Milwaukee 9561 Maintenance, Overload Limiting Protection, Inspections, Lowering Without Power

Milwaukee Electric Tool Corporation

13135 West Lisbon Road

Brookfield, Wisconsin 53005

TEL: (800) 729-3878

Do not use hoist to lift, support or otherwise transport people.

11.Do not operate unless hook travel limit devices function. Test without load each shift.

12.Do not operate when hoist is not centered over load.

13.Do not operate if chain is not seated properly in sprockets or sheave grooves.

14.Do not operate damaged or malfunctioning hoist.

OVERLOAD LIMITING PROTECTION

This hoist is equipped with a factory-calibrated overload limiting clutch that will permit the lifting of loads within its rated capacity, but will prevent the lifting of damaging overloads while the hoist is being operated. If the load being lifted exceeds the lifting capability of the overload clutch, the hoist motor will continue to run, causing overheating of both the clutch and hoist motor. This condition should be avoided by immediately releasing the “UP” button and reducing the load to within the rated capacity of the hoist. See GEARING, page 10, for additional instructions on this device.

The overload limiting clutch is an emergency protective device and should not be used to measure the maximum load to be lifted, or to sense the overload imposed by a constrained load. While the overload limiting clutch will protect the hoist from damaging overloads, it will not ensure that a load is within the rated capacity of the hoist.

MAINTENANCE

INSPECTIONS

A planned inspection routine should be established for this hoist based upon frequency of use, severity of use, and environmental conditions, (Reference ASME Standard

B30.16). Some inspections should be made frequently (daily to monthly) and others periodically (monthly to yearly). It is strongly recommended that an Inspection and Maintenance Check List and an Inspector’s Report, similar to those shown in Figures 10A and 10B, be used and filed for reference. All inspections should be performed or overseen by a designated inspector. Special inspections should be made following any significant repairs or any operating occurrence leading one to suspect that the hoist’s capability may have been impaired.

LOWERING WITHOUT POWER

If the power fails with a load suspended, the hoist will automatically stop. In an emergency the load can be lowered without power as follows:

1.DISCONNECT HOIST FROM POWER SUPPLY AND REMOVE ELECTRICAL COVER.

2.Open disc brake manually by using two screwdriver blades, one on each side of the brake at a point close to the brake spring posts. Apply pressure to the underside of the armature plate (points “X”, Figure 6, page 9) to close the solenoid and release the brake.

Do not allow screw driver blades to touch rotating friction disc “C”.

Do not allow the load to descend rapidly. This causes the motor to race and serious damage may result.

3.Use several quick releases instead of holding brake open continuously. Do not exceed normal lowering speed.

HOOKS

Refer to Figure 2.

1.Inspect hooks once daily for cracking, extreme wear or spreading. Replace hooks showing any of these signs. If the throat openings are spread wider than the maximum permissible 15% increase listed here, the hooks have been overstressed and must be replaced. Any hook that is bent or twisted more than 10° from the plane of an unbent hook must also be replaced.

2.The hook latches should be inspected to ensure that they close the hook throat opening in a secure manner when a load is applied. Inspect the hook shank and nut for any stripping of the threads or other damage. The hook nut should be fully restrained by the retaining pin.

3.In addition to above, load hooks should be inspected for cracks by the magnetic particle, dye penetrant or other suitable crack testing inspection method. This should be done at least once a year.

Figure 2 — Hook

Inspection

		“X” Dimension*
Hoist	Top	Bottom
Capacity	Hook	Hook
1 Ton & Under	111/32"	17/32"
2 Ton	111/32"	111/32"

(*) Maximum permissible throat opening of hook.

6