Jun 25
StevenDeamUncategorized
The sixth waste that we will examine is that of over-processing. The definition of over-processing is to do more work on a piece than is required by the customer. In the simplest explanation this is simply anything done to the part that does not add value to the product. A good – and controversial – example of over-processing a part is inspection.
Pretty much everyone would agree (I assume) that inspection is a necessary part of the process of precision manufacturing. When it comes to precision aerospace parts, it is difficult to imagine shipping parts without a full detailed inspection. The consequence of a defective part could be catastrophic – so we inspect everything. However in the process of inspection, assuming that the part is manufactured properly and passes inspection, nothing is done to increase the value to the customer. The part is exactly the same after inspection as it was before.
There are many other ways to over-process a precision machined part. Using tools that are more expensive than necessary, running machines too slow, over-engineering the fixtures, holding a tolerance beyond what is necessary for function, or a number of other problems. Of all of the wastes, I think that over-processing may be the most difficult to eliminate, or even identify at times.
The approach that we take at CNC Industries to eliminate over-processing starts before we run the first part of the first batch that we produce. Before any new part is produced, we conduct a ‘pre-flight meeting’ in which we examine all aspects of the part. We will look into all of the common areas of over-processing and ensure that steps are taken to prevent over-processing. Once a consensus process is established and reviewed to ensure that it will be ‘lean’ enough, we enter the router information into Job Manager 2, our ERP system. At this time the process established will be on record for each involved party – from purchasing to final shipping, all processes have been reviewed to eliminate over-processing, as well as the other wastes.
With our electronic information system we are able to continually review the established processes quickly and thoroughly. Every employee in the company is also able to suggest improvements – which has many times lead to a reduction of waste – often through elimination of over-processing. With over-processing waste it is critical to constantly be looking for a better way to produce the parts. The effects of over-processing can be very expensive, but it is often hard to detect.
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CNC Industries is a Fort Wayne, Indiana based machine shop specializing in precision CNC machining, fabrication and assembly of application-critical and custom machined parts for the Aerospace, Defense, Medical, Industrial and Transportation markets. The company presently employs approximately 55 people.
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Jun 18
StevenDeamAerospace Machining, Certification, Document Management, Lean Manufacturing, Precision Machining Aerospace Machining, Custom Machined Parts, ERP, Job Manager, Lean Manufacturing, wastes
The fifth of the seven wastes is the most readily obvious waste – defects. A part or product that is not made correctly and needs to be either re-worked or discarded, is obviously a waste. The time spent on the original part is wasted, the material and other costs are wasted, the time that it takes to re-work or re-make the part is wasted. Overall defects cause considerable disruptions and waste.
Once again high volume work has an easier time of removing defects from the process. the length of the run of a part will justify creating more complex and expensive fixturing to enable quality at the course – so that the part has little or no chance of being produced improperly. Custom inspection procedures will allow quick discovery of any non-conforming parts as well.
In a low volume high mix facility – as a large portion of CNC Industries is, making custom machined parts and precision aerospace machined parts, we cannot spend an extensive amount of time on fixturing – our lead time for the entire first batch of product is sometimes shorter than production companies will spend on a single fixture for a production part. The inspection requirements and quality standards will also vary – sometimes greatly – between parts running through our shop at the same time. We have to ensure that each fixture is made quickly and still performs as it needs to.
Of course defects are caused by a myriad of issues beyond just the fixturing the part correctly. We have many more methods of preventing mistakes and defects before they occur, but I think a more telling evaluation of a companies dedication to eliminating defects is the processes taken when a defect does occur. At CNC Industries, we place great emphasis on root cause analysis and corrective / preventative actions. As we are nearing our AS9100 certification, we are more aware of this need than ever before.
Our Corrective Action System is based on the Apollo Root Cause Analysis and allows and indefinite depth of root cause analysis. We regard and defect as a serious issue and are quick to come to an understanding of the root cause that allowed the defect to occur. With our ERP system, we are able to quickly resolve any ongoing systemic issue and immediately take the necessary corrective action to prevent future occurrences of the issue. Preventative and corrective actions and their resolutions are transmitted throughout the company immediately upon completion and necessary procedural and process changes are automatically updated. All relevant documentation is kept entirely in sync with our digital paperless document system.
