Load specifications
Profiles combined with nuts
The profiles are designed for different strength and deformation requirements. Will your profile structure
withstand the loads it is meant to support? Use our quick and convenient online deflection calculator to
calculate the deflection of mk profiles as a function of load (see page 13).
Light duty and extra light duty profiles have a reduced pull-out strength, so longer nuts should be used.
Nuts that have a smaller contact surface compared to standard nuts also have a lower pull-out strength.
The following table serves as a rough guide as to how the pull-out strength changes with different
profile–nut combinations, using the example of an M8 nut in Series 40 and 50 profiles.
80
3
Choosing a Connection
Connecting Elements
Nut 1
34.01.0001
Swivel-in nut
34.16.0831
Slot nut
34.03.0002
T-nut
34.06.0002
mk 2000 (50x50) 100 % (4 kN) 75 % 75 % 66 %
mk 2014 (50x50) light duty 75 % 66 % 50 % 33 %
mk 2002 (50x50) extra light duty 25 % 25 % 12.5 % 12.5 %
mk 2040.01 (40x40) 100 % (4 kN) 66 % 50 % 33 %
mk 2040.40 (40x40) light duty 66 % 50 % 25 % 25 %
mk 2040.31 (40x40) extra light duty 50 % 25 % 12.5 % 12.5 %
Screw connection on the profile face
For threads cut/formed directly into the profile, we recommend a screw depth of 2x the thread size. If the
bore cannot be fully tapped (e.g. the centre bore in Series 60), you must reduce the load capacity.
Angles
Angles can be used to transfer loads from the screw connection. Angles with keys are recommended
because they have machined contact surfaces, engage positively and are easier to mount.
Ribbed washer
The teeth on a ribbed washer cause plastic deformation of the screw head contact surface, pressing into
the material. This provides a strong screw connection that can withstand dynamic loads. If you disassemble
and reassemble the connection multiple times, you should replace at least the ribbed washer to
ensure that the locking function is maintained. For applications with vibrations and highly dynamic loads,
you should additionally secure the screws with thread-locking adhesive (e.g. Loctite).