Zero-defect manufacturing: How do they do it?
One of the main ideas within smart manufacturing is aiming for a zero-defect production. The benefits are obvious: less waste of resources, time and money. In addition, zero-defect manufacturing is beneficial for the work atmosphere, the environment and lead times.
Achieving a zero-defect production can be split into two goals: error prevention and error detection. By zero-defect production we understand that errors will always be there, but the goals is that, in the end, no defective products are produced. All products measure within the quality limits. In order to reach this, all errors that take place during production have to be detected and corrected. Error prevention and error detection each have their own approach.
1. Error prevention
Prevention is better than cure. This also applies in a production process. You want to prevent mistakes from being made, so the room for variation in production must be as small as possible. This can be done by simplifying and standardising the production process, both for machines and for manual actions.
The first, and most obvious, solution is to make a production line failsafe. This way, only correct production situations are allowed and it is physically almost impossible to make mistakes. For example, a machine that only starts when the door is closed or when it has reached the right temperature. The use of product moulds or jigs is also part of the solution. Products are always correctly positioned since they have to fit into the jigs exactly.
Visual aid tools can also be used. These tools inform the operators and technicians about the correct procedures during production. Tools can be workplace instruction cards, arrows or symbols.
2. Error detection
As mentioned above, errors can never be ruled out completely. In reality, there will be errors in a production process, both human and mechanical / software related. If the errors are not captured by the error prevention solutions, faulty products can enter the production process. Faults must be detected in time to produce zero-defect.
Visual control instruments warm operators and technicians about possible errors in the production process.
In addition to the above, error detection is important in order to be able to adjust the production process in time when undesired variation occurs in the output quality. The critical elements of a product or process can be measured using sensors or vision systems. When quality measurement data is meticulously monitored, quality reduction can be detected even before defects occur. This way, producing defective products can be avoided. By using data in a smart way, with the help of machine learning, the system will become better at detecting quality reduction earlier on.
Zero-defect manufacturing after error detection
When an error occurs or there are defective products in the output, the following steps can be taken to prevents these errors from happening again:
Describe the defect or error in an objective manner. Do not draw any conclusions yet.
Measure the frequency and severity of the problem
Analyse the production process and trace the cause of the problem. Do not start seeking a solution until the actual cause is clear. A good method for finding the cause is the 5-Why method: name the problem and have someone ask ‘Why?’ five times in a row. This forces you to think beyond the obvious causes and makes it easier to get to the core of the problem.
Address the root of the problem. Develop and implement a good solution for error prevention or error detection.
Measure the effect of the implemented solution and start the cycle again, if necessary.
2. Error detection
Finally, working towards a zero-defect production requires a practical approach. A lot of errors can be avoiding with both simple and more complex solutions. These solutions are often people-oriented, but improving machines and making them failsafe is often possible as well. Zero-defect production is within reach!
Curious to find out which steps you can take toward a zero-defect production? STT Products is happy to take a look and think along with you. We have been helping manufacturing companies optimise their production processes for 35 years. We do this by concepting, engineering and realising smart technical solutions.