Instructions

Your company has been asked to manufacture compressor wheels for the turbocharger market.  The compressor wheel is shown in Figure 1 and is to be manufactured in an aluminium alloy.  The mechanical properties required can be met by either wrought, cast or powder aluminium alloys providing the component is fully dense and defect free.  The design demands a high level of dimensional accuracy and integrity because it rotates at high speed and the presence of material defects may result in premature fatigue failure.  Depending on the primary manufacturing route chosen some final machining may be necessary to achieve the dimensional accuracy required for successful operation but this should be kept to a minimum.

Your newly appointed Managing Director has asked you to submit a report recommending how you propose to manufacture these compressor wheels based on two scenarios:

• The production of 100 components per annum
• The production of 100000 components per annum

In this report you should justify your choices of manufacturing process based on considering which manufacturing processes could, and could not, be used to produce this part and the advantages and disadvantages associated with the possible processes.  Some advice on answering this question is given overleaf.  The length of the report should not exceed 1500 words.  Please provide a word count for your submission.

Advice on answering this question

In your introduction to your report you should explain briefly to your newly appointed Managing Director the factors that determine the choice of manufacturing process.  In the main body of your report you should discuss briefly the reasons why some manufacturing processes are unsuitable to manufacture this specific part and then describe, in some detail, processes that might be suitable to produce this high quality component, stressing the advantages and disadvantages of these processes.  You should play particular attention to the detailed shape of the part and the requirement for high material integrity, i.e. the production of parts with low defect levels.  Your final choice/s of process then should be justified bearing in mind the number of compressor wheels required followed by your recommendations.

Thus marks will be awarded under the following headings:

1. Introduction – factors which determine the choice of manufacturing processes
2. Manufacturing processes not possible/not suitable
3. Manufacturing processes possible/suitable
4. Detailed discussion of how to produce this specific shape
5. Discussion of how to achieve high material integrity in aluminium alloys
6. Analysis of suitability for producing 100 and 100000 parts
7. Recommendations

Note, in order to get high marks you will be expected to have carried out some additional reading.  Your sources of information should be referenced.