Quality of design

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In the article titled "Quality of Conformance", we discussed that quality can be broadly classified into Quality of Conformance and Quality of Design. Quality of Conformance is basically meeting the specified quality or the ability to hold to the specified quality of design. Quality of design is to do with meeting or exceeding customer requirement by improved design.In the article titled "Quality of Conformance", we discussed that quality can be broadly classified into Quality of Conformance and Quality of Design. Quality of Conformance is basically meeting the specified quality or the ability to hold to the specified quality of design. Quality of design is to do with meeting or exceeding customer requirement by improved design.

In the article titled "Quality of Conformance", we discussed that quality can be broadly classified into Quality of Conformance and Quality of Design. Quality of Conformance is basically meeting the specified quality or the ability to hold to the specified quality of design. Quality of design is to do with meeting or exceeding customer requirement by improved design.

 

Quality of Design is important because it takes away a lot of uncertainty in the final product quality; though the contribution of design cost is only about 5% of the product cost, it has a 70% influence on quality, manufacturability, serviceability and general acceptance in the market.

 

Focusing on the quality of design indeed has many benefits, primarily the product quality itself and then the enhanced application of the product and it also has impact on easy of manufacturing, assembly and service. There are many tools and methods that go in enhancing the quality of design, beginning with basic quality reviews and other approaches like Design for Six Sigma (DFSS), Concurrent Engineering, Production Preparation Process (3P) and many more. Preventing product failures is one of the top priorities of the product designer. Product failures occur both internally as well as externally. Internal failures can lead to delays and waste of material and time; while external failures can impact customer confidence and urge customers to turn to competitors. Design for manufacturing and Design for Assembly can help satisfy internal customers. Design for Assembly will minimize production cost by focusing on the number of parts handled and easy of assembly. Design for manufacturing helps in selecting the most effective material and processes used in production.

 

The minimum an organization should comply with to make design quality robust is to have design reviews and by planning for product and process design and development. This process has been very well documented and standardized by the Automotive Industry Action Group (AIAG) in the APQP requirements, which is now an integral part of the ISO/TS-16949 manual. The Advanced Product Quality Planning (APQP) system has 5 phases- a) Plan and Define the Program, b) Product Design and Development, c) Process Design and Development, d) Product and Process Validation, and e) Feedback Assessment and Improvement Action. The key here is about planning for quality and making sure that first of all the customer requirements are well understood and captured and defined. Tools like QFD (Quality Function Deployment) may be used to translate customer requirements to technical requirements. In the design phase one of the key activity should be to foresee potential failures and take appropriate preventive action and this preventive action tool is called FMEA (Failure Mode and Effects Analysis). Reviews by cross functional teams of course are vital during the design phase; and the FMEA and reviews are applicable for the design of the process as well. There must also be a continuous process of feedback and review and before start of bulk production a pilot run is carried with an opportunity for the customer to witness and feedback on process and product quality.

The minimum an organization should comply with to make design quality robust is to have design reviews...

What all these activities will lead to is a more robust design that will prevent or reduce failures after shipment of product. When Quality of Conformance is not met, there would be failures but most failure would be something that can be expected because of poor controls during manufacturing, but failure caused primarily due to design issues normally come as a jolt from the blue. Let's look at an example of hair driers wherein there are a couple of failures due to the motor getting burnt. Well if the burning issue happens to a large number of hair driers, basically caused by a poor design of the thermal or high current overload protector, then this would be an issue that was not anticipated and it being a major design failures, all products cutting across manufacturing dates and production batches and raw materials used will fail eventually in the field. Another example could be of an airbag in the car, getting activated during the normal running condition, in the event of some minor shocks, basically due to poor design of the airbag. Safety is an important aspect of a good design and Design FMEA reviews help to reduce the occurrence and severity of a potential hazard, for example how to improve design to reduce the probability of a brake failure in a car or in the event of a potential failure, can there be an advance warning so that the driver can take precautions or bring the car to a halt before the failure can actually occur n

 

Pradeep Kumar E.T. A Master Black Belt in Six Sigma , is the Country Manager- Operational Excellence with Tyco Electronics Corporation India Pvt Ltd. Feedback can be e-mailed to pradeep@businessgyan.com

 

Issue BG93 Dec08