Maintenance And Lubrication - NTN-SNR LINEAR AXIS AXC Series Manual

4.

Maintenance and lubrication

4.1 General information
Caution!
All maintenance and service works must be carried out in power off and secured stage.
The motor housing can reach high temperatures during operation.
4.2 Lubrication
For the reliable operation of the Linear Axis, a sufficient lubrication is essential.
The lubrication should ensure a lubricant film (oil film) between rolling elements and raceways of the guiding and drive elements to
prevent wear and premature fatigue of the components.
In addition, the metallic surfaces are protected against corrosion. Furthermore, the lubricant film allows a smooth sliding of the seals
on the surfaces and reduces also the wear of them.
Insufficient lubrication not only increases the wear, it reduces also significantly the life time.
An optimal selection of the lubricant has a decisive influence on the function and life time of the Linear Axis. In order for the function of
the system to be not affected and remain over a long period lubricated according to the environmental conditions; specific requirements
should be defined.
Such environmental conditions and factors may be for example:
• High or low temperature
• Condensation and splash water effects
• Radiation exposure
• High vibration stress
• Use under vacuum conditions and/or in clean rooms
• Applying of special substances (for example, vapors, acids, etc.)
• High acceleration and velocity
• Continually short stroke movement (< 2 x carriage length)
• Dirt and dust
4.3 Lubricants
There are several types of situational lubricants for the different guiding and drive systems of the Linear Axis.
The lubricants have the following functions:
• Reduction of the friction
• Reduction of the starting moment
• Protection against wear
• Corrosion protection
• Noise reduction
Linear guides and ball screws
Lithium soap greases with the marking KP2-K according to DIN 51825 and NLGI class 2 according to DIN 51818 with EP additives
are to be used under normal conditions.
Specific requirements under special environmental conditions require the selection of a corresponding suitable grease.
In general the compatibility of the lubricants must be checked with each other or with the corrosion protection oil.
Table 4.1 provides an overview of the lubricants used by NTN-SNR for linear guides and ball screws. The use of greases containing
solid additives (for example, graphite or MoS2) is not allowed.
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