Skimming Boom Design, Material Selection & Bending Moments, Agri Mech.

[FarmerBob]

I'm currently studying Agri. Mech. Eng but I need some help on this, I know roughly what to do but it's where to start:

1. Design a skimming boom for a biomass slurry transfer tank which can have a reach of 7.5m. Tool must attach to a "quick hitch" plate - factory spec for the loader is 3750Kg @ 600mm off the front of this quich hitch plate. Design to not overload the loader or have excessive deflection in the beam. Assume blade at the end of the boom no more than 100kg in weight.



2. Not sure of all the them at this stage but I'll need: mass of the boom, deflection in the boom and the applied moments to the loader I assume?



3. I think for the boom I'm going with 200 x 200 x 16 SHS at 91.5Kg/m assuming a 981N force applying at the end of the 7.5M and my calcs show a deflection of around 7mm over this length which is acceptable? But it's the weight on the loader I'm not sure about? If it's 3750 at 600mm then does it make it (3750 x 600)/7500=300kg? Also if I've the boom, blade and hitch plate (probably with strengthening webs) how do I calculate the centre of gravity?

 

[nvn]

FarmerBob: Compute the moment on the quick hitch plate due to the blade weight. Secondly, compute the moment on the quick hitch plate due to the beam self weight. Add these two results together to get the total moment.

Compute the cantilever deflection due to the blade weight. Secondly, compute the cantilever deflection due to the beam self weight. Add these two results together to get the total tip deflection. Your current deflection of 7 mm is incorrect. Try again.

By the way, always leave a space between a numeric value and its following unit symbol. E.g., 981 N, not 981N. See the international standard for writing units[/color] (ISO 31-0[/color]). Also, always use correct capitalization of unit symbols. Kg means kelvin gram, kg means kilogram. M means mega-, m means metre. See NIST[/color] for the correct spelling of any unit symbol.