Manitowoc National Crane 800D, Operator'S And Service Manual

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OPERATION 800D
2-14
Published 5-27-2018 Control # 039-06
Example 1
A load is to be lifted from the ground and weighs 6120 lb
(2776 kg) at a radius of 35 ft (10.7 m). It will be placed on the
roof of a building at a radius of 25 ft (7.62 m) and a height of
65 ft (19.81 m) above the ground on the opposite side of the
truck.
Step 1. Determine the load.
Step 2. Starting Radius.
Step 3. Ending Radius.
Step 4. Refer to crane Capacity Chart.
Starting point: The boom capacity at a 44 ft (13.41 m) length
and 35 ft (10.7 m) radius is 6300 lb (2858 kg).
Ending Point: The load rating at the ending point is 7100 lb
(3220 kg). The boom will be at 100 ft (30.48 m) extension
and the loaded radius is 25 ft (7.62 m).
The crane has enough capacity at each end of the lift to allow
the lift to be made.
In order to get the load on the roof, the load must be hoisted
from the ground, swung around the rear of the truck
(deadspot in rotation is over the cab) and boom extended to
full 100 ft (30.48 m). At this point measure to ensure load is
at 25 ft (7.62 m) radius. Raise or lower boom to achieve
radius. Hoist load to a height that will clear the top of the
building and rotate to the point load is to be placed. Lower
the load using the hoistline to the roof.
Step 5. Lastly refer to hoist Capacity Chart.
• Crane is reeved for single part line.
• Allowable load for single part line is 7700 lb (3492
kg) well above the 6300 lb (2858 kg) to be lifted.
Operator should now proceed to lift the load as smoothly as
possible.
Example 2
Assume a load of 9000 lb (4082 kg) at 10 ft (3.04 m) radius
on the ground beside the truck to be picked up, swung over
and placed on the truck bed at an 8 ft (2.43 m) radius from
the crane. Crane is reeved for single part.
Step 1. Weight of load and load handling equipment.
Step 2. Starting Radius.
Step 3. Ending Radius.
Step 4. Refer to crane Capacity Chart.
The crane capacity at the 10 ft (3.04 m) point is 25,500 lb
(11 567 kg). Of course, at the 8 ft (2.43 m) radius, the
capacity would be substantially more. Therefore, the crane
capacity is adequate.
Step 5. Refer to hoist Capacity Chart.
The capacity of a 1 part line is 7700 lb (3492 kg), which is
less than load to be lifted. Crane must be revved for 2 part to
lift the 9000 lb (4082 kg) load.
Note: Two part hoist capacity is 15,400 pounds (6985 kg).
Actually when one puts on the 2 part block, the load block
weighs approximately 305 lb (138 kg) rather than the 150 lb
(68 kg) figured in Step 1 so actual load lifted is 9355 lb (4343
kg). Load [9000 lb (4082 kg)] + 2 part block [305 lb (138 kg)]
+ slings [50 lb (22.67 kg)].
Load =
1 Part Load Block =
Sling =
6120 lb
150 lb
30 lb
(2776 kg)
(68 kg)
(14 kg)
6300 lb (2858 kg)
Given = 35 ft (10.7 m)
Given = 25 ft (7.62 m)
Load =
1 Part Line Block =
Slings =
9000 lb
150 lb
50 lb
(4082 kg)
(68 kg)
(22 kg)
9200 lb (4173 kg)
Given = 10 ft (3.04 m)
Given = 8 ft (2.43 m)
Fo
r
Reference
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