1.2 MANUFACTURING PROCESSES

Before discussing the rules and planning strategy used, it is important to outline the manufacturing context they are used in.

1.2.1 Basic Factors Considered in Process Selection

There are a number of factors commonly considered when selecting processes. Some of these can be quickly listed, as below (not in order).

• Tolerances

• Material

• Quantity

• Feature Accessibility

• Safety

• Finish

• Cost

The priority of these factors vary depending upon the industry, and the product. The process selected also determines which of these factors are relevant.

1.2.2 Conceptual Process Groups

At present, processes are often described in loose terms. The classifications vary between applications, and therefore it is hard to develop a unified model of all manufacturing processes. A list of processing concepts is given which represents what the author feels is a reasonable division of some modern manufacturing processes. Each of these process groups is considered to be independent, and complementary.

• Molding - Forming amorphous material into a solid shape through the use of a form, or mold.

• Joining - Causing a permanent kinematic bonding between parts through some sort of connection on a molecular level.

• Assembly - A group of parts which form a new part through couplings, fasteners, screws, etc. An assembly requires no bonding.

• Cutting - Creating new parts by severing an existing part.

• Machining - Deliberate removal of material to develop a newer, smaller geometry.

• Finishing - Processes which have imperceptible effect on the geometry.

• Forming - An intentional deformation to produce a new geometry.

• Handling - The physical movement of parts between locations and orientations.

By grouping the processes in this way, they can be matched to geometric functions (eventually the Boolean equation templates will be used). A list is presented below that shows how various processes match the classifications above. While this is not complete, it does indicate the intention of the author. Please note that the classification items vary for each of the following process groups.

• Molding

• Casting

- Gravity Fed Casting

- Hollow Molds

- Green Sand

- Dry Sand

- Core-sand molding

- Cement bonded sand molding

- Carbon Dioxide Process

- Plaster Molds

- Loam Molds

- Shell Molding

- Ceramic Molds

- Graphite

- Permanent Molds

- Consumable Cores

- Precision Molding (Investment Casting)

- Forced Fed Casting

- Die Casting

- Hot Chamber Machines

- Cold Chamber Machines

- Centrifugal Casting

- True Centrifugal Casting

- Semi-Centrifugal Casting

- Centrifuging

- Continuous Casting

- The V-Process (Vacuum Casting)

• Powdered Metals

- Pressure Forming

- Conventional Compaction

- Vibratory Compaction

- Powder Extrusion

- Powder Rolling

- Hot Isostatic Pressing

- Cold Isostatic Pressing

- Explosive

- Forming with Binders

- Pressureless

- Loose Sintering

- Slip Casting

- Slurry Casting

• Plastics

- Casting

- Injection molding

- Compression Molding

- Transfer Molding

- Extrusion

- Rotational Molding

- Open-Mold Processing

- Pultrusion

- Filament Winding

• Joining

- Mechanical Joining

- Riveting

- Welding

- Cold Pressure Welding

- Cold pressure Welding of sheets and wires

- Ultrasonic

- Explosive

- Hot Pressure Welding (Molten Metal)

- Percussion

- Resistance Flash

- Resistance Spot

- Resistance Seam

- Resistance Projection

- Thermit

- Hot Pressure Welding (Solid State)

- Diffusion Bonding

- Friction Welding

- Inertia Welding

- Induction Welding

- Resistance Upset (Butt)

