To properly size and select a crane for a job many factors must be considered to determine the right type of crane and corresponding capacity.
Should it be a heavy lift crane? Boom truck crane? Rough Terrain crane? Weight and size of load, location, reach, obstructions, and other factors must be determined before choosing crane.
Here are some key steps:
Calculate the maximum radius from the center of pin.
Confirm the total weight of the load. If not known, consider consulting an engineering professional.
Determine clearance issues, either height under ceiling or overhead obstructions.
Allow for the height of obstructions between crane and load.
Consider the hook height required with lifting equipment.
Allow for the distance from jib head to the hook.
Determine if obstructions will impede the counterweight when swinging.
Verify if the crane will need to work around obstructions during set up.
Discern whether specialized rigging equipment will be needed to avoid removing critical plant equipment during the lift.
Consider what boom length will be required.
Ensure whether the ground can support the crane. Further testing may be needed.
Establish how the crane will access and leave the site. Are roads and entrances able to accommodate?
All these factors are essential to the process of selecting a crane for a safe and successful job. SOURCE: Barnhart
For further Guidance, check out a copy of the Article below, which I wrote back in August 1993, but which principles still apply today.
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