Hello All,
I recently was given the task of making a model of a crane that was designed on an old hard to read drawing around 45 years ago. It oddly never had the tonnage rating on the drawing called out. Its basically a wall crane that cantilevers out. It has rollers on shafts to ride the framing of shop at 3 locations. I don't have a snip of my assembly drawing on hand showing the rollers and assembled tie rods, etc. I was fiddling with my Simulation package to see for kicks what the software would come up with for the max stress points using a specified downward force of the end of boom. We are having the drawing analyzed by a structural engineer for a tonnage capacity rating but it would be nice to get this model to give some sort of result. To avoid an assembly study with component contacts, etc., I figured a run using only my weldment with all parts globally bonded may be easier to get some kind of numbers for comparison. I used "exclude from analysis" for alot of parts in this weldment that should have no bearing structurally, plus the tie rods that are welded and get attached to a turnbuckle and another tie rod in assembly. I treated all structural members as solids and used fixtures at the 6 hole locations in channels where the shafts and rollers in my assembly would go to be fixed to roll on shop beams, then applied a 4000# (2 ton) arbitrary force at end. Long story short, the study keeps crashing. I got thru the meshing, but the sim run keeps saying that the model is unstable which I know is a common problem. I tried both bonded, no penetration and allow penetration for component contact with no luck (was hoping to not have to create contacts at each mating solid as there are alot). Also tried using soft springs to allow stability as well as large displacement. See snips below. I've attached my zip file. Just curious how to get this model to work for simulation. I'm still on SW15 by the way so if anything is sent over newer, I wouldn't be able to open it. Any comments are appreciated. Thanks.