Quantcast Inspection of Winding Drum Elevators

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2.8 INSPECTION OF WINDING DRUM ELEVATORS
2.8.1 Scope
This section will address the special considerations that are associated with winding drum
machine elevators. (See Figures 2-14 and 2-15). The use of winding drum elevators has been
restricted to freight elevator applications with a rated speed of 50 feet per minute or less, (a rise
of not more than 40 feet), and shall not have counterweight. However, there are drum machine
elevators that were installed prior to this application requirement.
2.8.2 Wire Rope Inspection
Item 103.3(g) of A17.2 Manual states that wire ropes have to be refastened every 12 months
for drum machines located over the hoistway and every 24 months for basement machine
applications. The intervals for refastening on winding drum driving machines with 1:1 roping
are based on fatigue developing in the section of rope adjacent to the babbitted rope socket due to
the bending encountered by the wires as a result of vibration being dampened at this location or
due to stress of a torsional nature that occurs at this point as a result of changes in tension on the
ropes. This problem is more apt to be encountered where a rope socket is employed, but can also
develop with attachments of any type. If the hoisting ropes are not refastened at the interval
specified by this rule, a dangerous situation could occur. On winding drum driving machines
with 2:1 roping there is no requirement to refasten the hoisting ropes periodically as there is no
fatigue developed in the rope section adjacent to the babbitted rope socket. Also, at least one
turn of rope must remain on the drum when the car is resting on a fully compressed buffer. The
broken wires per strand requirement is also modified. See item 103.4(b) of A17.2 Manual for
details.
2.8.3 Normal And Final Stopping Devices
On winding drum machines, normal and final terminal stopping devices are found on the hoist
machine. The code does allow normal limits to be located in the hoistway, but most will be
found on the machine. The machine devices are either sized to interrupt power lines feeding the
hoist motor or of a pilot contact design that will open the motor control switch circuit. The
use of the pilot contact approach is only allowed where the drive machine brake is a direct circuit
controlled device. Items 103.7, 103.8, and 104.10 of A17.2 Manual provide specific information
about these devices.
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