Introduction to Rigging Engineering | PDF | Crane (Machine) - Scribd
If an object's weight isn't marked, engineers calculate it using the material's density ( ) and the object's volume ( Where to Find Free Technical PDFs rigging engineering calculations pdf free download
| Calculation | Why It Matters | |-------------|----------------| | | A 45° choke angle doubles the tension—most failures start here. | | D/d ratio (diameter of bend / rope diameter) | Bend a 1″ rope around a 4″ pin and you’ve lost 50% of its strength. | | Center of gravity (3D) | A 1% CG error on a 50‑ton load = 1,000 lbs of unexpected tilt. | | Cribbing & crush pressure | Soft ground under a steel outrigger pad is a hydraulic press in slow motion. | | Sling angle factor | 60°? 1.15× load. 30°? 2× load. That’s not a margin—it’s a multiplier of danger. | | Hook load with spreader beams | Most people over‑design beams and under‑design the top shackle. | | Wind loading on suspended loads | At 30 mph wind, a large tank becomes a sail—lifting capacity can drop 40%. | Introduction to Rigging Engineering | PDF | Crane