Super precision bearings

Bearings for main spindles

General features

Design variants

Bearings for main spindles are available as:

• super precision angular contact ball bearings ➤ Figure
  • single row, as single bearings or in sets
  • contact angle 15°, 25°
  • with large or small balls
  • rolling elements made from rolling bearing steel or ceramic
  • rings made from rolling bearing steel or Cronidur 
  • Direct Lube bearings 
• super precision cylindrical roller bearings ➤ Figure
  • single row
  • double row
  • rolling elements made from rolling bearing steel or ceramic 
  • cages made from brass, polyamide or PEEK
• super precision axial bearings , i.e. super precision axial angular contact ball bearings 2344 ➤ Figure, super precision angular contact ball bearings BAX ➤ Figure
  • double direction 
  • contact angle 30°, 40°, 60° 
  • rolling elements made from rolling bearing steel
  • rings made from rolling bearing steel 
  • cages made from brass, laminated fabric

Super precision angular contact ball bearings

FAG super precision angular contact ball bearings are single row angular contact ball bearings with solid outer and inner rings, and ball and cage assemblies with solid window cages ➤ Figure. The dimensions are standardised.

Suitable for applications with very high guidance accuracy

Due to their very narrow tolerances, the bearings are particularly suitable for applications involving the highest requirements for guidance accuracy, rigidity and speed suitability, such as bearing arrangements for main spindles in machine tools.

The product range of super precision angular contact ball bearings is presented in the product tables ➤ link. In addition to the products listed therein, further designs are available by agreement.

Universal super precision angular contact ball bearings (universal spindle bearings) α =  nominal contact angle Fa =  axial load Fr =  radial load   Spindle bearing with balls made from rolling bearing steel   Spindle bearing with balls made from ceramic   Direct Lube spindle bearing

Extensive range for main spindle bearing arrangements, primarily in machine tools

This extensive product range gives the designer all possible scope for designing technically innovative, operationally secure and economical bearing arrangements. This results in significant performance improvements and cost savings as standard in machine tools. However, other machines, such as turbochargers for example, can benefit from these bearings.

Increased performance

In new designs, this can allow the machine manufacturer to achieve a unique position in the market. In existing designs too, refitting with FAG spindle bearings can still give further increases in the performance and profitability of machines.

Super precision cylindrical roller bearings

Features

FAG super precision cylindrical roller bearings comprise solid outer rings, solid inner rings with a tapered bore (taper 1:12) and cylindrical roller and cage assemblies with cages made from polyamide, brass or PEEK (polyetheretherketone) ➤ Figure. The outer ring is removable and can thus be mounted separately from the rest of the bearing package. The inner ring is only removable in the case of series NNU49.

FAG super precision cylindrical roller bearings are also available by agreement with a cylindrical bore.

Super precision cylindrical roller bearings Fr =  radial load   Single row, tapered bore, N10   Single row, tapered bore, ceramic rolling elements: HCN10   Double row, tapered bore, NN30, NNU49

Areas of application

The single and double row bearings are used when the very highest precision is required under very high radial load. Typical areas of application include machine tools and printing machinery. The bearings facilitate bearing arrangements with very high precision, high radial rigidity and very high load carrying capacity. In machine tool building, they provide radial support for the main spindle.

Ideal non-locating bearings

Since variations in length during rotary motion can be compensated between the rollers and the ribless raceway without constraining forces, the cylindrical roller bearings are highly suitable as non-locating bearings. Axial forces are supported by axial bearings, such as double direction axial angular contact ball bearings or super precision angular contact ball bearings BAX. The standard series N10, HCN10 (single row) and NN30, NNU49 (double row) are an established part of the FAG super precision range ➤ link.

Diameter ranges not shown in the catalogue are available by agreement.

X-life premium quality

The super precision cylindrical roller bearings N10 and NN30 in the X-life design have a higher load carrying capacity and thus a significantly increased bearing rating life. A newly developed plastic cage gives lower friction than the previous standard design with brass cage.

Increased customer benefits due to X-life

The advantages of this bearing design include:

• limiting speeds up to 35% higher
• running temperatures up to 12 K lower
• lower noise level
• lower lubricant demand
• longer grease operating life
• higher basic load ratings
• longer operating life of the bearings

The basic dynamic load ratings C are up to approx. 20% higher than those of the previous bearing designs and the basic bearing rating life L₁₀ is up to 65% longer than the previous standard. As a result of the increase in the basic bearing rating life L₁₀, this gives a longer operating life of the bearings under the same operating conditions. If the rating life values are maintained, alternatively, higher loads can be applied to the bearing arrangement.

Super precision axial bearings

Super precision axial angular contact ball bearings  2344

Suitable for applications with very high precision and high axial loads

Double direction axial angular contact ball bearings of series 2344 in particular are very axially rigid super precision bearings preloaded clearance-free with restricted tolerances to class SP. The bearings are used when very high precision is required under high axial load.

Axial angular contact ball bearing 2344, double direction α =  nominal contact angle Fr =  radial load Fa =  axial load

Features

These bearings without self-retention comprise solid shaft locating washers, a spacer ring, a housing locating washer and ball and cage assemblies with solid cages ➤ Figure. The bearing parts are matched to each other and can be fitted separately, but must not be interchanged with parts from other bearings. Available designs of series 2344 ➤ link.

Contact angle

Due to the contact angle of 60°, they can support high axial loads from both sides.

Super precision angular contact ball bearings BAX

Suitable for applications with high speeds and axial loads

Increased load carrying capacity normally brings with it a reduction in the maximum speed. Through the use of angular contact ball bearings BAX, it is possible to unify both requirements. Angular contact ball bearings BAX:

• can support high axial loads
• have similarly high limiting speeds to X-life cylindrical roller bearings
• have high rigidity
• can support axial loads only

The super precision angular contact ball bearings BAX conform to the accuracy class P4S and are generally supplied as ready-to-fit sets in the arrangement DB ➤ Figure. Available designs ➤ link.

Angular contact ball bearing BAX, ready-to-fit set in O arrangement α =  nominal contact angle Fa =  axial load

Contact angle

Super precision angular contact ball bearings BAX are available with a contact angle of 30° for high speed requirements or, for even higher rigidities, also with a contact angle of 40°. As a bearing set, they can support high axial loads from both sides.