This an example of the type of plastic injection machines that we saw at Royal Plastic. Royal Plastic has been producing plastic injected parts for approximately ten years. Royal Plastic provides parts for six groups of consumers. The automotive parts are supplied to Prince and Jentex. Lawn and garden supplies are for H.G. Hudson. Furniture part, such as the back of the chairs, is produced for Keyworth and Herman Miller. Refrigerator parts are for Frigedar. The last category is vacuum cleaner parts for Bissell.
The injection mold machines that we saw were designed for automatic control. There were other machines that needed minimal operator interface. The primary goal of the engineer at Royal Plastic is to design the machines and dies for simplicity. Once the process is set the machines are stable to be able to continue making good parts. Royal Plastic is QS 9000 compliant. Which means, if they were to undergo the certification process that they would pass.
Something that I really enjoyed was the touchable atmosphere. The class was allowed to go up and touch the parts as they were being produced, to go up and talk to the operators. If some maintenance was going on I would have liked to ask questions about stress verses keeping the machines to full capacity.
I would have expected the off-line assembly to be more involved. There was only one section that had an indexing assembly operation. The other part of the off-line area was the printing section. The heat printing is more reliable and easier to use than the standard pad printing process. The rejects from the printing processes are thrown away. Even though normal regrind is returned in the operation the ink is a contaminant. The moisture in the air can also be a contaminant if the plastic is a hydroscopic material. Royal Plastic use heaters to dry the plastic before it can be used.