Sometimes I wish for an engineer

[ptonsparky]

Doing a small grain mill system for grinding corn. Eventually eight motors total. I supplied a 60 hp for the mill. It can handle up to 100. Milwrights supplied and designed the rest. Mill would shear bolts because the take away augers couldn’t keep up. After several attempts they decide the best solution would be to cut the flow of corn into the mill. Figured that would happen. I had the pleasure of telling them today that they solved the shear pin problem by cutting production about 30%, but the feed and takeaway augers are overloaded. Each need a bump up in HP. That’s two of three they supplied that we’ve even started. Frustrating.

 

[gadfly56]

Doing a small grain mill system for grinding corn. Eventually eight motors total. I supplied a 60 hp for the mill. It can handle up to 100. Milwrights supplied and designed the rest. Mill would shear bolts because the take away augers couldn’t keep up. After several attempts they decide the best solution would be to cut the flow of corn into the mill. Figured that would happen. I had the pleasure of telling them today that they solved the shear pin problem by cutting production about 30%, but the feed and takeaway augers are overloaded. Each need a bump up in HP. That’s two of three they supplied that we’ve even started. Frustrating.

Sometimes it isn't necessarily an engineer you need, it's a sharp project manager. Well, that could be an engineer also, but I don't know that anything involved in this lash-up needed engineering, per se. Just flow in, flow out, what material handling equipment will make that happen.

 

[__dan]

If you want to spend time diving deeper into it, I would probably be looking for an equipment rep who really knows his stuff, to talk to. There is someone who has seen the application and its many various problems, many times.

If the take away augers can be increased in size or number to match the production capacity of the mill, that should be a set of numbers obtainable at the design stage or prior to implementation. Mill manufacturer or the equipment rep is who I would be looking to for guidance about the matching equipment package, including their experience in what works and what does not.

The mill would also have to handle starting and stopping loads. So you probably have to measure a hopper fill level at the mill or feeding into it, and control the feeding augers to maintain optimum hopper level.

Before I proceeded with my guesses too far, I would also guess that this is a standard problem that has been seen and solved many times prior. So I would be looking among the existing successful solutions for ideas about how to proceed.

 

[kwired]

If you want to spend time diving deeper into it, I would probably be looking for an equipment rep who really knows his stuff, to talk to. There is someone who has seen the application and its many various problems, many times.

If the take away augers can be increased in size or number to match the production capacity of the mill, that should be a set of numbers obtainable at the design stage or prior to implementation. Mill manufacturer or the equipment rep is who I would be looking to for guidance about the matching equipment package, including their experience in what works and what does not.

The mill would also have to handle starting and stopping loads. So you probably have to measure a hopper fill level at the mill or feeding into it, and control the feeding augers to maintain optimum hopper level.

Before I proceeded with my guesses too far, I would also guess that this is a standard problem that has been seen and solved many times prior. So I would be looking among the existing successful solutions for ideas about how to proceed.

I've seen mills where the supply bin is above the mill and mill input rate is controlled by how far a gate is opened.

 

[electrofelon]

Replace that shear pin with a grade 8 bolt will solve your problem

 

[drcampbell]

Replace that shear pin with a grade-8 bolt will solve your problem

Why not? After all, millwrights and mechanical engineers solve problems by installing heavy-duty fuses.


In all seriousness, this is yet another desperate cry for switching to the SI (metric) system of weights and measures.
When it's unnecessary to convert units, answering questions like this will be simple -- maybe even obvious.

Full disclosure: I am an engineer.

 

[ptonsparky]

Replace that shear pin with a grade 8 bolt will solve your problem

Being a couple electricians, we discussed it.










With a chuckle.

 

[kwired]

Replace that shear pin with a grade 8 bolt will solve your problem

Sometimes the damage is already done if it shearing the pin and you will just expose it faster by using the grade 8 bolt.

Was working at a farmer's site while he was harvesting earlier this year. He had a 100 foot tractor PTO driven auger used to fill his bins. He had been occasionally replacing shear pin on input shaft and was replacing with the proper shear pin. Well it went again while I was there, he replaced it, tried starting it up easy assuming it was plugged, cleared bunch of corn out, still troubles, eventually tore auger apart and found auger flighting separating from the shaft.

Don't know what happened in the end, he had an auger at another site he towed to this site to use, but he said couple years ago it did same thing and they sold him new improved auger flighting that wasn't supposed to do that for whatever that is worth.

 

[ptonsparky]

Had a customer replace the shear pin with a #2 Phillips screwdriver. About $500 for the next weakest link, plus my time.