Will my steel ejection mold bolts shear under sideways load?

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SUMMARY

The discussion centers on the structural integrity of steel ejection mold bolts under sideways load during lifting or flipping. The mold weighs 5,900 lbs and utilizes four 5/8" diameter bolts with a total length of 10.5" and a thread engagement of 1.125". Concerns were raised about the potential for bolt shear due to the independent nature of cylindrical steel pillars, which can amplify bolt tension. A recommendation was made for a competent Mechanical Engineer to assess the design and consider implementing diagonal bracing or a unifying plate.

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jessemk
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hello.
I have a ejection mold (steel) which has a bridge like mount which locates the handling eye bolts outward around hydraulic cylinders. I need to make sure the bolts in the bridge will not shear due to the sideways load when the mold is lifted or flipped 90degrees. Here is the known information:
mold weight: 5,900 lbs
Bolt Dia: 5/8"
Bolt total length: 10.5"
Bolt thread engagement: 1.125"
Number of bolts in bridge 4

Color representation:
blue:Injection mold
orange: cylindrical steel pillars with a clearance hole through
purple: eye bolt mounting plate
Red:Bolt-socket head cap screw
upload_2015-9-18_12-20-18.png
 

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jessemk said:
hello.
I have a ejection mold (steel) which has a bridge like mount which locates the handling eye bolts outward around hydraulic cylinders. I need to make sure the bolts in the bridge will not shear due to the sideways load when the mold is lifted or flipped 90degrees. Here is the known information:
mold weight: 5,900 lbs
Bolt Dia: 5/8"
Bolt total length: 10.5"
Bolt thread engagement: 1.125"
Number of bolts in bridge 4

Color representation:
blue:Injection mold
orange: cylindrical steel pillars with a clearance hole through
purple: eye bolt mounting plate
Red:Bolt-socket head cap screw
View attachment 88827

Welcome to the PF.

What is your mechanical design background?
 
There is a very real safety issue with this design.
Because the cylindrical steel pillars are independent of each other they will greatly multiply the bolt tension at the start of the lift.
That multiplication factor will be something like their length divided by the difference between the pillar radius and the bolt hole radius. Factor = Lengthpillar * ( Rpillar - Rhole )

To eliminate the problem, a competent Mechanical Engineer, (with an insurance policy), would need to review the situation and possibly design something like a diagonal brace or a plate to unify the pillars.
 
Thank you, Baluncore.

And with that advice, this thread is closed.