BLANKING:

Blanking is the operation of cutting a flat shape from sheetmetal . The part punched out from the metal strip is called “blank”, and it is the required product of the operations. It is usually the first step of series of operations. After blank the metal strip called as scrap.

PIERCING (OR) PUNCHING

Piercing is the operation of producing a circular or other contour shape hole in a sheet metal. The pierced out of the metal is called slug or scrap.


CUTTING OFF:

Cutting off is the operation of cutting apiece from the sheet metal. The cut is madealong a straight line or a curved line.in cutting off operation,there is no scrap.
In this operation, upper blade(punch) is connected to the ram. Lower blade is fixed in machine frame. The work is placed between two blades. A slight clearance between the cutting edges of blades. When the upper blade moves it cuts off the sheet metal

PARTING OFF:

Parting is the operation cutting the sheet metal pieces.Three blades are used in thisoperation. There are two lower blades fixed to themachine frame. The upper blade is connected to theram. Agap is provided between two lower blades, the gap can be adjusted. This gap depends upon the thickness of sheet metal. The upper blade movesdown and cuts the sheet metal. Some scrap is removed in this operation.

NOTCHING:

Notching is the cutting operation by which metal pieces are cut from the edge of a sheet.

SLITTING:

Slitting is the operation, cutting a sheet metal in a straight line. The cut takes place along the length of sheet metal

LANCING:

Lancing is the operation of cutting a sheet metal through a small length and than bending the cut portion. It does not produce a detached slug and leaves a bent portion attached to the work material.

Example: Mosquito coil stand.

PEFORATING:

In this process,multiple holes are produced, which are very small and close together are cut in flat work material.

BENDING:

Bending is a non cutting opration. In bending,the straight of the sheet metal is bent to a curved length. It is a very common forming process for changing sheet into channels, drums,tanks etc.

During the bending operation, the outer surface of the metal is in tension and the inside surface is in compression. The strain in the bent material increases with decreasing radius of curvature. The stretching of the bend causes the neutral axis of the section to move towards the inner surface.

V-BENDING (OR) ANGLE BENDING

It is the operation bending a sheet metal to a sharp acute, 90 degree or obtuse angles.The punch and die are shaped. The angle of punch and die is selected taking into account the spring back of the sheet metal.

EDGE BENDING


In edge bending, a flat punch forces the metal against the vertical face of the die. The bend axis is parallel to the edge of the die and the stock is subjected to cantilever loading. In this bending, a pressure pad is used, for prevent the movement of the stock during operations.

SHAVING

TRIMMING

This operation is similar to shaving operation.This operation consists of cutting excess material from the periphery of a formed part

CURLING

Curling is the operation of rolling the edges of the sheet metal to a small circular form. Curling is done to strengthen the edges. By curling, the sharp edges of the metal is avoided.

The lower die held stationary. The upper die has got a curved form at its end. When it moves down,the edge of the work is curled into a circle. Curling is used in making sheet metal vessals and containers

FORMING


COINING

Coining is the operation of squeezing the metal between two dies. A blank of correct size is placed between the lower and upper die.Both dies are engraved to have the required pattern and shape.

Both the dies press the metal blank with very high force. The blank metal flows in the cold state and fills up the cavity between the dies. The pattern on the two dies are transferred to the component.The movement of the die is guided by a guide plate.These operations producing coins,metal and other similar parts.

EMBOSSING

Embossing is the operation of giving impressions of letters, figures or patterns in sheet metal parts.
The blank is placed between two dies. The dies will have the same Impression for the required component. One die have projection and the other die have corresponding depressions. The upper die presses down the blank on the lower die. The blank metal flows in the cold state and gets the required impressions.

These operations is used on tin containers, covers and name plates.

PLUNGING

Plunging is the operation of localized bending around a hole in the sheet metal. Plunging is done in two stages. First the hole is pierced in the work at the required position using piercing punch and die. Then the hole in the sheet metal is plunged The plunged hole will take the shape of the punch and die. Plunging is done to received a screw head or rod through the holes. Plungingaremade asCountersunk, burred or dimpled holes.Plunging operation is also called as Hole flanging or Extruding.

FLATTENING OR PLANISHING

This is the operation of straightening a bent or curved sheet metal. The planishing punch has small projections on its face. The projections are spaced equally. The die has a flat plain surface.The sheet metal having bent is placed over the flat die. The punch presses the sheet metal with high pressure.The bends on the sheet metal are removed.

DRAWING OR CUPPING

Drawing is the operation of producing cup shaped parts from the sheet metal blanks. The blank is placed over the forming die. The stripper plate is hold the blank on the die. When the punch moves down, the blank is pushed into the dieopening. A pressure pad is placed inside the die opening, which is used for uniform drawing operation.Plastic deformation takes place in the blank. The metal is drawn over the surface of the die opening. Sufficient clearance is given between the punch and die.A cup shaped components are produced by drawing operation,this process is calledCupping.

DEEP DRAWING

Deep drawing is the operation of producing cup shaped components having more depth. Here the depth of the component produced is more than its diameter.
Deep drawing is done in different stages,by using different sets of punch and dies. After each stage of drawing, the blank surface gets hardened. So to avoid rupture and failure, the blank is annealed before the next stage of drawing operations.