Automated Device for Filling Experimental Silos

Experimental Silo Packer

Project 99.07

Design Team Members:

Name / Address / Phone / E-mail
Adel Abumohor / 215 Beautree Rd. / 369-5883 /
Jeffrey Acheson / 213 Sussex Hall / 837-8824 /
Peter Sullivan / 351 Paper Mill Road / 731-1314 /
J. Michael Tate / 209 Gilbert Hall A / 837-3533 /

Sponsor:

Dr. Limin Kung / Townsend Hall / 831-2522 /


Background:

Silos have been used on farms for a long time. When people think of farms, the usual picture includes a red barn with a silo sitting next to it. Despite their place in the cultural landscape, most people still do not know what they are used for, how they work, or that research in such an old practice is still being done.

Silos are used to store grain and various other plant materials, known as “silage”, mainly for feeding the livestock on the farm. The silage is usually sprayed with some sort of bacterial agent and then sealed in a silo with as little air as possible. The bacteria the silage is sprayed with uses up what oxygen is present in the silo after sealing, creating an anaerobic storage state. Molds and other spoiling agents need this oxygen to reproduce, so without oxygen the silage does not decay and can last for prolonged periods of time as long as the silo remains sealed.

Current research being done by our customers to improve this process revolves around testing different bacterial treatments. Because conducting replicated studies with large farm silos would be impractical, research on the effects of different bacteria is done by packing small test capsules or silos that have been treated with different bacterial compounds. The test silos come in two sizes, a 5 gallon paint bucket called a macro silo, and a small PVC pipe called a micro silo. The macro silos are packed using pressure applied by a person’s foot, while the micro silos use the simple lever apparatus that was displayed at Customer Night. The silos are then opened after a given time period has passed and the contents are checked for spoilage.

Problem:

Because of the need to test different types of bacteria, there must be about 40 silos filled for each test run. Since the object is to remove the oxygen, it is beneficial to have the smallest amount of oxygen possible in the silo once it is sealed. This is done by tightly compacting the silage into the silo. The problem encountered is that the current process of packing the silos with silage is time consuming, laborious, and inconsistent. The current machine used at the research lab takes approximately four to five minutes to fill a micro silo and will not work on a macro silo. It cannot be operated by one person alone and the people who do operate it undergo considerable physical stress and discomfort. Once the silo is packed there is no way of determining the volume of silage that went into the silo. Packing results can vary greatly. An additional problem arrises if the amount of silage put into the micro silo is too small. The rubber stopper on the end of the silo may sink far into the tube and become difficult to remove. The macro silo does not use rubber stoppers so it does not have this problem. However, the packing volume of the macro silo is even less predictable than the micro silo because it is currently being compacted by pressure from a person’s foot. The silage in the macro silo is not seeing even pressure applied across the top surface and the density is not uniform throughout.

The overall goal of our project is to make the process of compacting silage into the silos more consistent, less labor intensive, and faster. The volume of silage put into the silo will be known and will be approximately the same for each micro or macro silo. Hopefully this will aid the research in that they will have more accurate control silos and more reliable data. The second benefit of our solution will be reduced manpower. We hope to cut the number of operators down to one person. This will free up people in the lab to carry out other duties. The work that the operator has to do will be less physically strenuous and therefore more comfortable over an extended period of time. We will cut down on the time needed to fill one silo so the researchers can move on the other work sooner.


Methods:

Mission:

The purpose of our team is to design and build a means to quickly and reproducibly load a test silo without requiring extensive manpower.

Wants:

Name / Organization / Rank / 1st Want / 2nd Want / 3rd Want / 4th Want / 5th Want
Limin Kung / UD Ag Department / 1 / Not Physically Demanding / Reproducible results / Fast Operation / Simple Operation / Low Cost
Navin Ranjit / UD Ag Department / 2 / Reproducible Results / Not Physically Demanding / Safety / Easy to Clean / Easily Transportable
Richard Morris / UD Ag Farmer / 3 / Takes up little Space / Easily Transportable
Martin Stokes / U of Maine / 4 / Automatic/ Pneumatic / Reproducible results / Variable Silo Size / Iterative Process
Joseph Harrison / Washington State U / 5 / Not Physically Demanding / Reproducible results / Fast Operation / Simple Operation / Low Cost
Chris Rode / Chr.Hansen Biosystems / 6 / Reproducible Results / Easy to Clean
Carol Meyers / Kemin Industries / 7 / Reproducible Results / Easy to Clean
Final Ranking / Want Description / Rate of Importance
1 / Reproducible Results / 0.295
2 / Not Physically Demanding / 0.288
3 / Fast Operation / 0.083
4 / Safe / 0.028
5 / Low Cost / 0.028
6 / Easily Transportable / 0.025
7 / Takes Up Little Space / 0.023
8 / Automatic/Pneumatic / 0.023
9 / Variable Silo Size / 0.008
10 / Simple Operation / 0.006


Constraints:

1)  The design must be able pass through a normal doorway.

2)  The design must be able to be moved by two people.

3)  The design must pack a silo as fast as current methods.

4)  The design must not recess the stopper on the micro silos more than a centimeter.

5)  The design should not cost more than $500 to build.

Benchmarking:

Competitor /
Rank
/ Strength
Stokes Pneumatic Loader / 1 / Good Stroke Length, Reproducible, Automatic
Stokes Front End Loader / 2 / Powerful, Cheap
Pack-Master Trash Compactors / 3 / Quick, Powerful, Manual or Automatic
Hydro-Press Trash Compactor / 4 / Powerful, Good Stroke Length
Dillon's Shotshell Loader / 5 / Feed bin, reproducible
Burnt Mill Shell Loader / 6 / Feed bin, reproducible, precision
Torpac Capsule Filling Machine / 7 / Precision, reproducible, gang operations
KR Komarek Briquetters / 8 / Great feed mechanism, Powerful
Soda Can Crusher / 9 / Low Cost, Simple design
Shin I Inclinable Power Press / 10 / Powerful, quick
Chen-Li Precision Press / 11 / Powerful, Precise
Fair Oaks Drop Forging Press / 12 / Powerful, Precise


Scheduling:

Estimated Budget: $500


Ground Rules:

1)  All members of the team are responsible for its progress, do not single out individuals for blame.

2)  Attend to all team meetings, be on time and prepared.

3)  Complete assignments on schedule, but if you realize that this is not possible inform the rest of the team immediately.

4)  Be respectful toward all team members, even if they are not present. Know your fellow members’ strengths and weaknesses, be patient and trust them to accomplish their objectives.

5)  Be positive, criticize constructively not destructively.

6)  Deal with disagreements within in the team objectively, do not get too attached to your own ideas and do not take personal offense at criticism.

7)  Be focused, avoid disrupting the team and try to communicate clearly at all times.

8)  Ask questions if something isn’t fully understood, but realize time constraints may prevent a complete explanation.

9)  Encourage other members of the team, but make sure this encouragement is genuine.

10) Make informed decisions, no decision is almost always preferable to a bad one.

11) The code of conduct can be flexible, do not become obsessed with following it if something unforeseen occurs. The code of conduct may be changed to deal with situations that arise as the team develops.

12) Do not lose faith, try to avoid frustration, and try to have fun!