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NCCCO Core Exam Outline
Timber or steel - Answer- These materials should be used when setting up on soft surfaces such as soft ground, asphalt or backfilled material Over the corner - Answer- On crawler cranes, which boom position creates the greatest ground pressure Blocking - Answer- Allows the weight of the crane and load to be distributed over a greater surface area. Should be used under outrigger floats at all times. 3 - Answer- Blocking should be at least how many times the surface area of the float Energized - Answer- Overhead power lines must be considered to be in this condition until electrical authorities indicate otherwise Prohibited zone - Answer- No part of the crane or load must ever enter this area around an energized power line kV - Answer- The prohibited zone must be enlarged as this increases 20 foot - Answer- What minimum distance does OSHA require be maintained when voltage up to 350 kV is unknown 50 foot - Answer- What minimum distance is required if the voltage is over 350 kV and unknown Qualified signal person - Answer- This person must be appointed any time the crane is working within a boom's length of the prohibited zone Tag lines - Answer- The use of these should be avoided when lifting near power lines, however if necessary should be non-conductive type Above power lines - Answer- Avoid operating cranes or handling materials in this area of power lines Remain in the cab - Answer- What does an operator do if the crane comes in contact with a power line
Jump - Answer- If it is necessary to leave the crane cab before power lines are de- energized after contact, how does the operator exit the cab transmission towers - Answer- A crane can also become electrically charged when working close to these (radio, microwave, cell) Manufacturer - Answer- Before traveling on site with a load, be sure that this is allowed by the Backward collapse - Answer- Ensure the boom low enough when traveling with a load to avoid the possibility of this Toward the load - Answer- Always travel in this direction when traveling with a load Boom extension, jib, or pinned section - Answer- Most manufacturers do not permit travel with a load when the boom is in these settings Raised - Answer- To prevent a lattice boom crane from tipping forward, the boom should be in this position before traveling down an incline Lowered - Answer- To prevent a lattice boom crane from tipping backwards, the boom should be in this position when traveling up an incline Controlling entity - Answer- Responsible for seeing that the ground conditions are adequate to support the equipment. Controlling entity - Answer- Responsible for informing the user and the operator of the equipment of the location of hazards beneath the equipment set-up area (such as voids, tanks, utilities) Controlling entity - Answer- Responsible for establishing a system to coordinate the operations of two cranes that operate within each other's working radius Key items of inspection - Answer- hoist rope & reeving, op aids & safety devices, cab windows/equipment, hooks & latches, fluid levels (crankcase oil, coolant, hydraulic oil, etc.), elec equipment, leveling device, control & drive mechanisms, fire extinguisher, air/hydraulic system Access to job site - Answer- firm & reasonably level surface, no buried pipes, utilities, sewers, tanks, etc. Leveling the crane - Answer- Important to accomplish when setting up a crane on a grade 1% - Answer- Load chart capacities are based on the crane being level within this percentage
two-blocking - Answer- occurs when the hook block or headache ball makes contact with sheaves at the main boom head, extension or jib tip. this can break the hoist rope and cause the hook block or ball to fall parts of line - Answer- the number of hoist ropes which appear to directly support the lower load block or overhaul ball suspended weight - Answer- weight of all devices used to lift the load combined with the actual load weight minimum parts of line required - Answer- the suspended weight divided by the safe working load (SWL) of the hoist rope determines how many of these are required to hoist the load load moment indicator - Answer- this device measures the bearing force and moment in the crane arm during operations load moment limiter - Answer- a system which aids the equipment operator by sensing (directly or indirectly) the overturning moment on the equipment, i.e., load multiplied by radius. It compares this lifting condition to the equipment's rated capacity, and when the rated capacity is reached, it shuts off power to those equipment functions which can increase the severity of loading on the equipment boom angle indicator - Answer- device which measures the angle of the boom relative to horizontal drum rotation indicator - Answer- device on a crane or hoist which indicates in which direction and at what relative speed a particular hoist drum is turning