FULL extension of the vertical jack cylinders should be avoided if not necessary
to level crane and raise wheels clear of ground because oil expansion under
extreme heat conditions can cause cylinder seal failure. Check to ensure that all
beams are fully extended, swinging the upper if necessary to visually check that
each beam reaches full extension. Level the crane using the bubble indicator to
determine when a level condition is achieved. While operating the crane,
frequently check and level the outriggers between lifts.
The operator must exercise sound judgment in positioning the outriggers. The
outriggers should not be set near holes, on rocky ground or on extremely soft
ground. Setting the outriggers in such locations may result in the crane tipping,
causing personal injury or property damage. Where a firm footing or level ground
is not otherwise available, it should be provided by substantial timbers, solid
blocking, or other structural members sufficient to distribute the load so as not to
exceed the safe bearing capacity of the underlying material, and to enable
leveling of the crane.
Proper positioning of the outriggers is critically important to both the safety and
effectiveness of craning operations.
3. Use the load rating chart attached to the crane to interpret the conditions and
limitations that exist when making a lift with the crane. The determining factors are
lifted load, radius, boom angle, working position, hoist line reeving, tire pressure, travel
data, and use of a jib.
The examples given in this section are given for your interpretation of the terminology
used on the chart (see LOAD RATING CHART INTERPRETATION on page 196).
The load rating chart values used in the examples may not be the same as those
on your load rating chart. Use the numbers from the chart attached to your crane
whenever making lift calculation.
The increased possibility for inadequate wraps remaining on the winch drum occurs
when operating with a higher number of parts of line than are required for the load
being lifted, particularly at longer boom lengths and high boom angles.
Sufficient wire rope is initially provided to allow the hook block to reach ground level
when reeved for the required parts of line indicated on the capacity chart for all given
loads. Reeving with more parts of line than required may result in all of the wire rope
being payed off the winch drum.
Always consider, anticipate, and/or determine by trial the maximum amount of
wire rope which will be payed off the winch drum to perform each different
craning application of this crane. Be sure to provide for no less than two full
wraps of wire rope remaining on the winch drum as specified in all applicable
crane operating safety standards.
The intent of this caution is to prevent any possibility of either reverse winding of the
rope on the winch drum, which could cause breakage of the winch rope, or of
189P/N 12261-683 REVISED: January 2015
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