Design for Manufacture Flashcards
For a symmetrical distribution what is the tolerance range
2tolerance (=2ztheta)
What range should the value for z fall in
4 - 7.5 theta (1 in 63ppm to 0 ppm)
How does asymmetrical distribution occur
tool wear can give consistent bias
What is a house of quality
it helps to convert customer requirements into engineering requirements
What is a product footprint
Product footprint defines the brand
What is the difference between ‘first-to-market’ and ‘fast follower’
first-to-marker seek the ‘first mover advantage’ through premium prices. Other companies may prefer to be ‘fast followers’ to learn from the mistakes of the first-to-market
What kind of order can products be made for
Engineering to order (ETO) Make to order (MTO) Assemble to order (ATO) Make to stock (MTS) Ship to stock (STS)
What is mass customization
Its a marketing technique that combines the flexibility and personalization of custom-made products with the low unit costs associated with mass production
What is product architecture
The scheme by which the function of the product is allocated to physical components and the specification of interactions between physical components
What are the advantages of modular units
Ease of maintenance, quality control over assembly, sealed for life
What are the disadvantages of modular units
Small defects cant be easily repaired, requires high volumes to make feasible
What are the advantages of platform design
Easier inventory management/smaller number of parts Lower development costs Increased quality Global standardization Greater product variety
What is the best way to achieve low mass and volume
have integrated products with minimal interfaces
What is the best way to minimise complexity
best to have a modular design with sub-assemblies and standard interfaces
What is the purpose of quality management
it ensures adequate paper trails for design reviews, materials sourcing, component sourcing, product testing and company decision making
Name 2 quality standards
BS7000 Design Management Systems
ISO 9000 Quality Assurance
What is the 6 sigma rule
If manufactured parts have a normal distribution such that six sigma falls within the tolerance limits then there will be very few failures
What is lean manufacturing
Lean manufacturing is a method for minimizing waste within a manufacturing system without sacrificing productivity
What is a poka yoke
any mechanism in a lean manufacturing process that
helps an equipment operator avoid mistakes
For an asymmetrical distribution around the mean, what is the equation for the worst case scenario
z_2 = | x_m - L_2 | / sigma
What are Cp and Cpk
Process capability numbers (for symmetrical and asymmetrical respectively)
What is Cp equal to
t/3*sigma
What is Cpk equal to
x_m – L_n | / (3*sigma)
What does a house of quality table look like?
Customer requirements (column list); customer priority (1-5); Engineering requirements (row list) Correlation denoted by 1, 3 or 9
What is house of quality used for
Converting customer requirements into engineering requirements
What does Total quality management (TQM) embody?
TQM emphasizes right first time, continuous quality improvement and prevention over inspection
What must be considered when defining product architecture?
What is the sales volume? What is the desired performance? Should the product be adaptable or upgradeable (modular)