The ability to adjust our entire process to address a deficiency in the processes that we utilize allows us to have an extremely low defect rate – and when the very occasional defect does occur we can quickly adapt and prevent the problem in the future.
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CNC Industries is a Fort Wayne, Indiana based machine shop specializing in precision CNC machining, fabrication and assembly of application-critical and custom machined parts for the Aerospace, Defense, Medical, Industrial and Transportation markets. The company presently employs approximately 55 people.
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Jun 14
StevenDeamAerospace Machining, Document Management, Lean Manufacturing, Precision Machining, Technology Aerospace Machining, Custom Machined Parts, Document Management, Lean Manufacturing, motion, the seven wastes
The 4th waste identified in lean manufacturing is Motion. Motion concerns the ergonomics of the workers in a process and any unnecessary steps or movement that they have in the process.
To again look at the difference of a high mix / low volume precision aerospace machining facility and a high volume production we will see a difference in the ability to reduce motion. In a high volume production environment you can count on a particular workstation being focused on a single task – even if that task is performed over a variety of individual parts, the motions and the ergonomics will be similar. In a low volume precision machine shop, the task on one day may be entirely different than the task of the prior day. While they will be related still – depending on the functionality of the machine at the workstation – the individual parts may require a significant difference in motion or handling.
To compensate for this changing process, CNC industries has designed it’s facility to accommodate a high mix of precision parts easily. While the information and documentation may vary from one part to another, we have standardized the method of getting that information into electronic information stations which are uniformly located near the workstations. Each worker in our facility may count on being able to get all necessary work instructions in the same way.
We have also standardized our machine setups with the tooling being handle off of the machine to eliminate unnecessary motion in the setup process. The advantages of removing extra motion include more productivity, less stress on the people involved in the process, as well as lowered chances of errors and mistakes being made. So even with a facility dedicated to fully custom machined parts and prototypes, we can easily remove unnecessary wastes.
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CNC Industries is a Fort Wayne, Indiana based machine shop specializing in precision CNC machining, fabrication and assembly of application-critical and custom machined parts for the Aerospace, Defense, Medical, Industrial and Transportation markets. The company presently employs approximately 55 people.
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Jun 07
StevenDeamAerospace Machining, Lean Manufacturing, Precision Machining, Technology Aerospace Machining, Custom Machined Parts, inventory, Lean Manufacturing, Precision Machining, the seven wastes
In continuing on the Lean Journey, we will talk about the third of seven wastes: Inventory. Historically, inventory was not considered a waste. Large batch manufacturing was a necessity at the beginning of modern machining and manufacturing. Inventory stocks were considered healthy as they indicated that a business could ship to their customers quickly. The story of Inventory becoming considered a waste starts in post WWII Japan. Japan underwent a transformation in their productivity and processes after WWII and began to compete well on the world market. Unfortunately Japan does not have the land area that America does, and therefore the cost of holding inventory was much greater – due to the higher property costs, etc. Toyoda quickly realized that smaller batches, when made efficiently, lead to lower overall costs than large batches do.
In a precision aerospace machining environment, a balancing act is needed. Since CNC Industries machines a large variety of precision parts we cannot afford to have a specialized machine for each part or process that we do. Small machine shops also do not have the luxury of a rolling assembly line between our machines. With these restrictions, and the large amount of processing and manufacturing time that it takes to make a single aerospace part, we are put into a more difficult position that a production facility. We cannot truly operate with no inventory as the goal would be, so we must decide on the ideal inventory to keep on hand.
Precision aerospace machining processes typically have rather long setup times relative to simpler machining processes. This causes the ideal batch size to increase in order to compensate for the lost time on the machine while it is down for setup. At CNC Industries we have worked long and hard to decrease our setup times and have successfully lowered our setup time by 75% over the last 5 years. This has enable us to lower the ideal batch size as well, which in turn allows us to hold less inventory.
In addition to the setup process improvements that we have made over the years, information management is key to efficiently running small batches. Smaller batches will mean more switchovers, more setups, and more jobs running at the same time. With all of these issues, scheduling is both critical and difficult. Job Manager II allows us to have a visual reference of the schedule at any computer throughout our facility and quickly identifies and problems or potential problems at an early stage of the process which allows us to quickly make any necessary adjustments.
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