You have applied a synthetic boundary condition directly to the subject part. This will always give bad results near the condition.
Attached is the first chapter of Solidworks Simulation for Real Machines, which covers bolted boundaries. The second study in the book looks at something even more like your bracket (which is also missing the weld beads).
More on the whole work can be found at stonelakeanalytics.com. It covers a lot of practical issues that will never be found in a manual.
I knocked up a similar geometry and set it up two ways. The load is input through a loose solid pin in both cases.
Peak results near bolt holes will be very sensitive to the setup. If there really are sharp corners bearing on other solids the theoretical peak stress prediction is unbounded.
Bolted to a solid block with bolt connectors, with pre-load (over 1900 lbf in each 1/2" screw):
Resting on the same solid block with the bolts as joined solids, no pre-load:
Result with pre-loaded bolt connectors:
Result with joined solid 'bolts', all bodies in surface-surface no-penetration contact:
Shawn Mahaney has shown you some extremely good insight. I might add a couple more. When you use bolted connectors SWX has difficulty predicting stress w/in one diameter of any bolted joint so usually it is best to ignore that if it isn't too unrealistic. That you can figure out with hand calculations to get a ballpark feel for what should be expected. Another is your actual loading condition. If you have not split the surface on both the pin and yoke portions and set non-penetration conditions you will see unnatural 'sticking' which may hide some deficiencies. Third, whenever you are w/in 1 inch of a weld (the HAZ) you must reconsider the strength of your material especially in view of safety factors. Get yourself a copy of the ADM to see how much you should knock-down your acceptable stress limits to even get a simple 3:1 SF. 12,000 PSI is very likely failure of the joint if memory serves me correctly.
Shawn Mahaneyhas shown you some extremely good insight. I might add a couple more. When you use bolted connectors SWX has difficulty predicting stress w/in one diameter of any bolted joint so usually it is best to ignore that if it isn't too unrealistic. That you can figure out with hand calculations to get a ballpark feel for what should be expected. Another is your actual loading condition. If you have not split the surface on both the pin and yoke portions and set non-penetration conditions you will see unnatural 'sticking' which may hide some deficiencies. Third, whenever you are w/in 1 inch of a weld (the HAZ) you must reconsider the strength of your material especially in view of safety factors. Get yourself a copy of the ADM to see how epayitonlinemuch you should knock-down your acceptable stress limits to even get a simple 3:1 SF. 12,000 PSI is very likely failure of the joint if memory serves me correctly.
More material? Stronger material?
aluminum: 6005A T6
You have applied a synthetic boundary condition directly to the subject part. This will always give bad results near the condition.
Attached is the first chapter of Solidworks Simulation for Real Machines, which covers bolted boundaries. The second study in the book looks at something even more like your bracket (which is also missing the weld beads).
More on the whole work can be found at stonelakeanalytics.com. It covers a lot of practical issues that will never be found in a manual.
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thank you, it was very interesting for me.
I knocked up a similar geometry and set it up two ways. The load is input through a loose solid pin in both cases.
Peak results near bolt holes will be very sensitive to the setup. If there really are sharp corners bearing on other solids the theoretical peak stress prediction is unbounded.
Bolted to a solid block with bolt connectors, with pre-load (over 1900 lbf in each 1/2" screw):
Resting on the same solid block with the bolts as joined solids, no pre-load:
Result with pre-loaded bolt connectors:
Result with joined solid 'bolts', all bodies in surface-surface no-penetration contact:
i did the same with a virtual wall.
thank you !
Shawn Mahaney has shown you some extremely good insight. I might add a couple more. When you use bolted connectors SWX has difficulty predicting stress w/in one diameter of any bolted joint so usually it is best to ignore that if it isn't too unrealistic. That you can figure out with hand calculations to get a ballpark feel for what should be expected. Another is your actual loading condition. If you have not split the surface on both the pin and yoke portions and set non-penetration conditions you will see unnatural 'sticking' which may hide some deficiencies. Third, whenever you are w/in 1 inch of a weld (the HAZ) you must reconsider the strength of your material especially in view of safety factors. Get yourself a copy of the ADM to see how much you should knock-down your acceptable stress limits to even get a simple 3:1 SF. 12,000 PSI is very likely failure of the joint if memory serves me correctly.
Thanks for the step by step direction