2.8.4 Winding Drum Machine
Special attention must be given to the drum on this type of machine where drum failures have
occurred. (See Figure 2-16). Be sure to examine the rope fastening in the drum; especially check
the rope clamping to see that clamps are properly installed. (See Figure 2-17 and Table 2-3).
The hammer test of the drum is also very important to determine if there are cracks in the casting.
Be advised, welding is not allowed. Rule 1200.,3 of the A17.1 Code prohibits welding of any
part on which the support of the elevator depends. Closely examine the attachment of the drum
to the drive shaft. Be sure that all fastenings are in their intended place and secured in
accordance with manufacturer's recommendations. Item 104.9 of the A17.2 Manual provides
specific information regarding machine inspection.
2.8.5 Slack Rope Device
Winding drum machines are required to have a slack rope device. There are basically two
types of these devices, one of which is found in the hoistway at the dead end hitch of elevators
roped 2:1. The second type is found at the hoist machine. There are many variations of this type
of switch, depending on the machine design and the particular manufacturer. The switch is
provided to detect slack in the ropes and cause the machine to stop when this occurs. A prime
cause of slack rope is the car hanging up in the hoistway while being lowered. Items 104.10(a)
and 112.4 of the A17.2 Manual describe the procedures for testing the device.
2.9 INSPECTION OF SCREW COLUMN ELEVATORS
The screw column elevator is an uncounterweighted car which is supported by a screw
column and is raised and lowered by screw thread means. Figures 2-18 and 2-19 show typical
screw column elevator applications with component names that will be used in this section. The
location of certain major components of a screw column elevator varies, depending on the design
of that particular elevator. This section will address many of the various arrangements.