milwaukee
lever hoist.qxd
8. Check for damage to the hooks, hook retaining nuts,
collars, pins, welds or rivets used to secure the retaining
members. Dye penetrant, magnetic particle or other
suitable crack detecting inspections should be performed at
least once a year.
9. Check to see if load chain stop is in place and properly
secured.
10. Check for damage of supporting structure.
11. Check for warning labels required by ASME B30.21.
Any deficiencies noted are to be corrected before the hoist is
returned to service. External conditions may show the need for
more detailed inspection which, in turn, may require the use of
nondestructive type testing.
Any parts that are deemed unserviceable are to be replaced
with new parts before the unit is returned to service. It is very
important that the unserviceable parts be destroyed to prevent
possible future use as a repair item.
When the lever hoist is subjected to heavy usage or dusty,
gritty, moist or corrosive conditions, shorter time periods must
be assigned. Inspection must be made of all parts for unusual
wear, corrosion or damage, in addition to those specifically
mentioned above.
HOOK INSPECTION AND MAINTENANCE
Hooks damaged from chemicals, deformations or cracks, or
that have more than a 10 degree twist from the plane of the
unbent hook, excessive opening or seat wear must be
replaced.
Hooks that are opened and allow the latch to disengage the tip
must be replaced.
Any hook that is twisted or has excessive throat opening
indicates abuse or overloading of the unit. As a result, other
components of the hoist could be damaged.
The chart in Figure 4 should be used to determine when the
hook must be replaced. To measure the throat opening,
depress the latch against the hook body (See Figure 4).
Figure 4
Measure Opening
Hook Throat Opening
Hoist
Rated Load
Tones (Kg)
3/4 (750)
1½ (1500)
3 (3000)
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Page 7
Replace Hook
When Opening
is Greater Than:
1¼" (31.8 mm)
1
3
/
" (34.9 mm)
8
1
23
/
" (43.7 mm)
32
Check to make sure that the latch is not damaged or bent and
that it operates properly with sufficient spring pressure. Spring
pressure keeps the latch tight against the tip of the hook and
allows the latch to spring back to the tip when released. If the
latch does not operate properly, It should be replaced.
LOAD CHAIN
Cleaning and Inspection
Clean the load chain with a non-acid or non-caustic type
solvent then slack the chain and make a link-by-link inspection
of nicks, gouges, twisted links, excessive wear or stretching.
Worn chain should be gaged throughout it's entire length and
replaced if beyond serviceable limits.
To determine if the load chain should remain in service, check
gage lengths as indicated in Figure 5. A chain that is nicked,
gouged, twisted or worn beyond length indicated, should be
replaced before returning hoist to service. Chain should be
clean, free of twists and pulled taut before measuring. In cases
where the wear is localized and not beyond serviceable limits,
it is sometimes possible to reverse the load chain, end for end,
and allow a new section to take the wear. Proper installation of
the load chain is covered in the section on Reeving Load
Chain.
Figure 5
Number of
Links in Gage
Hoist Rated
Chain Stock
Load
Diameter
No. of Links
Tons (Kg)
In. (mm)
3/4 (750)
0.236 (6)
1½ (1500)
0.281 (7)
3 (3000)
0.394 (10)
NOTE: Worn chain can be an indication of worn hoist
components. For this reason, the hoist's chain guide roller and
liftwheel should be examined for wear and replaced as
necessary when replacing worn chain.
Load chains are specially heat treated and hardened and
should never be repaired.
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.
7
Gage
Length
Max. Length
allowable for
to Gage
Used Chain
11
8
11
/
" (212 mm)
32
11
9
23
/
" (247 mm)
32
11
13
29
/
" (353 mm)
32