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INSPECTING THE LOAD CHAIN
The chain must be inspected at regular intervals, with a minimum of
once annually. As the frequency of use increases, the time intervals
between inspections must be reduced. During inspection, the chain
link must be examined along its entire length, including the hidden
parts. If the lifting equipment is frequently used with a constant lifting
distance or in other words the switch from upward to downward
often takes place in the same area, a particularly thorough
inspection and lubrication is required in that area. Worn chain can
also be an indication of worn hoist components. For this reason, the
hoist's chain guides, hook blocks and liftwheel (sprocket) should be
examined for wear and replaced as necessary when replacing chain.
1. Check to see if chain is dirty or poorly lubricated.
2. Clean the chain with a non-caustic/non-acid-type solvent and
perform a link-by-link inspection for wear or cracks, twisting or
deformation. Replace chain that shows any of these defects.
3. Slack the portion of the chain that normally passes over the lift-
wheel (sprocket) or idler sprocket on multi-reeved hoist. Examine
the chain links for wear (see figure 17). If the wire diameter
anywhere on the link measures less than 90% of the nominal
wire diameter, replace the chain.
Figure 17. Chain Wear Areas
4. Based on ASME B30.16, chain links should also be checked for
elongation. Select an unworn, unstretched length of the chain (at
the slack end, for example). Suspend the chain vertically under
tension and, using a knife blade caliper-type gauge, measure
the outside length of any convenient number of links (11 is
recommended). Measure the same number of links in the used
sections and calculate the percentage in increased length. The
chain should be replaced if the length of the used portion is more
than 1.5% longer than the unused portion of the chain. Also, if
the pitch of any individual link has elongated by more than 5%,
the chain should be replaced.
Figure 18. Chain Dimensions
Table 8. Chain Dimensions
Models
A thru H-2
0 .745" (18.9 mm)
J thru RRT-2
0.858" (21.8 mm)
RRS
1.18" (30.0 mm)
VARIABLE SPEED ELECTRIC CHAIN HOIST WITH
OPTION
P
D
0.250" (6.3 mm)
0.312" (7.9 mm)
0.394" (10.0 mm)
Figure 19. Gaging Load Chain Wear
Figure 20. Chain Embossing
Use only Star (*) grade load chain and original replacement parts.
Use of other chain and parts may be dangerous and voids factory
warranty.
IMPORTANT: Do not use replaced chain for other purposes such
as lifting or pulling. Load chain may break suddenly without visual
deformation. For this reason, cut replaced chain into short lengths to
prevent use after disposal.
Use of commercial or other manufacturer's chain and parts to
repair CM hoists may cause load loss.
TO AVOID INJURY:
Use only CM-supplied replacement load chain and parts. Chain
and parts may look similar, but CM chain and parts are made of
specific material or processed to achieve specific properties.
REMOVAL AND INSTALLATION OF LOAD CHAIN
Improper installation (reeving) of the load chain can result in a
TO AVOID INJURY/DAMAGE:
• Verify use of proper size and type of hoist load chain
for specific hoist.
• Install load chain properly as indicated below.
NOTE: When installing load chain in Models E, H, R and RR by
either of the "starter chain" methods, two loose end connecting
links must be used. Hoist load chain can be installed by any one
of several methods.
Use of commercial or other manufacturer's chain and parts to
repair CM hoists may cause load loss.
TO AVOID INJURY:
Use only CM-supplied replacement load chain and parts. Chain
and parts may look similar, but CM chain and parts are made of
specific material or processed to achieve specific properties.
The first method is recommended when replacing severely worn
load chain and requires disassembling the hoist. Method 2 does
not require hoist disassembly, whereas Method 3 requires only
partial disassembly.
16
dropped load.
P/N: 192047082 (REV AD) 627NH March 2022
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