A single point lift of a 3 ton load is required in order to lower the payload into a confined space. Is the chosen clevis pin adequate?

1. Heavy Lift Rigging
Safety stress analysis
4/19/2017 rev A
Don Blanchet
3B Associates
dwb3298@verizon.net

2. Goals
 Determine the max stress for critical
joints in a heavy lift rigging assembly.
 The pick is single point max load of
3 tons.
 Load and metal stress analysis using
Solidworks Simulation finite element
analysis.

3. Model
Lift load
3 tons
Lift
point

4. Model
Large clevis
Pin retained
With 3
0.75 inch
dia bolts

5. Model – 4 inch dia pin

6. Load rotates during vertical lift

7. FEA mesh
FEA No penetration surface contact
conditions pin
shaft through clearance
holes allows free rotation
Lift point
Gravity
direction

8. Stress
results
max
90,000
psi

9. Stress results pin

10. Conclusions
 The clevis pin must be made of a
material with a yield strength
>92,000psi (heat treated alloy steel)
 Local yielding of the pin will not result
in a catastrophic failure but it will
probably make disassembly extremely
difficult.