13. Design For Manufacture And Project Management Flashcards
(26 cards)
How can you plan for accuracy and efficiency ?
- pre production quality assurance
- clear production schedule with deadlines and appropriate QC inspections
- car simulations, a variety of modelling techniques and cost calculations
- working drawings with tolerances
- non destructive testing and destructive testing
What may be used to ensure accuracy in small scale production ?
- measuring devices such as gauges and callipers
What may be used to ensure accuracy in medium scale production ?
- jigs and fixtures required for consistency within the batch
- sophisticated measuring devices
- highly accurate cnc machinery may be used
What may be used to ensure accuracy in large scale production ?
- sample testing of dimensions and other important elements during and after manufacture
- mould replacement cycle to deal with inevitable wear due to heavy use
- measuring methods that do not require high levels of operating skills :
Computerised systems
Go/ no go gauges
Procedures to ensure products are right the first time and every time ?
- pre production cad modelling ( check fit and assembly )
- fea ( finite element analysis ) - check stresses
- mfa ( mould flow analysis ) predict material flow within moulding machine
What are project management systems ?
- total quality management
- scrum
- six sigma
CPA
What is total quality management ( TQM )
Aims to remove waste and make products right the diary time by continuous improvement
- workforce’s views, feedback and teamwork and communication are highly prioritised
What is meant by scrum ?
- main focus is to work as a steam to reach goals in a short time scale
- team goals are specified and individual feedback progress at daily update meetings
- regularity of feedback meetings facilitates quick response to issues that arise
What is meant by sisx sigma ?
- system process improvement to reduce defects to fewer than 3.4 in every million
- procedure minitors asses and improves each stage of design and manufacture
What are the 5 key stages of six sigma ?
- dmaic
D - define issue requiring improvement
M - measure extent of issue
A - analyse where measured issue occurs
I - improve by introducing
C - control the modified proceesss through effective questionaire
What is cpa ?
Critical path analysis
- schedule efficient completion of process stages
- a sequential order of tasks is established for a project or process
- unnecessary waiting time can be identified
- paralleled processing opportunities can then be exploited for maximum efficiency
What is quality control ?
The monitoring , checking and testing of quality assurance tolerance conformity throughout production
How can compliance of materials with the manufacturer’s specification checked ?
- simple visual checks
- chemical analysis of samples ( moisture content or chemical composition )
- colour matching for pigments or paints
How can dimensional accuracy be checked ?
- use of digital measuring devices such as micrometers and digital vernier calipers
- interval sample testing
What is tolerance ?
The level of accuracy acceptable in a particular situation
- depends on the material used for parts as well as their size and function
- components not within tolerance are rejected by QA and QC measures
What are tolerances important ?
- when interchangeability of parts is required
How are tolerances expressed ?
X +_ Y
X is the exact size required and y is the allowable error
What is used to check specific tolerances in mass- production ?
Go/ no go gauge
How is a gauge made ?
With minimum and maximum dimensions for ease of use
What is a go / no go gauge better than tools such as a vernier calliper and micrometer ?
- a specific reading is not required to see if it is suitable and no reed for calibrating tools
What is a go/ no go gauge ?
- they check a single measurement for tolerance range , with a pass or fail reading
What are ways to check for accuracy ?
- go / nogo gauge
- micrometer and vernier calliper to take readings
- probe scanners
- laser scanners
How can probe scanners be used to check for quality control ?
- probe scanners can check predefined measurements of a finished components.
They are highly accurate with automatic comparison with computer 3d cad model
How can non contact lasers be used to check quality control ?
Lasers can scan 1000 of readings per second with a greater accuracy
