickel, ATC)
  • Non-corrosive balls
  • Ceramic balls
  • Special cages (non-corrosive, hard fabric, brass)
  • Adjusted raceway osculation
  • Adjusted carrying angle
  • Special grease
  • Non-lubricant design

Insensitive to ambient conditions, elastic to shock/impact

The inner elasticity of the open race rings makes Franke Wire Race Bearings insensitive to ambient conditions, including:

  • Temperature fluctuations
  • Pressure differences
  • Housing torsion
  • Vibration

Constructive examples

Angular ball bearing

Bearing diameter 1060 mm

  • Precise large Antifriction Bearings for computer tomographs
  • Elastomer insert beneath race rings for smooth and silent running
  • Low power input and electrical insulation of the inner and outer ring
  • Aluminium mating structure reduces weights and power required

Light weight bearing

Bearing diameter 240 mm

  • Compact, robust bearing element
  • Extremely space saving and light weight design
  • Integrated in filigree aluminium design
  • Threaded ring for adjustment of rotational resistance

Clean room bearing

Bearing diameter 137 mm

  • High stiffness and accuracy due to ground raceways
  • Special materials ensure optimum function (Ematal)
  • Ceramic balls, teflon cage and special lubricant
  • Bearing assembly for the clean room class 10.000

Slim bearing

Bearing diameter 30"

  • Slim bearing type LSA8 with two race rings
  • Easy mounting and manufacturing of the mating structure
  • 4-point-system takes loads from all directions
  • Free selection of material and design of the mating structure

Hubless wheel

Bearing diameter 414mm

  • Double row ball bearing for high stiffness and moment loads
  • Adjustable rotational resistance for smooth and easy running
  • Center-free design to integrate drive and brake systems
  • Small mounting space

Wood industries

Bearing diameter 113 mm

  • Smallest mounting space
  • Favourable price for the complete system
  • No stick-slip-effect and lowest friction
  • Outer ring adjustable individually

Centrifuge

Bearing diamter 280mm

  • Slim bearing type LSA5 in double row design
  • Race rings and balls non-corrosive, protected against cleaning water
  • Easy running and low rotational resistance
  • Smallest mounting space

Angular ball bearing

Bearing diameter 1060mm

  • Precise large Antifriction Bearings for computer tomographs
  • Speed up to 300 rpm
  • Integrated direct drive system optional
  • Small mounting space, direct integration into the mating structure

Multiple bearing

Bearing diameter 930mm

  • Complete customized system including gear
  • Customer receives whole system from Franke
  • Customized solutions available even at one-piece-orders
  • Free selection of the material of the mating structure

Werkzeugwechsler

Lagerdurchmesser: 800 mm

  • Hohe Belastungen aus allen Richtungen werden problemlos aufgenommen
  • Minimaler Einbauraum
  • Hohe Wiederholgenauigkeit
  • Aufwändige Abdichtung gegen Umgebungseinflüsse

Blast furnace

Bearing diameter 850mm

  • Temperature range up to 200 °C
  • Flat cage made of brass for high temperature
  • High radial and axial accuracy
  • Optimum adjustment to all interface dimensions

Indexing table

Bearing diameter 380mm

  • Highest static and dynamic load capacity
  • High accuracy due to ground raceways
  • Minimum mounting space
  • Cost-effective solution to create a directly driven bearing

Ring loader

Bearing diameter 1200mm

  • Special position of wire rings for fast adjustment of rotational resistance
  • Outer gear for belt drive
  • Labyrinth-seal for protection against cooling water
  • Mating structure made of aluminum for light weight and small driving power

Patient bed

Bearing diameter 370mm

  • Mating structure in customized design
  • Minimum mounting space allows slim design
  • Threaded ring for easy adjustment of the rotational resistance
  • Rectangular race ring profile for ease machining of the bearing bed

Precision bearing

Bearing diameter 906mm

  • Precision bearing with ground raceways
  • Suitable for high temperature, flat cage made of brass
  • 60°-angle position of race rings for high radial loads
  • Labyrinth-seal for protection against environmental influences

