February 13th was my first day at Microtech Southwest, the plastic injection molding facility where I am doing my project. The first week was all about getting to know all the parts of the fabrication process, as well as familiarizing myself with the various tasks and duties that needed to sustain production. I spent most of my time the first week in the quality lab, where finished parts are sorted, measured, tested, and verified to ensure that each batch of battery seals confirms to all required standards. from each batch of battery seals produced, one seal from each mold is taken out. That set of seals is measured for height, width, hub height, hub depth, and potentially other factors, depending on the model of the seal. One set of seals is also put through a burst tester, to see test the pressure tolerance of the seals. In a battery, the aqueous compound inside the cell can expand with use, and if the seal is breathable enough to maintain equilibrium inside the cell while allowing enough air through so that the cell doesn't explode, then it is perfect. The burst tester applies air pressure to the seals to see if they will fail under the similar conditions, and the data from the burst machine is yet another part of the quality assurance process. The last step of the quality assurance process is the statistical analysis of the data received from all the measurement machines. If the data is within an acceptable margin of error, the seals from that batch are accepted and can then be shipped off to the battery companies where the seals are then used to build batteries.
I also spent some time getting to know the other parts of the factory, mainly one of the vision systems. The vision system is a computer with several cameras connected to it. There is also a belt on which parts are fitted on by a machine, and the parts are passed through the cameras to measure similar values such as height, width, circumference, etc. The computer then processes the data from the cameras, and if the measured values are unacceptable the parts are knocked off the belt into a scrap pile. This machine operates at an extremely fast pace, with the ability to process up to 2000 parts per minute. This means that maintenance of the machine is of utmost importance because one error can cause hundreds of parts to be incorrectly sorted, which could mean that many good parts are rejected, wasting materials or that many bad parts are accepted, destroying the established quality standards.
Recently, I have been away travelling, and due to the lack of stable internet access I haven't been able to post anything for the past couple weeks. During this temporary break from my time at Microtech, I have been doing some background research on both the plastic injection molding process and on the industrial statistical process, using materials borrowed from Mr. Clark, the director of Engineering at Microtech. I will follow up with a reflection on my findings in another post within the next week.
This sounds like really cool stuff! The quality lab and burst testing the seals sounds extremely interesting. I think I understand what the quality lab and vision systems are used for, but could you please elaborate a little on how the eDart system you mentioned works and how it links back to this? Thanks!
ReplyDeleteThe quality lab and vision system both fall under the part of the production process that involves produced seals, and are primarily involved with using statistics to test whether or not the seals that have already been produced are acceptable. The data from the eDart pertains to the injection molding machine's productive output and efficiency, and the methods used to analyze the eDart data are similar to the methods used to behaviorally analyze functions in calculus (integrals, derivatives, etc.). Basically the eDart system pertains to a different part of the production process than the quality assurance testing and Vision system, and during my first week my objective was to get a better understanding of the production process and to familiarize myself with the ways in which the parts are processed, handled, and tested before being shipped out. I will probably get more into the specific usage of the eDart system as well as the engineering aspect of the process when I return to my project later this month.
ReplyDeleteSounds awesome! I know the Baja team I'm working with uses injection molding on occasion, especially to reduce weight. It's a crucial method of engineering manufacturing! On a personal note, since you were originally going to do Baja with me, are you glad you switched over? Good luck, and I look forward to hearing more!
ReplyDeleteI don't think I can necessarily say that I am happier, since I never actually started the Baja project. However, I still think I made the right choice in deciding which better suited what I was looking for, since I was looking to find a project in a more professional setting rather than an academic one.
DeleteThis is really interesting! The vision system really caught my eye. Is it used to measure the parts that are used to make the batteries?
ReplyDeleteYes, the vision system is one of the key parts in ensuring that the battery seals conform to the desired dimensions. At Microtech, the battery seals are made and shipped off to the client companies (Duracell, Rayovac, etc.) where the batteries themselves are produced.
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