High Speed, High Load Capacity: Bearings for Screw Drives
Universal bearings BSB..-SU-XL for high speed screw drives
Features of the new design
Through the use of state-of-the-art manufacturing techniques, axial angular contact ball bearings BSB..-SU-XL in new design have the following features:
■ Optimised contact face between the rolling elements and raceway
■ Increased raceway accuracy and raceway quality, with a resulting reduction in the stress conditions present on the rolling elements and raceways.
Technical advantages of the new design
The improved features offer a range of advantages:
■ High dynamic load carrying capacity and high speeds due to optimised contact faces
■ Long grease operating life as less strain is placed on the lubricant
■ Low bearing temperatures and high limiting speeds due to reduced friction
■ High energy efficiency of the bearing arrangement due to lower frictional power
High basic load ratings C, longer rating life Lhr
The basic dynamic load ratings C are around 10% higher than those of the previous bearing designs. This also has the effect of increasing the basic reference rating life Lhr by up to 33%. As a result, the operating life of the bearings is extended under identical operating conditions. If the rating life values are maintained, alternatively, higher loads can be applied to the bearing arrangement.
Long grease operating life
In addition to the improvement to the surfaces, the material used for the bearing rings is also subjected to special heat treatment. As a result, the raceways of the inner and outer rings are more resistant to solid particles and under mixed friction. This in turn extends the grease operating life, as less strain is placed on the lubricant. In short, this heat treatment measure leads to a significant increase in bearing rating life in the design compared to the previous design.
Low bearing temperatures and high speeds
The reduced bearing friction in axial angular contact ball bearings BSB..-SU-XL of X-life design and the associated reduction in heat generation in the bearing permit high speeds.
Customer benefits of the new X-life design
The specified technical advantages of axial angular contact ball bearings BSB..-SU-XL in the X-life design result in a variety of customer benefits:
■ Increased productivity
■ Extended maintenance intervals for higher machine availability
■ Reduced energy consumption and lower operating costs
■ Additional degrees of freedom and design possibilities for the new design of the bearing arrangement: Choice between a longer rating life or a higher load.
Modular concept offers standard designs
The customer can select three different designs from one modular concept:
■ Open bearings, not greased, suitable for oil lubrication or grease filling by the user
■ Bearings with minimal gap seal on both sides, greased for life
■ Open bearings, greased with multipurpose grease Arcanol MULTITOP (available by agreement).
Sealed bearings BSB..-2Z-SU-XL offers all sizes in an X-life design with integral minimal gap seal (suffix 2Z). Advantages in detail:
■ They are supplied greased with the multi-purpose grease Arcanol MULTITOP for optimum running characteristics, low friction and long operating life.
■ Protection against the loss of grease and ingress of contaminants.
■ Protection against contamination of bearings during mounting. In contrast to open bearings, initial greasing by manual means is not necessary.
■ The FKM minimal gap seals have strong chemical resistance to environmental influences, such as synthetic cooling lubricants, oils and greases.
Bearing sets with variants of axial angular contact ball bearings
Axial angular contact ball bearings BSB..-SU-XL can be combined individually by the user in bearing sets. As a result, they offer considerable advantages in terms of availability, stockholding and inventory optimisation.
Simple mounting of bearings
The arrow markings on the lateral surface of the bearing outer rings indicate the contact angle arrangement and give the fitter a simple means of assembling the bearings in the correct combination, Figure 4.
The correct mounting position can be seen not only from the arrow markings but also from the different seal colours. As a result, the contact angle pattern can be seen and checked at any time even in the mounted condition.