In many productions organisations’ inspection is carried out at the end of the process, this means that defects would not be picked up until it reaches inspection, therefore, a large number of defective products may have been produced. This then becomes a cost to the business as production will have to be halted and a root cause analysis will need to be quickly done in order to be able to produce defective free products. In order to avoid this the following methods may be employed:
Built-in quality identifies key attributes that each operation should check prior to performing their own operation. Built-in quality asks each operator to think of themselves as a "customer." The preceding operation is the "supplier." Therefore, as a customer, I have a right to expect a quality product from the supplier. This method reduces the number of defects before discovery and provides feedback to the causing area’s.
You can help achieve built in quality by declaring the following:
I have completed information about this product
I understand the permissible tolerances for this work
I have the skills to complete this work
I know the approved methods to accomplish this work
I have the correct materials to complete the work
I have the correct tools to carry out the work
I have the correct equipment to safely and properly carry out the work
I have adequate workspace to safely carry out and complete the work
The process should be designed so that an individual can be provided with answers to the following questions:
How will I know if I am doing it right?
How will I know if the product is right?
How will I know if I did it wrong?
Only produce good products and services – Quality must be defined accurately so that the person carrying out the operation in question knows exactly what is expected and have all of the necessary tools, equipment, information and skills to make a defect free product every time.
Only accept good products and services – Even if you know how to fix the problem do not accept a non-conformance. If you, do you are accepting a defect and in doing so, you are allowing that defect to continue to occur undetected and unfixed. It is up to everyone to know what is expected and be empowered to send defective product upstream to be corrected.
Only pass on good products and services – Whether you know you made a defect or you recognise a defect from an upstream step and you let it continue in the process because ‘it will be caught by inspection or someone else’ means that you do not comprehend what quality is or you are violating the requirements of built-in quality.
Poka-Yoke is the technique of making an operation "incapable of producing a defect." Poka-Yoke ensures that the right conditions exist before the execution of a process step, therefore, preventing defects from occurring in the first place. Where this is not possible, Poka-Yoke performs a detection function, eliminating defects in the process as early as possible. Common Poka-Yoke devices include 3 pin electrical plugs, USB Ports, different size fuel nozzles, weight checkers, one-way fixtures etc.
Key Points
The abnormal must stand out from the process.
Do not create a defect
Do not accept a defect
Do not pass on a defect
Quality issues in the process do not belong to the Quality Department they are your issues so you must deal with them.
Apply problem solving techniques
If necessary, stop production until the problem is solved
Where possible apply mistake proofing techniques
Create standard work instructions
Organise the work area through 5S and Process flow
Understand what the key characteristics are
Ensure people are well trained
Engage people in the process
Leadership engagement and commitment