Circular knitting machine

Bearing diameter 930mm

  • High accuracy for perfect fabric structure
  • Smallest mounting space, direct integration into the mating structure
  • Rotary speeds up to 60 revolutions per minute
  • Best cost-performance-ration due to long lifetime and favourable price

Machinery

Bearing diameter 560mm

  • Classic 4-point-contact-bearing made of steel
  • Ground raceways for high load capacity and precision
  • Divided outer ring for easy adjustment of the rotational resistance
  • Customized design of the mating structure

Tool revolver

Bearing diameter 635mm

  • High precision bearing with axial runout < 0,05mm
  • Labyrinth- and Viton-seal protection against cooling water
  • Plama nitrided surfaces and hardened gear
  • Direct integration into customers design

Aerospace bearing

Bearing diameter 180mm

  • Housing parts made of aluminum for light weight
  • Easy running with rotational resistance <0,5 Nm
  • Insensitive to temperature changes and vibrations
  • Labyrinth-seal protection against environmental influences

Bearing for robots

Bearing diameter 250mm

  • Housing parts made of aluminum for light weight
  • Smallest mounting space for slim design
  • Bearing element type LER3 with rectangular profil for easy mounting
  • Customized design of the mating structure

Medical technique

Bearing diameter 1060mm

  • Precise large Antifriction Bearings for computer tomographs
  • Elastomer insert beneath race rings for smooth and silent running
  • Low power input and electrical insulation of the inner and outer ring
  • Aluminium mating structure reduces weights and power required

Application examples

Hubless rim on a Formula Student race car

Requirements

The aluminium-carbon rim on an electric race car should be designed to accommodate the drive and braking systems in its center. The bearings used must require very little mounting space and possess a large open center. Plus they need to securely transfer substantial forces and torques.

Solution

Franke Wire Race Bearing, integrated directly in the housing components of the rim as double row angular contact ball bearings. The Wire Race Bearing handles the prevalent loads and works independent of the material used in the mating components. The wires and the rolling elements require minimal mounting space.

Advantages

Space-saving bearing solution with large open center. Its arrangement as double row angular contact bearings permits extremely dynamic movement processes.

The video on YouTube

Placement head for printed circuit board production

Requirements

Bearing for a high-performance placement head in printed circuit board production with a cycle frequency of 18 start/stop movements per second and up to 120 million revolutions over five years. The service life is defined as ten years. The bearing must be free from clearance in all directions at 70°C so that the components can be fitted precisely.

Solution

Franke special bearing assembly LDB0110. Aluminium (Dispal) is used as the material for the inner and outer ring. It has almost the same thermal expansion coefficient as steel, facilitating constant unit set values across the entire temperature range.

Advantages

Customer-specific design, which meets all requirements with regard to size, material and mounting dimensions. The integrated bearing element has a small cross section, giving the customer a compact, but nevertheless lightweight design. Franke is the only manufacturer worldwide that can satisfy these specifications.

Rotary index table

Requirements

The bearing used must guarantee smooth and clean operation of the rotary tables in their designated applications, and must also ensure high repeatability precision with simultaneous positioning accuracy. The system moves heavy payloads.

Solution

Bearing elements LEZ with bearing diameter 400 to 1500mm.
Engineered with a variety of wire races and ball combinations.

Advantages

The Franke LEZ bearing elements used are designed precisely to suit the various loads and hence guarantee smooth and clean movements of the rotary tables. Additionally, the 4-point system has no difficulty withstanding the prevailing loads.

Azimuth bearings for solar panels

Requirements

Bearing assembly to swivel the solar panel. Very slow-moving worm gear to follow the path of the sun. High stiffness to cope with any wind pressure.

Solution

Wire Race Bearings as bearing elements.
The system uses wire diameters of 7mm and ball diameters of 20mm to achieve the requisite load rating and stiffness. Other modifications: Special osculation and spherically seated design.

Advantages

Low mounting space thanks to direct integration in the cast housing of the rotary drive. High load rating and stiffness, also attractive series price and other advantages.

