What are the critical dimensions?
|
Generally these 4 "golden"
numbers:
Weight, Away, Up, In |
• Weight of heaviest object
• Height of building - distance
up
• Crane distance away
from building
• Distance in
from edge of building |
1 - Consider the object(s) to be lifted
|
| Need the size and accurate weight of object(s) to be lifted |
• The manufacturer's cut-sheets can help here.
• Be sure to include rigging in the weight calculations.
• Remember "seasonal" weight such as snow, mud etc.
• If removing an older unit, what is the weight of that unit
• Can the load be divided into smaller parts to reduce weight? |
| How many items are being lifted? |
• Where are they located on the roof/site?
• Can the crane set them all from one location, or does it need to
be re-located? |
| Does it need any special rigging? |
• Are spreader beams needed?
• Other items like chain-falls, shackles etc. |
| How will the items get there? |
• Are they on-site, delivered by truck etc. |
2 - Look at the jobsite (building/structure)
|
| Accurate Height of building (tower, platform etc) |
• Distance from ground to highest point
• First wall (object) the crane will encounter
• Platform or support the object will go on |
| Is there anything the crane/load has to clear |
• Other sections of the structure
• Fencing or enclosures
• Other rooftop structures or equipment
• Light poles or wiring
• Trees |
| Are there any overhead obstructions? |
• Overhead wires or cables
• Canopy or Ceiling (if inside)
• Trees |
| Are there underground structures? |
• Soft Ground
• Sprinklers
• Septic systems
• Wiring
• Sewers or piping
• Electrical utilities
• Tanks or Vaults
• Hollow Tunnels
• Fresh excavations
• Basement walls within 10' of crane |
| Is this a "Critical Lift"? |
• As defined by General Contractor
• Over 85% of rated crane capacity
• Near power lines or obstructions
• Using a man-cage or lift |
3 - Where can the crane locate?
|
| How
close can the crane get to the building (structure) |
• Measure distance from the building to the closest
point of the crane |
| Are there any nearby obstructions? |
• Trees, wires, cables, underground structures that
interfere with operation. |
| Is there space to set the outriggers? |
• Is the ground level?
• Is there space for the outrigger cribbing?
• Is there space for the delivery/counterweight trucks? |
| Is there space to set up the jib (if needed) and
raise the boom? |
|
| Is there enough space to swing the counterweight? |
|
| Is there enough space to swing the load? |
|
| Are you on a street/alley? |
• Are there cars parked that need to be moved?
• Is there room enough for the crane & delivery trucks?
• Are special city permits needed?
• Are signs and flagmen needed for traffic control? |
Is the site near an airport?
|
• If within 3 miles of a major airport check if an
FAA permit is required. |
| Are there specific jobsite requirements? |
• Start time?
• Noise ordinances?
• Specific Safety requirements?
• Other businesses that will be impacted?
• Rooms under the swing area that need to be vacated?
• Other contractors involved in this lift? |
4 - Can the crane get to the jobsite area?
|
| Look at the approach path the crane and trucks have
to drive over to get to the site |
• Are the streets wide enough?
• Are the turns wide enough?
• Are there any bridges/openings that it must fit through?
• Will it drive over any underground structures?
• Can the ground support the weight of the equipment? |
| Where will the support trucks locate? |
• Where will the setup/delivery trucks stage?
• Can they stay on-site or relocate nearby? |
| Time restrictions on travel? |
• Are there IDOT/City restrictions that limit the
movement of the cranes/trucks?
• Do you want the equipment onsite the day before the lift for an
early start? |
