Harrington Hoists and Cranes TCR Hoist - (1/4-6 Ton) User Manual
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37
f.
When the load limiter is adjusted and working properly, the hoist will operate and lift the load a
short distance before the load limiter automatically stops lifting.
2)
Refer to Figure 7-1. Loosen the lock nut and slowly turn the adjustment screw OUT until it is loose
and no longer is in contact with the internal load limiter spring – as this occurs the screw should
become easier to turn. Stop turning the screw once it is loose and easier to turn.
3)
Turn the adjustment screw IN just enough so that it begins to contact the internal load limiter spring
– as this occurs the screw should become slightly harder to turn.
4)
Put a load equal to the desired actuation point on the hoist's hook (do not exceed 125% of the
hoist's rated capacity). Begin to slowly lift the load, then increase the lifting speed. Return the load
to its resting position so the load chain is not under tension.
5)
If the load limiter prevents lifting, turn the adjustment screw IN one full turn.
6)
Repeat steps 4 and 5 until the load limiter allows lifting.
7)
Turn the adjustment screw OUT ¾ of a turn.
8)
Attempt to lift the rated capacity load again, beginning slowly, then increasing the lifting speed.
9)
If the load limiter does not allow lifting, then turn the adjustment screw IN ¼ turn.
10)
Repeat steps 8 and 9 until the load limiter allows lifting.
11)
Turn the adjustment screw IN ¼ turn. Then, while holding the adjustment screw, tighten the lock
nut to secure the setting.
Turning the adjustment screw IN 8 full turns or more will disable the load limiter.
7.2
Brake
7.2.1
The hoist brake is not adjustable.
7.2.2
Inspect the brake disc in accordance with
Section 5.7
,
Table 5-3
.
7.2.3
The following is the hoist brake inspection procedure. Refer to
Figure 7-2
.
1)
HAZARDOUS AIR PRESSURE IS PRESENT IN THE HOIST, IN THE
SUPPLY OF COMPRESSED AIR TO THE HOIST, AND IN THE CONNECTIONS BETWEEN
COMPONENTS. Shut off the air supply and stop the airflow completely. Lock out and tag out in
accordance with ANSI Z244.1 “Personnel Protection -Lockout/Tagout of Energy Sources”.
2)
Gradually back out all four hex socket cap screws (A) from brake cover (B) from gear case (J) to
slowly decrease spring tension (K) of brake piston (D) against brake disc (I).
3)
Remove brake cover (B) from top of gear case (J). Keep brake piston (D), springs (K), seals and
piston cover (C) together inside the brake cover. Do not remove cap screws (E). Set parts aside
for reassembly.
4)
Remove retaining ring (F) on pinion shaft (H) adjacent to brake disc (I).
5)
Remove brake disc for inspection and measurement and then the two keys (G) from each side of
pinion shaft (H). Refer to "Motor Brake" in Table 5-3, "Hoist Inspection Methods and Criteria".
6)
Prior to reassembly, clean all surfaces of debris, dirt and loose paint. Apply a light film of grease to
all "O"-ring seals.
7)
Reassemble in reverse order. Keep the small hole on the back of the brake piston (D) aligned
toward the top of the hoist. Torque all mounting hardware evenly during the reassembly process.