Upload
finn-wixson
View
236
Download
1
Embed Size (px)
Citation preview
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.