07-21-2017 05:49 PM
We operator several deck barges with excavators of various sizes on the deck to perfrom rock placement work, dredging and other general digging and lifting tasks. There is an increased safety focus and our internal engineering group has to perform stability analyses of each barge with the machine. One of the stability criteria is to "not exceed the manufacturer's out of level limits" while lifting. The load charts for the excavators generally say "The above loads are in compliance with hydraulic excavator lift capacity ratings standard ISO/DIS 10567, they do not exceed 87% of hydraulic lifting capacity
or 75% of tipping capacity. Weight of all lifting accessories must be deducted from the above lifting capacities." Other manufacturer load charts also include statements regarding "level surface." When an excavator operates on a barge, the surface is firm (the steel deck and timber mat), but not always level. Due to the lifting, bucket force, excavator position, etc., the barge will heel and trim as it reacts to the weight changes. We typically see heel and trim < 5 degs. Does CAT have an out-of-level standard for excavators that the load charts are good for without derating?