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A comprehensive overview of key concepts and principles related to crane operation, focusing on safety procedures, equipment maintenance, and operational best practices. It includes a series of questions and answers covering various aspects of crane operation, such as load capacity, boom angles, and safety protocols. This resource is valuable for individuals preparing for the nccco core exam or seeking to enhance their understanding of crane operation.
Typology: Exams
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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
carpenter's level - Answer-Use this tool placed under or close to the boom foot for an accurate measure of level 90 degrees - Answer-Swing the boom to this degree over the side and check for level again Center of gravity - Answer-the point where the entire weight of a body can be considered concentrated so that, if supported at this point, the body would remain in equilibrium in any position tape measure - Answer-use this tool to accurately verify the radius wires, strands, core - Answer-the three basic components of wire rope strands - Answer-the first number of wire rope classification that indicates how many of these which make up the rope wires - Answer-the second number of wire rope classification that indicates how many of these which make up a strand mechanical advantage - Answer-this is the leverage gained by reeving a traveling block with multiple parts of hoist line line pull - Answer-this is equal to the load weight plus any force required to overcome block friction total load - Answer-this is determined by multiplying the proper angle factor by the load weight plus the force required to overcome sheave friction Rigid, spreader - Answer-two of the most common types of lifting beams used
5:1 - Answer-the design factor for suspended personnel platforms must be this water - Answer-Include the weight of this when lifting a load from a barge or platform submerged under water tag line - Answer-Use of this is not necessary for each lift, but when it is required to control a load, make sure that it has sufficient strength, no knots and is long enough to keep personnel from under the load two-blocking - Answer-this can occur if the boom is lowered with the block or ball is too close to the boom head or other hoisting points such as the boom extension or jib tip anti-two-block device - Answer-this device can stop an impending two-block condition and, if necessary, prevent further hoisting, boom extension and lowering of the boom 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 backward stability - Answer-the crane's ability to resist overturning backwards while in an unloaded condition overloading the crane - Answer-tipping or overturning and structural failure are caused by capacities or rated loads - Answer-these are based on either stability or non-stability limiting factors such as structural, mechanical, hydraulic, pneumatic, etc. lifting capacity - Answer-parts of line, net capacity, capacity deductions, gross capacity, boom angle, load radius, boom length, areas of operation, and configuration are required to determine this selecting correct capacity chart - Answer-this will be determined by how the outriggers, stabilizers or crawlers are configured/used on the crane mounting over side, rear, front - Answer-typical work area quadrants of a crane's working circle weaker quadrant - Answer-when picking a load from the front and placing it in the side quadrant, always use the load chart that governs which quadrant? carrier-mounted crane - Answer-for improved front stability, this type of crane is equipped with a front stabilizer (or jack)
center-mounted crawler cranes - Answer-there are two types of work areas for this type of crane: those based on the center of rotation of the Upperworks and those based on the center line of the tracks jib length - Answer-this boom extension is not normally included in the term "boom length" lower capacity - Answer-when considering boom length between chart listings, always use this of next longer or shorter boom length. never split the difference load radius - Answer-the horizontal distance from the center of rotation to the center line of the hook or center of gravity of the load when lifted gross capacity - Answer-unless directed by the manufacturer, use the load radius rather than boom angle when determining this next longer radius - Answer-when considering load radius between chart listings, use this when the load radius is between the radii listed in the capacity chart boom angle - Answer-on telescoping boom cranes, this is the angle between the bottom of the base boom and the horizontal after the load is lifted 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 =