Screw Tightening Torques - Schneeberger MONORAIL Series Mounting Instructions

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Appendix
12.2 Screw tightening torques
Maximum tightening torque (Nm)
Screw
Size
Strength class 8.8
12.9
µK = 0.12 (coefficient of friction in head in accordance with VDI 2230)
Tightening torques for guideways and carriages
DANGER!
Risk to life posed by falling machine elements!
In the case of sufficiently high loads, the screw connections are unable
to prevent guideways or carriages e.g. from lateral sliding.
• Profiled linear guideways should be secured using all available
mounting holes and/or threads.
• In the case of high loads, employ constructive measures to prevent
guideways or carriages from sliding (e.g. lateral fixing).
• The recommendations of the screw suppliers must be followed and
are always binding.
• Ensure that the material strength of the connecting structure is
sufficient.
Tightening torques for DIN 912 / ISO 4762 fastening screws
DANGER!
Risk to life posed by falling machine elements!
The friction coefficient μ can be reduced by up to half when greases
are used and screws can fail during tightening.
• The torques must be reduced accordingly.
Lubrication of the fastening screws with grease and tightening using a torque wrench
enables a more even preload force to be achieved. This results in a marked improvement
of running accuracy.
M4 M5 M6 M8
15 15.20 20.25 25-35
3 6 10 25
5 10 16 40
Tightening torques for front plates and additional wipers
See the table below for the maximum tightening torques for fastening screws for the
front plates and additional wipers.
M10 M12 M14 M16
30-45 45.55 55.65 65.100 100
49 83 130 200
81 95 166 265
M20 M24
100
410 700
680 1100
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