7. Life phases
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7.3.1 Synchronous operation of lifting columns
In an ideal case, two or more lifting columns are parallel to each other and run up and down
synchronously. In reality, there are numerous factors which do not allow this simple way of
considering the problem. Production tolerances are unavoidable when manufacturing lifting
columns, as well as their own construction components. In the worst case, the tolerances for
various components may be cumulative and lead to twisting and damage.
7.3.2 Different heights
A rigid connection between lifting columns at the same
height is essential. If the table frame is firmly bolted down,
the lifting columns are tensioned. Consequently, the
running properties deteriorate and the lifetime is reduced.
The cause of different heights is usually an uneven base.
Therefore, the baseplate of the lifting column should be
variable in height.
However, it is also possible that production tolerances mean
that the lifting columns are at different heights when closed
together. In this case, the limit switches on some lifting
columns can be adjusted for height.
7.3.3 Parallel alignment
If the lifting columns are not parallel to each other, then the
distance between the top fastening points changes during
motion. However, a rigid connection keeps this distance
constant. The consequence is that considerable forces act on
the lifting column guide, which can be damaged by this.
In this case, the lifting columns should also be aligned
exactly. Uneven floors can be compensated by using an
adjustable baseplate.
7.3.4 Bends in the table frames
Table frames are generally made of welded steel tubes and
connection plates for connecting to the lifting columns. If
the connecting plates are not flat against the lifting column,
then the synchro system is stressed during screwing. This
generates unwanted shear forces which stress the lifting
column guide. Please ensure that the components are
working perfectly.
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