Cardanic suspension of an aerial camera

Requirements

Light, customized bearings are required for the articulation of the cardanic suspension; they must possess high stiffness while at the same time remaining smooth and with low breakaway torque and rotational resistance. Forces and torques occur from all directions. The bearings must not impede the camera's imaging quality.

Solution

LDB155 on high-strength aluminium with customized bore pattern. Anodized-orange by request of the customer.

Advantages

Bearing material, design and coating based on customer specifications. The 4-point contact bearing can accommodate forces from all directions and is insensitive to temperature fluctuation and vibrations. Smooth bearing with concomitant, high stiffness, at a favorable price.

The video on YouTube

Tool exchanger

Requirements

The tool exchanger in the machining center houses a bearing assembly to position the various tools in place on the machining head. A high degree of precision is needed to securely grab the tools at any time.

Solution

Franke bearing assembly with gear in a diameter range of 630 to 1092mm.

Advantages

The large open center in the Franke bearing assemblies means that the entire drive system can be moved inside. A labyrinth and a lip seal protect the raceways from chips and coolants. The tool holders are fitted directly to the outer ring. The selected preload ensures high precision and constant rotational resistance for high operating smoothness and precision.

Articulated robot

Requirement

The lightweight robot is used as a service robot and mobile robot. The net weight of the robot is 10kg with a rated load of 3kg. It consists of CFK materials with good rigidity and low mass. Bearings are planned for use in the movement axes. Their main requirements are also high stiffness, low weight and small mounting space.

Solution

Bearing elements in the LEZ64 and LEL84 series.

Advantages

Bearing elements only require minimal mounting space and are built in directly to the design of the robot. The material of the mating structure does not therefore depend on the bearing and can be freely selected. High bearing strength in all directions

Wheel hub and direct drive

Requirements

A concept vehicle is to be motorized by one direct drive unit per wheel. This requires a bearing system with compact mounting space and sufficient load-bearing capacity. The maximum revolutions is 1000 rpm. The balls must be non-magnetic, as they are fitted adjoining the direct drive.

Solution

Four LES0380 – 5/9.525, including ceramic balls.

Advantages

Customized bearings for direct integration in the customer-side design. Accommodation of forces from all sides, including tilting torque. Mounting space designed in cooperation with the customer. Joint assembly of the prototype at Franke.

X-ray device

Requirements

The curved imaging unit of an X-ray device encloses a gurney. This so-called C-arch must be light and evenly shaped, also tiltable by hand.

Solution

Franke Wire Race Bearings as segment bearings.

Advantages

Direct integration of the race segments in the housing components saves space and costs. The segment bearing is set free from clearance and can be moved by hand with a defined resistance. The movement is quiet and even. The 4-point contact bearing easily accommodates the high torque forces in any travel position.

Fan

Requirements

A totally quiet bearing system has to be found for the fan of a living-room ventilator. The bearing must compensate a certain degree of manufacturing tolerance in the injection-moulded housing. The housing is compactly designed; there is only a small mounting space available for the bearing to be used.

Solution

Bearing element LEZ367 with 2.5mm wire races and 6mm balls.

Advantages

In order to further minimize the noise, the ball cage of the bearing unit is only fitted with every second ball. The injection moulded housing was optimized to facilitate series assembly by the customer. The position of the bearing can be adjusted by means of an adjusting ring.

Computer tomography machine

Requirements

The main bearing on the computer tomography machine is one of the elements responsible for ensuring that precise images are delivered. It must run quietly and with low vibrations, even at high speeds. It is necessary to guarantee exact radial and axial run-out.

Solution

A customized, patented Franke Flüsterlager® with elastomer.
Besides excellent running, the Franke CT bearings also come with ideal rotational resistance. The radial and axial run-out is just a few hundredth millimeters, depending on the engineering and diameter. All Franke CT bearings can be calibrated to suit customer specifications. The inner elasticity keeps the bearing outstandingly robust, even when exposed to the toughest conditions of use.

