QUALITY + MAINTENANCE MANAGEMENT Flashcards
Ways to define quality?
- Transcendent: views quality as ‘innate excellence’. eg companies with a reputation for ‘excellence’ like Rolex or Rolls Royce
- Manufacturing based: product being ‘free of errors’ e.g Toyota has a strong reputation for reliability.
- User-based approach: ‘fit for purpose’ i.e dependent on what the user values / wants in a product
- Product based: defined by measurable set of characteristics. eg car will work for 5 years without maintenance and do a certain mpg.
- value-based: balance between cost and price, eg fast food or ryanair.
Define quality?
How consistently a product conforms to customers expectations
What causes perceptions of good/bad quality?
Gaps between customers expectations and the percieved actual quality.
What are the 4 quality gaps?
Gap 1: customer specification - operation’s specification
Mismatch between internal quality spec of the firm and the spec expected by customer. eg an airline charging for coffee when the customer expects it to be free.
Gap 2: concept - specification
Mismatch between the product concept and the way that the firm has specified quality internally. e.g the concept of a car was to be energy efficient and cheap, but the inclusion of a catalytic converter has increased the price and made it less energy efficient.
Gap 3: quality specification - actual quality
Mismatch between actual quality of a product provided by the operation and the internal quality specification
e.g a food truck worker giving people much larger portions than specified internally by the food truck. May lead to people being disappointed in future after their expectations have been raised
Gap 4: actual quality - communicated image
Gap between marketing image and the real quality. eg a McDonalds burger looking incredible on a billboard but much worse in real life.
What are the 6 steps to a quality management plan?
- Define characteristics of product
- Decide how to measure each characteristic
- Set quality standards
- Control quality against standards
- Find + correct sources of error
- Continue to make improvements
What are some general product characteristics (with reference to quality)?
- Functionality: how well the product ‘does the job (includes performance and features)
- Appearance: sensory characteristics (eg aesthetics, smell, feel)
- Reliability: consistency of products performance over time
- Durability: the total useful life of the product
- Recovery: the ease of rectifying problems with the product.
Variables vs Attributes?
-Variables can be quantified easily as continuous real numbers
-Attributes are assessed by judgement and are dichotomies (i.e only have 2 states, good/bad, OK/ NOT OK)
What are the 3 major decisions of quality control?
- Where should quality be controlled
- How should tests be performed
- Check every product or take a sample?
Expand on where should quality be controlled?
Choice between (or combo of)
- At the start, to inspect raw materials or bought in components
- During the process, maybe before a costly part of the process or after a well known failure point
- At the end: to check if quality is acceptable to be delivered to consumer
Expand on how should quality checks be performed?
- Statistical process control (SPC): Monitors products and attempts to distinguish between normal variations and unnatural (assignable) variation
- Acceptance sampling: batches of products are inspected to determine whether or not to accept the entire batch. Informed by the ratio of defectives to the acceptable products in a sample.
Expand on check every product or take a sample?
- Very unrealistic to inspect every product for defects; impractical, time consuming and costly. Therefore sampling is used
What are Errors type 1 and 2?
Type 1 = false positive - sample indicates a trait in the population but in reality the population as a whole does not possess that trait. e.g NERF checks 20 out of 1000 toy guns for trigger defects and they all happen to have an issue, they may assume that all 1000 toy guns have trigger issues. They would be making a type 1 error.
Type 2 = false negative. Same but reverse.
What is total quality management (TQM)?
3 main objectives:
1. achieving customer satisfaction
2. improving continuously
3. involving the entire workforce in quality management
Aspires to meet the customers requirements first time, every time. Quality must therefore be embedded in every stage.
Describe / define inspection?
- performed before, during and after manufacturing
- involves measurement techniques to ensure that products conform to design specifications (dimensions, tolerances, surface finish etc)
What is non-destructive testing?
Techniques that don’t damage the sample
