Six Sigma helps to achieve an increase in quality by eliminating defects and variation while increasing yield. Automation is not only a good way to increase production, but it helps meet the criteria of Six Sigma. One of Six Sigma’s goals is to get rid of defects, and defects are anything that could lead to customer dissatisfaction. With lean automation, productivity will increase along with customer satisfaction.
Customer satisfaction is a major goal in Six Sigma. Therefore the product that comes off the line must be free of defects. There are many ways to identify and remove product with defects. One way is to have a final inspection of the product. This method is usually done by people with instruments or other devices to help them spot the defect. This is not the best method. Even with instruments, humans make mistakes. An automated process could have inspection stations set throughout the process. This method allows the inspection to be simplified since the machine is only looking for one defect at a time. Since the inspections are placed throughout the process we can tell the machine to stop doing work on a defected part. This not only keeps the machine form doing unneeded work on a defected part, but also helps identify where in the process the defect took place.
Automation not only allows you to inspect the product throughout the process, but it allows you to get rid of some inspections. For instance, consider a cylindrical part that needs to have a feature accurately placed in the center. An inspection could be set up to measure the concentricity of the outside of the cylindrical part and the feature, or there could be a guide for the punch tooling built in such a way that it is impossible to place the feature out of the tolerance range. This is only one of many ways to eliminate an inspection.
As stated earlier, eliminating people from doing the inspection is a good way to eliminate defects from making their way to the customer. The same principal goes to the actual process of making the product. One of the steps in Six Sigma is to eliminate variation. An automated process will do just that. The machine will make the product the same every time. For instance, say that a step in a process is to place and fasten a screw in to place. A person would place the screw in and torque it down differently every time. If the screw was not torque properly the product could have a failure. With an automated process the screw would not only be torque to the right value, but verified that is was torque correctly. This is just one simple case, but it shows how an automated process would eliminate variation.
Automation and Six Sigma are a good fit. Automation helps fix the root cause of a problem, and eliminates defects and variation by simplifying the process and taking out the human errors.