power failure - Answer- in this event, the operator should: try to lower the load to the ground, set all brakes and locking devices, and move clutches and other controls to the off or neutral position 10 BC or more - Answer- A fire extinguisher of the rating must be on the crane at all times dynamic loading - Answer- a type of loading which can be caused by wind blowing on the crane, the swinging of a load, or by raising and lowering the load, particularly with abrupt stops shock loading - Answer- can be caused by the sudden snatching of a load or the sudden release of a frozen, caught or stuck load duty cycle operations - Answer- high speed, high volume concrete placement, steel erection, or dragline, clamshell, grapple, and magnet applications
side loading - Answer- this effect on the crane can be caused by the following situations: when the crane is out of level, during a rapid swing, or if the swing break is applied suddenly, dragging or pulling loads sideways is not permitted, high winds, tilt up operations backward tipping - Answer- this situation is at most risk of happening when the angle between the load line and the boom is the same or close to the angle between the hoist line and the boom counterweight - Answer- too much of this can affect the crane's backward stability and increase the likelihood of the boom collapsing back over the crane, particularly when traveling up an incline two-blocking - Answer- This can cause the boom to be pulled backward over the crane, especially if the boom is operating at a high angle backward collapse - Answer- this can occur of the boom when tightening a load line that is connected back to the boom foot leaving crane unattended - Answer- land any load, disengage master clutch, place all control levers in neural, set all brakes and locking devices, secure the crane against accidental travel, shut off the engine are to be completed when? shift inspection - Answer- this is to be performed by a competent person each shift before the crane is used; also referred to as the pre-operational softeners - Answer- when lifting soft loads w/ a basket hitch, this should be used to prevent damage created from the pressure induced by sling angles. example: spreader beam wire rope end terminations - Answer- wire rope wedge socket, wire rope clips, eye splices, principle of leverage - Answer- for the crane to remain stable the crane's leverage on the load must be greater than the load's leverage on the crane center of gravity - Answer- the movement of the crane's this, increases the load's leverage on the crane and results in the crane's capacity being lowered carrier mounted - Answer- most of these type of cranes have their greatest capacity over the rear forward stability - Answer- the crane's ability to resist tipping forward
lattice boom cranes - Answer- the boom angle for this type of crane is the angle between the center line of the boom and the horizontal after the load is lifted next lower boom angle - Answer- when considering boom angle between chart listings, use this for those angle listed in the capacity chart jib angle offset - Answer- this is the angle of the jib, in degrees, relative to the centerline of the boom outward reach - Answer- greater degrees of jib offset provide more of this, however as the jib angle offset increases, the capacity of the jib decreases and the strength of the jib itself is less gross capacity - Answer- sometimes called rated capacities, these are listed in the capacity charts for the appropriate boom length, boom angle and radius. This is NOT the maximum net loads or objects that can be lifted capacity deductions - Answer- all load handling devices, which includes all rigging, must be considered as part of the load and what must be made from the gross or rated capacity when to deduct weight of crane's hoist rope - Answer- manufacturer specifies in the load chart that hoist rope be deducted, crane is reeved with more than the minimum parts of line required to lift the load, crane is reeved with hoist rope not being used to make the lift, there are parts of line below ground level calculating weight of hoist rope - Answer- multiply boom length by parts of line by rope weight per foot net capacity - Answer- this is the gross capacity minus weight deductions for load handling devices. this is the MAXIMUM net load or object that can be lifted gross load - Answer- net load weight + weight of attachments, lifting devices, blocks, balls, wire rope, & rigging net load - Answer- actual weight of item being lifted total load - Answer- the combined forces produced by the actual load weight, lifting attachments and movement of the load and attachments parts of line - Answer- the number of hoist ropes which appear to directly support the lower load block or overhaul ball formula for determining minimum parts of line required - Answer- weight of hook block + weight of rigging + load weight = suspended weight / SWL of hoist rope =
