manufacturing processes. categories of processing methods: – casting – forming and shaping –...

Manufacturing Processes

Manufacturing Processes

• Categories of processing methods:– Casting – Forming and shaping– Machining– Joining– Finishing

Casting

• Sand Casting: Engine blocks, cylinder heads, pump housings.

• Shell mold casting: Gear housings, connecting rods.

• Expandable pattern casting: Crankshafts, brake components, machine bases.

• Vacuum casting, Die casting, Slush casting……

Casting

• Plaster mold Casting: (High dimensional accuracy)

Locks, gears, valves, toolings.

• Ceramic mold Casting: (High dimensional accuracy) Impellers, cutters for machining, dies for metalworking.

• Investment Casting: (High dimensional accuracy) http://www.youtube.com/watch?v=BX8wGUPz1w&feature=related

Forming

• Rolling: plates ( 5 to 12 in thk), sheets (upto 6 mm thk) threads, seamless tubes and pipes.• Forging: Aircraft landing gear, jet engine shafts, structural components.

Changing the shape of an existing solid body

Forming

• Extrusion and Drawing: door and window frames, tubing, railings rods, shafts, wires. • Sheet metal forming: 1. Shearing 2. Bending metal desks, cabinets, car bodies, fuselage beverage cans.

http://www.youtube.com/watch?v=qTUMbVNf1Xc&feature=related

http://www.youtube.com/watch?v=nA8y__BMl-o&feature=related

http://www.youtube.com/watch?v=q5Wlr6Co5SI

Sheet Metal

Machining

Cutting: Turning, Shaping, Milling, Drilling. http://www.youtube.com/watch?v=874DNEvCc-c

Abrasive: Grinding, Honing, Lapping, Buffing, Polishing.

Non-traditional: Electrochemical machining, laser beam machining.

Joining / FabricationWelding : Fusion welding: Plasma Arc, Electron beam.

Solid State: Resistance welding.http://www.youtube.com/watch?v=b2n_kpLXwY8

Brazing and Soldering

Adhesive bonding

Mechanical fastening

Manufacturing Processes

Selecting a Manufacturing Process depends on:

• Size• Thickness• Shape Complexity• Material• Cost

DFM considerations

Save material in Stamping from stock sheet metal

DFM considerations

DFM considerationsSave material in Stamping from stock sheet metal Uniform cooling when heat treating

DFM considerationsSave material in Stamping from stock sheet metal Uniform cooling when heat treating

Overcome practical difficulty in grinding near a corner

DFM considerationsSave material in Stamping from stock sheet metal Uniform cooling when heat treating

Eliminate expensive reinforced weldOvercome practical difficulty in grinding near a corner

DFM considerations

DFM considerationsAvoid flat bottom holes, give room for tool clearance and chips

DFM considerationsAvoid flat bottom holes, give room for tool clearance and chips

Limit machining operations

DFM considerationsAvoid flat bottom holes, give room for tool clearance and chips

Limit machining operations

Sharp corners decrease the strength

Sheet MetalFlat pattern Bend Final product

Compresses on the Inside, Stretches on the outside

Calculating length of Flattened pattern: Bend Allowance.

Empirical formula:BA = (0.017453 R + 0.0078 T) N

Where R = radius of bend T = metal thickness N = number of degrees of bend

Sheet MetalCalculate Bend Allowance for

R = 0.075 inchThickness T = 0.125 inchAngle N = 90

BA = (0.017453 x 0.075 + 0.0078 x 0.125 ) 90 = 0.20555775 0.2056 in.