introduction manufacturing processes

Introduction to Manufacturing Processes

Product Creation CycleDesign → Material Selection → Process Selection → Manufacture → Inspection → Feedback

Typical product cost breakdown

Products and Manufacturing

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

Manufacturing EngineerSelect and coordinate specific processes and equipment

Industrial EngineerResponsible for the manufacturing system design

Materials EngineerDevelop and select materials based on desired material properties and manufacturing processes

Manufacturing System Designs

Small quantities of products Large variety of productsProducts move through the shop to various machinesGeneral-purpose machines

Job Shop

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Flow ShopLarger quantities of products

Production line

Special purpose machines



Linked-Cell ShopManufacturing and subassembly cells connected to final assembly

Lean production system

One piece flow system



Project ShopProduct being manufactured cannot be easily moved during productionProduction processes are brought to the productExamples: Bridges, ships, large airplanes, locomotives, large machinery



Continuous ProcessLarge plants

Utilized in the manufacture of liquids, oils, gases, and powders



Lean Manufacturing100% “good” units flow from process to process

Integrated quality control (IQC)

All employees are inspectors


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

Utilizes material that has been cast

Modify the shape, size, and physical properties of the material

Hot and cold forming

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)

Wire, rod, and tube drawing – Material is pulled through a die to produce a uniformed cross section

Extrusion – Material is compressed and forced through a die to produce a uniformed cross section


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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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Turning ProcessesOperations that create cylindrical parts

Work piece rotates as cutting tool is fed into the work

Machining Processes

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Turning ProcessesLathes and turning centers

Processes include: Straight, taper, contour turning, facing, forming, necking, parting, boring, threading, and knurling

Machining Processes


Milling 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

Milling Processes

Mills – Vertical and horizontal

Processes include: Surfacing, shaping, forming, slotting, T-slotting, angle, straddle, dovetailing, and slab milling

Machining Processes

Drilling ProcessesOperations that create holes

Cutting tools rotate and are fed into nonmoving secured work pieces

Machining Processes

Drilling ProcessesDrilling and boring machines

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

Machining Processes

Shearing ProcessesOperations 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

Shearing ProcessesMachining Processes

Abrasive Machining ProcessesOperations 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

Thermal and Chemical ProcessesOperations that cut and shape materials through chemical means

No mechanical force is used

Machining Processes

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 ProcessesMechanical Fastening

Use physical force to hold parts together

Mechanical fasteners or part design

Screws, bolts, nails, rivets, cotter pins, retaining clips, and edge design


Joining and Assembly ProcessesWelding

Operations that use heat, pressure, or both to permanently join parts

Gas, arc, stud, spot, forge, roll laminating, resistance, and induction welding


Joining and Assembly ProcessesAdhesive bonding

Bonding of adjoining surfaces by filling the gap between each surface with a bonding material

Glue, cement, thermoplastic, thermosetting, and elastomers


Joining and Assembly ProcessesSoldering and Brazing

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 PrototypingAdditive 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

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

Extrusion

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 ProcessesInjection Molding

Plastic is melted and poured into a mold – No pressure or fillers are required.

Plastics Manufacturing ProcessesCasting

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.

Rotational Molding


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.

Blow Molding


Liquid reactants are mixed and then pressurized into a mold.

No heat is needed. Curing time is typically less than 1 minute.

Reaction Molding

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.

Thermoforming

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.

Crystalline CeramicsMaterial is shaped and then heated to produce a permanent solid.

Manufacturing Importance

Typical product cost breakdown

introduction manufacturing processes

Documents

inspectedutilizes material

mold cavitymolten material

desired material properties

forging slugs of material

pass forging material

tube drawing material

specific processes

desired shape