CES: Manufacturing Process Selection

Solution.pdf

1. Introduction

 

CES software is a tool designed to aid in the process of materials and manufacturing process selection.  To this end it can be used as:

 

(i) a database of information on materials and processes

 

(ii)  a selection tool for materials and/or processes

 

CES is a powerful tool in helping to choose the most appropriate materials and manufacturing processes for engineering components.  In this module (EAT 227), we are going to concentrate on process selection.  Next year, in the module EAT341/342, we will turn our attention to materials selection.

 

In terms of materials selection, how do you go about choosing the best material for a given engineering application?  What material(s) would be best suited for the manufacture of (say) bicycle forks, flywheels or pressure vessels?  Knowing the right questions to ask makes the process easier.So, what sort of questions do we need to ask to make sure we get the correct choice?  Such factors include cost, performance (e.g. mechanical, thermal), size, shape etc.   CES uses a particularly strong but simple methodology to aid the materials selection process.

 

In terms of process selection, how do you go about choosing the best manufacturing process for a given component?  For instance, how would you select a process to manufacture large steel pressure vessels?  How would you manufacture a polyethylene milk carton?  To answer such questions you need to know what distinguishes one manufacturing process from another. What questions must be asked to decide which manufacturing process is best?

 

The methodologies employed within CES to aid selection of either materials or processes are quite similar.  Each relies on knowing the critical questions to ask.

 

 

In the task which is described below, you will gather much of your information from CES.  However, it is expected that you will add value by sourcing information from outside of CES where appropriate and acknowledge/reference these sources correctly.

2. The Task

 

 

Part 1:  Navigation through Processes

 

1. Open CES software. Choose Aerospace database.
2. In “Browse” mode, select Table: “Process Universe” and Subset: “All Processes”.

 

3. Choose one process from each of the 3 categories available (Joining, Shaping and Surface Treatment).

 

4. In your own words, give a summary of each of the 3 processes chosen. For each process, make sure you include information on (i) the nature of the process, (ii) the types of materials which can be processed in this way and (iii) the characteristics of the components which are produced by the process (size, shape, dimensional tolerance etc) and (iv) economics of the process.

 

 

 

Part 2:  In-Depth Case Study of Process Selection

 

1. In Canvas, or from within CES, open the “Case Studies - Manufacturing Processes” document. Choose one of the process selection case studies presented. You may choose a case study from elsewhere if you wish.

 

2. You are now going to use CES to work through the chosen process selection exercise,generating all selection charts manually.

 

3. Click “Select” tab.

 

4. Choose the appropriate “Process Universe” category (probably “Shaping”) for your chosen process selection case study.

 

5. Reproduce every selection step (i.e. plot selection charts etc) exactly as described in the case study.

 

6. Provide your own commentary which shows clearly how you perform each step of the selection exercise and which links them together.

 

7. Write an overview of your process selection case study methodologyin your own words.

 

 

Part 3:  Economic and Environmental Impacts of Material and Manufacturing Process Selection

 

This is an open-ended exercise which allows lots of scope for personal interpretation.

 

Three materials are proposed as the likely candidates for a car component. 

 

These are:

 

1. Low Alloy Steel shaped via Rolling (a deformation process)
2. Age Hardening Aluminium Alloy shaped via Extrusion (a deformation process)
3. CFRP shaped via Resin Transfer Moulding

The choice of material will affect:

 

• the cost of the component
• the manufacturing process used to shape the component
• the mass of the component (assume 20kg for steel component, 12 kg for aluminium component, 7 kg for CFRP component)
• the environmental impact of the component (in terms of energy and CO₂) over its whole life cycle
• the fuel consumed over the lifetime of the vehicle
• any other variables which you consider important

Use the Level 2 CES databases and the CES Eco-Audit tool to investigate the relative impacts of the above factors [(a) through (f) above] associated with the use of this component within a car with a usable life of 20 years and that travels within the UK:

 

1. 5,000 km pa
2. 10,000 km pa

• 25,000 km pa

1. 50,000 km pa

Make whatever reasonable assumptions you feel appropriate, but do specify these.  Examples might include manufacturing batch size, fuel costs, component transport mode to end user etc.