Introduction & basic materials used in foundry, Introduction to casting process and steps involved, Patterns, Study of important moulding process
Introduction: Definition, Classification of manufacturing processes. Metals cast in the foundry-classification,factors that determine the selection of a casting alloy.
Introduction to casting process & steps involved: Patterns: Definition, classification, materials used for pattern, various pattern allowances and theirimportance. Sand moulding: Types of base sand, requirement of base sand. Binder, Additives definition, need and types;preparation of sand moulds. Melding machines- Jolt type, squeeze type and Sand slinger. Study of important moulding process: Green sand, core sand, dry sand, sweep mould, CO2mould, shellmould, investment mould, plaster mould, cement bonded mould. Cores: Definition, need, types. Method of making cores, Concept of gating (top, bottom, parting line, horn gate) and risers (open, blind) Functions and types.
Melting and Metal Mold Casting Methods, Melting furnaces, Casting using metal moulds
Casting using metal moulds: Gravity die casting, pressure die casting, centrifugal casting, squeeze casting, slush casting, thixocasting, and continuous casting processes.
Melting furnaces: Classification of furnaces, Gas fired pit furnace, Resistance furnace, Coreless induction furnace, electric arc furnace, constructional features & working principle of cupola furnace.
Solidification and Non-Ferrous Foundry Practice, Fettling and cleaning of castings, Nonferrous foundry practice
Solidification: Definition, nucleation, solidification variables. Directional solidification-need and methods. Degasification in liquid metals-sources of gas, degasification methods.
Fettling and cleaning of castings: Basic steps involved. Sand Casting defects- causes, features and remedies.Advantages & limitations of casting process
Nonferrous foundry practice: Aluminium castings – advantages, limitations, melting of Aluminium using lift-out type crucible furnace. Hardeners used, drossing, gas absorption, fluxing and flushing, grain refining, pouring temperature. Stir casting set up, procedure, uses, advantages and limitations.
Welding process, Special type of welding
Welding process: Definition, Principles, classification, application, advantages & limitations of welding. Arcwelding: Principle, Metal arc welding (MAW), Flux Shielded Metal Arc Welding (FSMAW), Inert Gas Welding (TIG & MIG) Submerged Arc Welding (SAW) and Atomic Hydrogen Welding (AHW).
Special type of welding: Resistance welding principles, Seam welding, Butt welding, Spot welding andProjection welding. Friction welding, Explosive welding, Thermit welding, Laser welding and Electron beam welding.
Metallurgical Aspects in Welding, Soldering, Brazing, Gas Welding
Soldering, Brazing, Gas Welding: Soldering, Brazing, Gas Welding: Principle, oxy-Acetylene welding, oxy-hydrogen welding, air-acetylene welding, Gas cutting, powder cutting.
Metallurgical Aspects in Welding Structure of welds, Formation of different zones during welding, Heat Affected Zone (HAZ), Parameters affecting HAZ. Effect of carbon content on structure and properties of steel, Shrinkage in welds& Residual stresses. Concept of electrodes, filler rod and fluxes. Welding defects- detection, causes & remedy.
Methods used for inspection of casting and welding. Visual, magnetic particle,fluorescent particle, ultrasonic. Radiography, eddy current, holography methods of inspection.