In this case there were several requirements that made it difficult to find an off the shelf product that would accomplish the task. The belt had to have cleats and side walls to contain the product, in this case a ceramic material being dumped into a hopper. The conveyor had to have a specific height to reach the hopper, in this case a little over 9 feet. There also had to be a short flat section at the bottom to catch the product as it was “scraped” off of a cooling table. Since I had decided to build the cooling table and cart myself I also decided to build the conveyor.
I had done a lot of controls work for Smalley Manufacturing, a Knoxville, Tennessee food service conveyor manufacturer, so I talked to them first. They had a lot of resources they use for conveyor parts and are also a reseller of components. They helped me find a belt and rollers that were appropriate for the job. I also looked on the internet and found several standard conveyor component vendors to provide items such as the shafts, bearings and other odds and ends. Many of the UHMW parts were made by a local machine shop according to our drawings. The sides and structural elements were made of tube and plate steel.
One of the things I learned during this process was the value of the proper tools. We had a mill, lathe and Ironworker, but most of our cutting and welding equipment was not up to the task. The steel plate was 10″ by 1/4″ and all we had at the time was a cutoff saw with an abrasive blade, a portaband and a bandsaw. Needless to say we spent much more time cutting steel than was economical. The steel came in from the vendor in manageable lengths but angles had to be cut, holes drilled and tube cut and welded. It was an adventurous time for me as I only had two employees at the time in addition to my wife and daughter, who helped immensely. It was also summer in Knoxville and we had to keep the back doors open to allow the metal fumes and smoke to escape. Wearing a welding jacket in 95 degree heat with 90% humidity was rough!
All in all it was a great experience and I learned a lot both about conveyors and fabrication. This experience prompted me to purchase several more important tools including a roll-in bandsaw and a better welder. Despite starting out as a purely controls oriented company I found that I enjoyed the challenges of learning new things and solving mechanical problems. This conveyor, the water cooling table and integration into the existing plant roll mill system took about 4 months from the initial purchase order until installation.
For anyone wanting further information on this application or any other I am always happy to share. There are many resources available on the web through various conveyor manufacturers. There is also a forthcoming section on the Automation Primer section of this site dedicated to conveyors and other special purpose systems such as vibratory bowls, stepfeeders, etc. Stay tuned for more!