Broderson IC-280-A, Accompaniment To The Installation, Operation And Maintenance Manual

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2-15
C A U T I O N
A capacity load may be carried on the boom, or a capacity load may be carried on the
deck, but not at the same time. The total of the percent of deck load and the percent
of boom load must not exceed 100%. For example, if the boom load is 100% of its
capacity at its current load radius, the deck load capacity is 0%. If the boom load is
60% of the load rating for its load radius, the deck load capacity is 40% of maximum.
C A U T I O N
The OUTRIGGERS OUT & DOWN capacities of this crane are based on all outriggers
being FULLY EXTENDED to a FIRM, LEVEL surface with no load on the tires. The
crane shall NOT be operated in the following manners:
A. Outriggers only partially spread or tires carrying some load. (If the rear axle can be
oscillated by hand, it is not loaded.)
B. Crane operated on a hill or sloping surface. Crane will tip at less than rated capacity if
crane is not level.
C. Outriggers extended to a surface that appears to be firm, but is unable to support the
outrigger pad at full rated loads. Examples of this type of surface are:
1. Thin or cracked blacktop or concrete.
2. Dirt that appears dry and firm on top but is moist or unpacked beneath the
surface.
3. Dirt with a frozen but thin crust.
CAPACITY EXAMPLE (See Boom Extension Capacity Example Page 2-21)
Refer to the IC-280 capacity chart on the preceding page. A load 6’ X 6’ X 6’ (1.5 m x 1.5 m
x 1.5 m) and weighing 14,000 pounds (6350 kg) is to be lifted onto the deck of the crane for
transport to a new location. We see on the chart that 10,000 pounds (4536 kg) is the
maximum load on one-part line, so the sheave block is required. The charts show the weight
of the standard sheave block to be 300 pounds (136 kg). The rigger says that two slings are
required, weighing a total of 50 pounds (23 kg). The total load is 14,000+300+50=14,350
(6350 + 136 + 23 =6509 kg).
Looking at the 360° ROTATION, ON RUBBER column we see that we can lift 14,800 pounds
(6713 kg) at a 6-foot (1.8 m) load radius. However, this radius is less than the distance from
the center of rotation to the center of the load, with the crane parked next to the load, so the
load cannot be lifted this way. This leaves the ON OUTRIGGERS columns. The outriggers
should always be used whenever possible anyway. We see that we can lift up to 28,000
pounds (12,700 kg) at a 12-foot (13.5 m) load radius, either over the front or over the side. If
possible, position the crane to lift the load over the front. This is the best position for stability.
Checking the chart, we see that the load is within the deck load limit of 14,800 pounds (6713
kg) and that travel speed with the load must be limited to creep speed. Creep speed is less
than 2 MPH (3 km/h) and not to exceed 200 feet (60 m) in a 30 minute period. This is an
approved relationship between load, tire pressure, and speed.
REMEMBER, AS THE BOOM IS LOADED, DEFLECTION OF THE BOOM, TIRES, ETC.
WILL INCREASE THE LOAD RADIUS. SO BE CONSERVATIVE IN YOUR CAPACITY
ESTIMATE.