Advantages

Extremely smooth running at up to 300 rpm. The elastomer suppresses the noise generation (60dBA). The bearing possesses a low rotational resistance (< 20Nm) and electrical insulation between the inner and outer ring. Loads in excess of 1000kg are possible.

The video on YouTube

Laseroptik an Luftfahrzeugen

Anforderungen

Es werden Wälzlager mit hoher Steifigkeit und höchster Genauigkeit für den Einsatz zur Flugzeugprotektion benötigt. Die Lager müssen Wärmeausdehnung ausgleichen können.

Lösung

Drehverbindung LDB80/295 als Zylinderrollenlager aus Aluminium mit einem Durchmesser von 295 mm.
Außerdem wird eine weitere Drehverbindung in Form eines Drei-Punkt-Lagers eingesetzt.

Vorteile

Die Drehverbindung LDZ besitzt einen Rund- und Planlauf von 0,03 mm. Eine Gewichtsersparnis wird durch die leichte Aluminium-Konstruktion erreicht. Die Tragzahlen, die Steifigkeit und die Genauigkeit des Lagers sind durch die Laufringe vorgegeben. Das zweite Lager besitzt einen Tragwinkel von 45° (Drei-Punkt-Lager). Der Außenring ist beweglich, um die auftretenden Wärmeausdehnungen optimal auszugleichen.

Das Video auf YouTube

Satellite antenna on seagoing vessels

Requirements

The bearing requires high stiffness across its entire service life (shock stress due to waves and swell). The system must possess non-corrosive properties and provide constant rotational resistance across temperature ranges from –25°C to +60°C.

Solution

The bearing assembly LDA166 in its steel version with adjusting ring, including coating and LER bearing element.

Advantages

The steel solution delivers constant rotational resistance across the entire temperature range. An additional inlet process with readjustment guarantees high stiffness over the whole service life.

Mobile satellite antenna

Requirements

The main bearing for a mobile satellite antenna must not weigh over 1kg. Smooth running with simultaneous tilting stiffness must be guaranteed.

Solution

Franke bearing assembly LDB200 made of aluminium, with inner ring geared on the outside.

Advantages

Complete bearing assembly, ready for installation, made of aluminium and with tooth belt gear. Large open center and low mounting space thanks to the compact structure.

Beverage bottling

Requirements

Precise filling volumes of still water are filled in plastic bottles with the highest standards of microbiological and hygienic safety. The centrepiece of the machine is a filling pipe whose inlet aperture possesses a diameter of between 40 and 100 mm, depending on the size of the bottling system. The carousel is filled via the column. The column is fitted with one locating and one floating bearing, respectively. The bearings used must be lubricant-free and also non-corrosive.

Solution

Franke bearing assembly series LDC 250 as angular contact ball bearing.

Advantages

The bearing assembly is designed to be suitable for food in a non-corrosive version with bearings made of oxide ceramics. The bearing operates with revolutions of 10 rpm and possesses a radial and axial run of 0.03 mm. The bearing absorbs axial forces of 1500 N emanating from the filling pipe. The components are heated to 130°C every 48 hours in order to kill germs. To satisfy hygienic requirements, the bearing assembly is designed to be lubricant-free, i.e. uses a special lubrication with food industry grease.

Circular knitting machine

Requirements

The main bearing in the knitting machine plays a crucial role in the quality of the knitted goods. The highest standards are placed in the precision and operating performance of the bearing, despite the high mechanical and thermal load. The required speeds are up to 60 rpm.

Solution

A ground bearing element from the LEL series with a ball pitch diameter of 400 to 1500mm, made of chromium-silicon, ensures even, smooth running, even in the smallest mounting space. High precision of the bearing in axial and radial runout (<0.03mm) and the outstanding surface quality of the raceways ensure a constantly high quality of the machine.

Advantages

LEL with wire diameter of 4mm, ball diameter of 3/8’’, 8, 10 or 12 mm. The carrying angle is 45°; in special cases even 53°, due to the mainly axial load. Standard speed are at 30 rpm, and up to 60 rpm for smaller ball pitch diameters The axial load caused by the machine cylinder is around 4000N, depending on the machine type.