Introduction to Manufacturing
Processes

Products and Manufacturing
Design → Material Selection → Process
Selection → Manufacture → Inspection →
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Typical product cost breakdown

Manufacturing Process
A sequence of operations and processes designed to create a specific product
The process of turning materials into a product
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Engineers in Manufacturing
Select and coordinate specific processes and equipment
Responsible for the manufacturing system design
Develop and select materials based on desired material properties and manufacturing processes

Manufacturing System Designs
Small quantities of products
Large variety of products
Products move through the shop to various machines
General-purpose machines
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Manufacturing System Designs
Larger quantities of products
Production line
Special purpose machines
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Manufacturing System Designs
Manufacturing and subassembly cells connected to final assembly
Lean production system
One piece flow system
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Manufacturing System Designs
Product being manufactured cannot be easily moved during production
Production processes are brought to the product
Examples: Bridges, ships, large airplanes, locomotives, large machinery
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Manufacturing System Designs
Large plants
Utilized in the manufacture of liquids, oils, gases, and powders
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Manufacturing System Designs
100% “good” units flow from process to process
Integrated quality control (IQC)
All employees are inspectors
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Basic Manufacturing Processes
Casting and Foundry
Forming or Metalworking
Machining
Joining and Assembly
Rapid Prototyping
Other

Casting and Foundry Processes
In one step raw materials are transformed into a desirable shape
Parts require finishing processes
Excess material is recyclable
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Basic Casting Process
A mold is created – A cavity that holds the molten material in a desired shape until it is solidified
Multiple-use mold
Single-use molds
Material is heated to a specified temperature
Molten material is poured into a mold cavity
Molten material solidifies into the shape of the cavity
Casting or mold is removed
Casting is cleaned, finished, and inspected

Forming and Metalworking Processes
Utilizes material that has been cast
Modify the shape, size, and physical properties of the material
Hot and cold forming
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Forming and Metalworking Processes
Rolling – Material passes through a series of rollers, reducing its thickness with each pass
Forging – Material is shaped by the controlled application of force (blacksmith)

Forming and Metalworking Processes
Extrusion – Material is compressed and forced through a die to produce a uniformed cross section
Wire, rod, and tube drawing – Material is pulled through a die to produce a uniformed cross section
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Forming and Metalworking Processes
Cold forming and forging – Slugs of material are squeezed into dies

Machining Processes
Controlled removal of material from a part to create a specific shape or surface finish
Cutting element is used
Movement must exist between the part and cutting element
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Machining Processes
Operations that create cylindrical parts
Work piece rotates as cutting tool is fed into the work
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Machining Processes
Lathes and turning centers
Processes include: Straight, taper, contour turning, facing, forming, necking, parting, boring, threading, and knurling
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Machining Processes
Operations that create flat or curved surfaces by progressively removing material
Cutting tools rotate as the work piece is secured and fed into the tool

Machining Processes
Mills – Vertical and horizontal
Processes include: Surfacing, shaping, forming, slotting, T-slotting, angle, straddle, dovetailing, and slab milling

Machining Processes
Operations that create holes
Cutting tools rotate and are fed into nonmoving secured work pieces

Machining Processes
Drilling and boring machines
Processes include: Drilling, counter drilling, step drilling, boring, counter boring, countersinking, reaming, spot facing, and tapping

Machining Processes
Operations that break unwanted material away from the part
A material is placed between a stationary and movable surface. The movable surface (blade, die, or punch) applies a force to the part that shears away the unwanted material.

Machining Processes
Automated hole punch, squaring shear, and rotary cutter
Processes include: Shearing, blanking, cutoff, and parting; punching, perforating, and slotting; notching, lacing, and trimming

Machining Processes
Operations in which small particles of materials
(abrasives) remove small chips of material upon contact
Drum, disc, and belt sanders; surface, vertical and horizontal spindle; disc grinders; media blaster; tumblers

Machining Processes
Operations that cut and shape materials through chemical means
No mechanical force is used
Electrical discharge, electrochemical, chemical, laser, electron beam, flame cutting, and plasma-arc cutting
Processes include: Grinding, sawing, cutting, machining, milling, blanking, and etching

Heat Treating Processes
Controlled heating and cooling of a material to alter its properties while maintaining its shape
Properties include: Strength, toughness, machinability, wear resistance, and corrosion resistance
90% of heat treating is preformed on steel and other ferrous metals

Heat Treating Processes
To aid in the manufacturing process, materials can be treated to be weak and ductile and then can be re-treated to provide high strength.
Can also occur incidentally during the manufacturing process

Joining and Assembly Processes
Can you think of a product with only one part?
Most products consist of multiple parts that are assembled to form a finished product.
Typical assembly processes include:
Mechanical fastening; soldering and brazing, welding; adhesive bonding

Joining and Assembly Processes
Use physical force to hold parts together
Mechanical fasteners or part design
Screws, bolts, nails, rivets, cotter pins, retaining clips, and edge design
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Joining and Assembly Processes
Operations that use heat, pressure, or both to permanently join parts
Gas, arc, stud, spot, forge, roll laminating, resistance, and induction welding
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Joining and Assembly Processes
Bonding of adjoining surfaces by filling the gap between each surface with a bonding material
Glue, cement, thermoplastic, thermosetting, and elastomers
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Joining and Assembly Processes
Operation in which metal surfaces are bonded together by an alloy
Heated molten alloy flows between the adjoining surfaces
When the heat is removed, the molten metal solidifies and the metal surfaces are bonded
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Rapid Prototyping
Additive process
Parts are produced directly from software applications
Common rapid prototyping systems include: stereolithography (SLA), selective laser sintering (SLS), fused deposition modeling
(FDM), laminated object manufacturing
(LOM), digital light processing (DLP)

Rapid Prototyping
Finished parts can be field tested depending upon building material
Created parts can be used to create a mold
Modifications to design can be implemented quickly

Other Manufacturing Processes
Testing
Transportation
Material handling
Packaging
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Material-Specific
Manufacturing Processes
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Plastics Manufacturing Processes
A rotating screw forces plastic through a heating chamber and then through a heated die
Produces long plastic parts with uniform cross sections

Plastics Manufacturing Processes
Heated plastic is forced by a movable plunger through a nozzle and then into a mold. The material fills the mold and then is cooled.
Most widely used high-volume production process

Plastics Manufacturing Processes
Plastic is melted and poured into a mold –
No pressure or fillers are required.
A closed mold is filled with a predetermined amount of plastic. The mold is heated, rotated, and then cooled to create a hollow plastic object with uniform wall thickness.

Plastics Manufacturing Processes
A solid bottom hollow tube is placed between two mold halves and heated.
The heated tube is then expanded into the sides of the mold with compressed air.

Plastics Manufacturing Processes
Plastic sheets are heated over an open mold to a working temperature. Once workable, a vacuum is applied to the mold, forcing the plastic sheet to take the shape of the mold.
Liquid reactants are mixed and then pressurized into a mold.
No heat is needed. Curing time is typically less than 1 minute.

Ceramic Manufacturing Processes
Two distinct classes of materials and processes exist.
Glass is heated to a molten state, shaped by viscous flow, and then cooled to produce a solid.
Material is shaped and then heated to produce a permanent solid.

Manufacturing Importance
Typical product cost breakdown