Transcript
MANUFACTURING PRACTICES
By
Mr.NABAL SINGHAssistant Professor,
Department of Mechanical Engineering,,Jagannath University, Chaksu ,Jaipur
Mail ID:- nabaliitb10@gmail.com
Manufacturing“The Process of Converting Raw
Materials Into Products”
Manufacturing processes
• Manu Factus : Latin for ‘made by hand’
• Definition:• A Well organized method of converting raw material
to end product
• End Product: Value and utility added to output
Manufacturing a Product: General Considerations
• Material Selection
• Processing Methods
• Final Shape and Appearance
• Dimensional and Surface Finish
• Economics of Tooling
• Design Requirements
• Safety and Environmental Concerns
Choosing Methods of ProductionUse a Selection Chart
Economic and Technolgical defination of Manufacturing
Survey of Manufacturing Processes• Casting: expendable mold and permanent mold.
• Forming and Shaping: rolling, forging, extrusion, drawing, sheet forming, powder metallurgy, molding
• Machining: turning, boring, drilling, milling, planing, shaping, broaching, grinding, ultrasonic machining, chemical machining, electrical discharge machining (EDM), electrochemical machining, high-energy beam machining
• Joining: welding, brazing, soldering, diffusion bonding, adhesive bonding, mechanical joining
• Finishing: honing, lapping, polishing, burnishing, deburring, surface treating, coating, plating
Casting ProcessesIntroduction of molten metal into a mold cavity; upon solidification, metal conforms to the shape of the cavity.
Die Casting Sand Casting
Forming and Shaping Processes
Bulk deformation processes that induce shape changes by plastic deformation under forces applied by tools and dies.
Forging
Extrusion
Manufacturing Processesfor Plastics
• Plastics are shipped to manufacturing plants as pellets or powders and are melted just before the shaping process. Polymers melt at relatively low temperatures and are easy to handle.
• Plastics can be molded and formed, as well as machined and joined, into many shapes with relative ease.
Injection Molding of Plastics
Materials
Properties of Materials Mechanical Properties: strength, toughness, ductility, hardness, elasticity, fatigue, creep.
Behavior Under Loading: tension, compression, bending, torsion, shear.
Physical Properties: density, specific heat, thermal expansion, thermal conductivity, melting point, electrical and magnetic properties.
Chemical Properties: oxidation, corrosion, degradation, toxicity, flammability.
Types of Materials
Ferrous Metals: iron and steel.
Nonferrous Metals and Alloys: aluminum, magnesium, copper, nickel, titanium, superalloys, beryllium, zirconium, low-melting alloys, precious metals.
Plastics: thermoplastics, thermosets, elastomers.
Ceramics: glass, graphite, diamond.
Composite materials: reinforced plastics, metal-matrix and ceramic-matrix composites, honeycomb structures.
Ferrous Metals: Applications
• Structural: building structures, concrete reinforcement
• Automotive: chassis, engine parts, drive train, body parts
• Marine: ship hulls, structure, engines
• Defense: tanks, weapons
• Consumer Products: appliances, recreational vehicles, toys, utensils and tools
Nonferrous Metals: Applications
• Architectural: aluminum windows and doors
• Automotive: aluminum engine blocks, copper wiring, mag wheels
• Marine: brass/bronze fittings, bearings, propellers
• Defense: brass shell casings
• Consumer Products: electrical wiring, utensils, jewelry, electronics
Plastics (Polymers)
• Compared to metals, plastics have lower density, strength, elastic modulus, and thermal and electrical conductivity, and a higher coefficient of thermal expansion
• The design of plastic parts should include considerations of their low strength and stiffness, and high thermal expansion and low resistance to temperature.
Plastics: Applications
• Architectural: electrical and thermal insulation, weather seals, carpets, wall coverings, paint
• Aerospace: electrical and thermal insulation, instrument panels, upholstery, seals
• Automotive: body panels, instrument panels, upholstery, electrical and thermal insulation, seals, hoses, tires
• Consumer Products: toys, sporting goods, appliances, tools, utensils, clothing, shoes, packaging