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July 9,
2009
Engineered Lifting Systems
Tech-Bulletin for
Patented Track Castellated Beams
This bulletin is generated as reference and
notice for anyone that has any brand of patented
track (also called hardened track) with a
castellated (window) construction, or “skip
welded” beams. These tracks have the appearance
of windows, or sections of the web removed, or
the bottom flange is not continuously welded to
the web material.


Originally created as a measure to reduce the
cost to manufacture and/or decrease the amount
of steel used, these beams were predominantly
designed for hand pushed operation cranes and
trolleys. Later, many systems were applied with
motorized drives for bridge and trolley
applications in the work place. The majority of
these systems are well over 45 years old.
Engineered Lifting Systems, along with OEM
patented track manufacturers, strongly suggest
that plants using this style of track make plans
to replace any patented track castellated or
stitch welded beams with new full weld full web
patented track rail.
These beams have a history of failure without
going to plastic deformation, instead just
dropping the hoist/trolley and load. This
happens for a number of reasons, but typically
because of the general beam design. Web buckling
will cause over stressing of the bottom flange,
bottom flange welds failing, or cycle life of
the high carbon bottom flange.

The green arrows in the above picture show where
the bottom flange section was previously welded
to a window beam section.

The red arrows show where an entire section of
the bottom flange failed under load.

Another stitched welded patented track beam
failure.
If you have either castellated track or stitch
welded patented track, we recommend that you
inspect your track to start, and develop a plan
for replacement of these tracks. For additional
information please call Eric Brown at Engineered
Lifting Systems 866-756-1200, or e-mail at
ebrown@engineeredlifting.com |