Classification Of Manufacturing Processes 1 4f6h1o

CLASSIFICATION OF MANUFACTURING PROCESS

Classification of Manufacturing Processes

A) Primary Shaping Processes

C) Surface Finish Process

E) Processes Effecting Change in surface Properties

B) Secondary

Forming

Sheet Metal work

Machining / chip removal

D) Assembly / ing Process

F) Unconventional Manufacturing process

A)

Primary Shaping Processes

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Casting Manufacturing process by which a liquid material is poured into a mould which contains a hollow cavity of the desired shape and allowed to solidify. The solid casting is then ejected or broken out to complete the process.

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Forging Shaping the metal, after heating to a desired temperature (up to the plastic / red hot stage) by using localized compressive force. Forging is done by a smith using hammer, press, furnace and anvil.

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Extruding Extrusion is a process used to create objects of a fixed cross-sectional profile. A material is pushed through a die of the desired cross-section. The two main advantages of this process over other manufacturing processes are its ability to create very complex cross-sections and work materials that are brittle, because the material only encounters compressive and shear stresses. It also forms finished parts with an excellent surface finish

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Rolling The process of shaping metal by ing them through "rollers" or "rolls" held at a controlled distance or separation.

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Sheet Drawing In drawing, a blank of sheet metal is restrained at the edges, and the middle section is forced by a punch into a die to stretch the metal into a cup shaped drawn part. This drawn part can be circular, rectangular or just about any cross-section.

• Wire Drawing Wire drawing is a metalworking process used to reduce the diameter of a wire by pulling the wire through a single, or series of drawing dies.

• Powder Metal Forming The metal powder is compacted by placing in a closed metal cavity (the die) under pressure. This compacted material is placed in an oven and sintered in a controlled atmosphere at high temperatures and the metal powders coalesce and form a solid.

• Plastic Technology 1.

Injection molding - Material is fed into a heated barrel, mixed, and forced into a mold cavity where it cools and hardens to the configuration of the mold cavity.

1.

Thermoforming is a manufacturing process where a plastic sheet is heated to a pliable forming temperature, formed to a specific shape in a mold, and trimmed to create a usable product.

1.

The blow molding process begins with melting down the plastic and forming it into a parison or preform. The parison is a tube-like piece of plastic with a hole in one end in which compressed air can through.The basic process has two fundamental phases. First, a preform of hot plastic resin in a somewhat tubular/bowl shape is created. Then, a pressurized gas, usually air, is used to expand the hot pre-form and press/suck it against a mold cavity.

B) Secondary Shaping Process Chip Removing Process/ Machining

Turning

Facing Grooving

Drilling is a cutting process that uses a drill bit to cut or enlarge a hole in solid materials. The drill bit is a multipoint, end cutting tool. It cuts by applying pressure and rotation to the work piece, which forms chips at the cutting edge

Drilling Shaping is used to machine flat or plane surfaces in horizontal and angular planes.

Shaping

Knurling

Boring is a cutting operation that uses a single-point cutting tool or a boring head to produce conical or cylindrical surfaces by enlarging an existing opening in a work piece

Boring Slotting is used to machine flat or plane surface in vertical planes. It is mainly used for internal machining of blind holes of vertical machining of complicated shapes wich are difficult to produce on shaping machine

Slotting

Threading

Planing is a cutting process that uses a cutting tool in stationary position with rotation and job in motion. It is best suited for large work pieces to get the geometrical accuracy.

Planing

Broaching is a machining process that uses a toothed tool, called a broach, to remove material. There are two main types of broaching: linear and rotary. In linear broaching, which is the more common process, the broach is run linearly against a surface of the work piece to affect the cut

Broaching Grinding is an abrasive machining process that uses a grinding wheel as the cutting tool.

Grinding Chamfering is an operation of beveling the extreme end of the work piece. Chamfer is provided for better look, to remove burrs and protect the end of the work piece from being damaged.

Chamfering

Milling

Milling is the process of removing metal by feeding the work past a rotating multipoint cutter. In milling operation the rate of metal removal is rapid as the cutter rotates at a high speed and has many cutting edges. Thus the job are machines at a faster rate than with single point tool and the surface is also better dur to multicutting edges.

Forming Process (hot & cold) Coining Bending Rolling Drawing Spinning

Sheet metal operations Shearing: – – – – – – – – – –

Piercing. Producing noncircular holes Punching. Producing circular holes (punched out is waste) Perforating. Number of small holes near to each other Blanking. Blank sheet to desired shape. (blanked out is required part) Cutting off. Removing a piece from sheet along a line (a,b,c) Parting. Removal of scrap between two work pieces/ parting line. Notching. Removal of small material from side or edge (d) Slitting. Cutting in a line along the length (e) Lancing. Bending one side after cutting other sides (f) Trimming. Removing excess material around the parting line

2. Bending: – – – –

Angle bending. Curling. Forming. Plunging.

C) Surface Finish Process: • Grinding: • Polishing: Precision metal remaking, to remove scratches & minor surface imperfections, abrasive particles are used. • Buffing: To bring maximum luster, before plating & after polishing. • Honning: Circular holes. • Lapping: Geometrically true surface, very close fit between two surfaces. • Electro Plating • Metal Spraying

D) ing Process: • Welding > 450°C (840ºF) • Soldering < 450°C • Brazing ≥ 450°C • Riveting • Screw Fastening • Pressing • Adhesive ing • Interlocking • Stretching • Knotting (appliqué)

E) Processes Effecting Change in Properties: • Heat Treatment: annealing, hardening, tempering. Shotpeaning, • Shot Penning

Surface Finish Notations

8.25 µ

• Turning • Milling • Planning & Shaping • Drilling

1.6 – 8 µ

• Planning & Shaping • Drilling • Boring • Milling • Forging

0.025 – 1.6 µ

• • • • •

Grinding Boring Milling Turning Reaming

< 0.025 µ

• Lapping • Honing