- Fusion Welding

- Arc Welding

- Shielded metal arc welding

- Carbon Arc Welding

- Flux-cored arc Welding

- Stud Welding

- Submerged-arc Welding

- Gas Metal Arc Welding

- Gas-tungsten Arc Welding

- Plasma-arc Welding

- Electroslag Welding

- Gas Welding

- Electron Beam Welding

- Laser Welding

- Sticking

- Brazing and Soldering

- Soldering

- Brazing

- Torch brazing

- Furnace Brazing

- Induction Brazing

- Dip Brazing

- Salt Bath Brazing

- Resistance Brazing

- Adhesives

- Epoxies

- Phenolics

- Polyamide

- Silicones

- Plastics

- Thermal Bonding

- Ultrasonic

• Finishing

- Surfacing

- Hardfacing

- Powdered Metals

- Sizing

- Machining

- Oil Impregnation

- Infiltration

- Heat Treatment

- Steam Oxidizing

- Plating

• Cutting

- Thermal Cutting

- Oxy-fuel cutting

- Arc Cutting

- Conventional Arc

- Air-arc

- Oxygen-arc

- Carbon-arc

- Tungsten-arc

- Air-carbon-arc

- Plasma-arc

- Laser Cutting

- Mechanical Cutting

- Shearing

- Bar Cropping

- Blanking

- Cutting Die Construction

- Sawing

• Forming

- Working

- Rolling

- Metal Drawing

- Wire Drawing

- Tube Drawing

- Extrusion

- Direct

- Indirect

- Hydrostatic

- Impact

- Forging

- Open-die

- Closed-die

- Drop-Forging

- Press-Forging

- Horizontal Forging

- Cold Forming

- Sizing

- Swaging

- Coining

- Cold Heading

- Press operations

- Punching

- Flanging

- Forming

- Rubber forming

- Embossing

- Beading

- Offsetting

- Hydroform

- Bending

- Hemming

- Corrugating

- Wiring

- False Wiring

- Roll Bending

- Rotary Bending

- Drawing

- Deep Drawing

- Ironing

- High Energy Rate

- Explosive Forming

- Electrohydraulic Forming

- Electromagnetic Forming

- Spinning

- Plastics

- Blow Molding

- Thermoforming

- Calandering

• Machining

• Rotational

- Turning

- Lathe

- Cylindrical Turning

- Facing

- Groove Cutting

- Boring and Internal Turning

- Taper Turning

- Thread Turning

- Drilling

- Conventional Drilling

- Boring

- Counterboring

- Spot Facing

- Countersinking

- Reaming

- Tapping

• Prismatic

- Shaping and Plaining

- Horizontal Push-Cut Shapers

- Vertical Shaper

- Planer

- Milling

- Face Milling

- Peripheral Milling

- Grinding

- Surface Grinding

- Cylindrical Grinding

- Internal Grinding

- Centreless Grinding

- Broaching

• Miscellaneous

- Ultrasonic

- Abrasive Jet

- Chemical Machining

- Electrochemical

- Electrodischarge

• Assembly

• Packaging

• Screwing and Bolting

- Manual

- Automatic

- Robotic

• Press Fitting

• Handling

• Small Parts

- Robots

This list is too long, but it is also far from complete. (See Chang [1990], and Dieter [1991] for more information on processes, and their limitations).

1.2.3 Process Data Parameters

Four common process selection parameters listed are Geometry, Material, Tool, and Machine. The machine specified will allow examination of factors like specific tolerances for a machine, horsepower of the machine, pressure of the machine, or other parameters of interest. The tool information will allow access to things such as tool material, tool geometry (including chip breakers, shape of tool, methods of fixation, etc.). Using this information along with workpart geometry and material, the machining process may be selected in terms of tolerance capabilities, time, and cost. Workpart geometry and material also give information about possible processes for the part. The Geometry of the feature (including dimensions, tolerances, and geometric form) to be produced will allow, or disallow a process as a candidate. The material can also be a design factor in selecting a process.

1.2.4 Manufacturing Materials and Process Groups

In some cases materials can determine a process. The list below shows some common processes and a couple of materials that they are suited to.

• Casting

- Cast Steels

- Cast Grey Iron

- White Cast Iron

- Ductile Cast Iron

- Compacted Graphite Cast Iron

- Malleable Cast Iron

- Cast Aluminum and Alloys

- Cast Copper Alloys

- Magnesium Alloys

• Sheet Metal

- Shearing

- Blanking

• etc

More information about processes, and materials is available in Dieter [1991].