Pick and Carry Operations Flashcards

During a pick and carry operation on a 3% downhill grade, a crane operator notices the load begins to swing laterally as they travel. Which action should the operator take FIRST?

Answer: Stop travel immediately and allow the load to stabilize before reassessing

When a load begins to swing laterally during pick and carry travel, the operator must stop immediately. Continuing travel while the load swings compounds the dynamic forces on the crane, dramatically increasing tip-over risk. Increasing speed worsens the pendulum effect; applying the swing brake while moving can induce abrupt torque loads; lowering a load while in motion is a prohibited practice. Stopping allows the load to stabilize so conditions can be reassessed before travel resumes.

A rough-terrain crane is rated for pick and carry at 360° with a 40-foot boom at 10 feet of load radius. When the operator extends the boom to 50 feet to clear an obstacle overhead during travel, what is the MOST critical factor that changes?

Answer: The manufacturer's pick and carry rating no longer applies and a new rated capacity must be interpolated from the load chart

Load charts for pick and carry operations are specific to the boom length and radius combinations tested and rated by the manufacturer. Extending the boom mid-travel changes the rated capacity and the stability envelope. The operator cannot simply interpolate informally — a new rated capacity must be identified from the load chart for the new configuration, and if no rating exists for that boom/radius combination during travel, the operation must stop. Side stability does change with boom length, travel speed limits never increase with longer booms, and there is no blanket prohibition solely based on boom-to-radius ratio.

ASME B30.5 requires that during pick and carry operations the load must be carried at the 'lowest possible position.' In practice, how is this requirement best interpreted when the travel path has a 6-inch curb that must be crossed?

Answer: The load may be raised just enough to clear the obstacle, then immediately returned to the lowest safe travel height after crossing

ASME B30.5's 'lowest possible position' standard is a performance-based requirement, not an absolute fixed height. It means the load should travel as close to the ground as conditions safely permit. When a discrete obstacle like a curb must be crossed, the load may be elevated minimally to clear it and must then be returned to the lowest safe position. The standard does not prohibit necessary temporary elevation; it prohibits traveling with loads unnecessarily high. Boom angle thresholds and radius-to-length ratios are not how this requirement is defined.

A crawler crane's pick and carry load chart shows a rated capacity of 18 tons with a 35-foot main boom, traveling on firm, level ground. The actual ground at the job site has been probed and shows a bearing capacity of 1,800 lbs/ft². The crane's ground bearing pressure at maximum rated load is calculated at 2,100 lbs/ft². What must happen before the pick and carry move proceeds?

Answer: Ground improvement or crane mats must be used to either increase bearing capacity or distribute crane load until the ground bearing pressure does not exceed site capacity

Ground bearing pressure exceeding the site's rated bearing capacity is a fundamental hazard in any crane operation, and especially dangerous during pick and carry because the crane is in motion over varying ground. The solution is engineering-based: either improve the ground (compaction, gravel, concrete pads) or use crane mats/outrigger pads to spread the load until bearing pressure is within the site's capacity. Crawlers do distribute load better than outrigger pads, but this does not override a situation where calculated pressure still exceeds site capacity. A 10% de-rate is not a recognized standard fix for ground pressure deficits, and adding a spotter addresses monitoring, not the underlying hazard.

During a pick and carry operation with a lattice-boom crawler crane, the signal person is positioned 30 feet ahead of the crane's travel path. The load begins to travel at an angle toward the signal person due to an uneven track slab. What is the CORRECT action under ASME B30.5?

Answer: The operator must stop on their own initiative without waiting for a signal, because a signal person in the path of travel is an emergency stop condition

Under ASME B30.5, the operator has the authority and obligation to stop crane motion any time an unsafe condition exists, regardless of whether a signal is given. A signal person who is directly in the line of crane or load travel is an imminent danger — waiting for a signal wastes critical time. The operator must initiate an emergency stop on their own initiative. The signal person should also move, but the operator cannot rely on that happening quickly enough. Swinging the boom while traveling compounds the hazard. This question tests knowledge that operators are not passive signal-followers — safety override is always the operator's responsibility.

A pick and carry load chart stipulates a maximum travel speed of 0.5 mph when carrying at 85% of rated capacity. The operator's phone-based GPS shows 0.4 mph. However, the load is visibly bouncing during travel over a smooth concrete floor. Under NCCCO standards, how should the operator interpret this situation?

Answer: The operator must reduce speed further, because load chart speed limits are maximum values that assume ideal surface conditions, not minimum safe speeds

Pick and carry speed limits on load charts represent the maximum allowable speed under ideal conditions — they are not a target or a floor. Load bounce during travel is a warning sign of resonant dynamic amplification, where the travel speed matches or nears the natural pendulum frequency of the suspended load. This multiplies the effective load on the crane beyond rated capacity even within the speed limit. The operator must slow further, and may need to stop and re-rig or adjust the approach. Bouncing is not primarily a rigging defect on smooth floors; it is a travel-dynamics issue. There is no NCCCO minimum speed standard for hydraulic pressure.