Will my steel ejection mold bolts shear under sideways load?

AI Thread Summary
The discussion centers on concerns regarding the shear strength of bolts in a steel ejection mold's bridge mount when subjected to sideways loads during lifting or flipping. The mold weighs 5,900 lbs and uses four 5/8" diameter bolts with specific dimensions and thread engagement. A safety issue is highlighted due to the independent nature of the cylindrical steel pillars, which can increase bolt tension significantly during lifting. Expert advice suggests consulting a qualified Mechanical Engineer to assess the design and potentially implement structural reinforcements like diagonal braces. Ensuring the bolts can withstand the load is crucial for safety.
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.
 

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