Learning the Alphabet
A complete set of worksheets specifically designed to help teach each letter of the alphabet - starting from the most basic concept of the letter shape to the introduction of the most common sound.
These factors are used to calculate the actual load on each leg of the sling: Tension = (Load / Number of Legs) × Angle Factor .
Instructions on how to read boom length vs. radius.
The ground beneath the crane must withstand the massive forces exerted during a lift. Mobile cranes transfer their entire weight plus the load weight through the outrigger pads. Estimating Max Outrigger Load
Center of Gravity identified and marked on the physical load All slings, shackles, and spreader bars inspected for wear These factors are used to calculate the actual
For uniform materials (like a steel plate or concrete block): Weight = Volume × Density of the material
Miscalculating the CoG leads to tilting loads, unequal sling loading, and potential crane tipping. 3. D/d Ratios and Rated Capacity Reductions
While full standards require purchase, official committees frequently publish free safety bulletins, white papers, and introductory calculation guides. The ground beneath the crane must withstand the
When slings are used at an angle, the tension in each sling increases as the horizontal angle decreases. This is due to the introduction of horizontal vector forces. The formula to calculate the tension ( ) on an individual sling is:
When two slings meet at the hook, the tension on each leg depends on the sling angle. T = (Weight / 2) x (L / H) or T = (Weight / 2) / sin(θ) Where:
When a rope or wire rope sling bends around a curved surface (like a shackle body, pin, or crane hook), its mechanical strength decreases. This is dictated by the or crane hook)
The definitive standard for jacks, cranes, slings, and rigging hardware.
Excellent for understanding wire rope strength, safety factors, and calculations.