Manufacturing Processes for Engineering

CHAPTER 1

What is manufacturing?

- Manufacturing:

In its broadest sense, the process of

converting raw materials into products,

consisting of the design and making of goods,

using various production methods and

techniques

- Automobile has about 15,000 parts,

C-5A transport plane more than 4 M parts

Boeing 747-400 6M parts.

- Origin: Manu factus (made by hand) in Latin

- Manufacture was initially used in 1567 and

manufacturing appeared in 1683

- Manufacturing in U.S.A. and

Production Engineering in E.U. and Japan

- Discrete products or Continuous products

- Value addedness

- Meet design requirements and

specifications

- Produced by the most economical ways

- Quality

- Flexibility of the processes

- Require new materials, production

methods, and computer integration

- Reviewed as a large system

The design process and concurrent engineering

- Concurrent engineering is a systematic

approach integrating the design and

manufacture of products with the view of

optimizing all elements involved in the life

cycle of the product.

- Direct engineering utilizes a database

representing the engineering logic used in

the design of each part of a product. If a

design modification is made on a part. DE

will determine the manufacturing

consequences of that change.

Design for manufacture and assembly

- DFM is a comprehensive approach to

production of goods and integrates the

design process with materials,

manufacturing methods, process planning,

assembly, testing, and quality assurance.

- DFA and DFD – 3-D conceptual designs

and solid models.

Selecting materials

- Ferrous materials (carbon steels, etc)

- Nonferrous materials (aluminium,

magnesium, copper, titanium alloys, etc.)

- Plastics (thermoplastics, thermoset, and

elastomers)

- Ceramics, glass ceramics, glasses,

graphite, diamond

- Composite materials (reinforced plastics,

metal-matrix and ceramic-matrix

- Properties of materials

- Cost and availability

- Appearance, service life, and

recycling

Selecting manufacturing processes

- Casting

- Forming and shaping

- Machining

- Joining

- Finishing

Dimensional and surface finish considerations.

Operational and manufacturing cost considerations.

Consequences of improperly selecting materials and

processes.

Computer-integrated manufacturing

- Machine control systems: NC, CNC,

AC, automated handling of materials,

industrial robots

- Computer technology: CIM

CAD, CAM, CAPP, GT, FMS, JIT, AI,

Expert System, Neural Network,

Quality assurance and total quality management

- Quality must be built into a product – from

design stage through all subsequent stage

of manufacture and assembly. Control the

processes and not products.

- Total quality management (TQM) and quality

assurance

- Statistical process control (SPC)

- Experimental design

Global competitiveness and manufacturing costs

- The design should be as simple as possible

to manufacture, assemble, and recycle.

- Materials should be chosen for the

appropriate manufacturing characteristics.

- Dimensional accuracy and surface finish

specified should be as broad as permissible.

- Because they can add significantly to cost,

secondary and finishing processing of parts

should be avoided or minimized.

Lean production and agile manufacturing

- Lean production or lean manufacturing

involves a major assessment of each of

a company’s activities.

- Agile manufacturing ensures flexibility

in the manufacturing enterprise so it can

quickly respond to changes in product

demand and customer needs.

Environmentally conscious design and

manufacturing

- Reducing waste of materials at their source

by refinements in product design and

reducing the amounts of materials used.

- Conducting R&D in environmentally

safeproducts and manufacturing technologies.

- Reducing the use of a hazardous materials in

products and processes.

- Ensuring proper handling and disposal of all

waste.

- Making improvements in recycling, waste

treatment, and reuse of materials.

Product liability

- The aspects that deal with product

safety and the resource a customer has

if and when a product is defective.

- Protection strategy for legal and

technical aspects for the consequence

of using a product that has

malfunctioned, causing bodily injury, or

even death, and financial loss to a

Organization for manufacture

- View the people in the organization as important

assets.

- Emphasize the important and need for teamwork

and involvement in problem solving and

decision-making processes in all aspects of operations.

- Encourage product innovation and improvements in

productivity.

- Encourage efforts for continuous improvement in

quality

- Increase flexibility of operation for faster response

to product demands in both the domestic and

global marketplace