Introduction
It is known
that the metals are found in nature forming elements combined with other
minerals. To use them as beams, to make specific parts of machines, or any
other use, you must:
Insulating
material accompanying elements.
Send as
required in each case so that it can fulfill the mission that man throws at
you.
The first
goal is achieved by so-called metallurgical operations.
The
metallurgy studies the processes that allow benefit minerals and metals
extracted from them.
Processes of forming of metals
Comprise a
varied set of operations by which changes the shape and dimensions of the
metals to make those needed to adopt for each specific use. For each of these
operations, the man used tools and machines.
Forming
processes can be divided into major groups, which are:
1.For foundry
Consists of
filling with molten metal from a vessel (mold) having a hole whose shape and
dimensions are similar to those of the piece to be obtained.
This
procedure can be obtained very complicated shaped parts. Metals must be used
very well fluid to fill the voids of the mold.
2.Deformation hot
Consists
shocks or deform by compression continued efforts a piece of metal preheated
until it is the shape and precise dimensions. These processes include:
- Forge: It consists in deforming by hitting either by hand or with mechanical hammer a piece of metal heated to change its shape or dimensions. Iron and other products derived from it are forged well.
- Hot rolling:It consists
of a heated metal deformed by passing between two cylinders that exert
continuous pressure on him.
The process
is used for thick plates or bars certain profile. For the preparation of the
thin plate in cold
rolling is performed.
- Hot stamping: Involves
pressing between two metal molds (dies) a piece of material at the right
temperature until strain filled the gap between them, taking their form which
is naturally the piece to be obtained. The two prints are pressed by a powerful
press.
- Hot extrusion:Consists in
deforming a heated metal, forcing it to pass through a hole (row) having the
shape and dimensions desired for the bar or profiles to obtain. This process is
used primarily for soft metals such as zinc, copper, aluminum, etc..
3.Deformation cold
When
dealing with very thin parts or materials sides, some deformation processes
described above such as rolling, deformation stroke, etc. Are performed without
heating the material. Among the cold deformation process can include:
- Punching: is to obtain
pieces torn from a sheet by shear between a punch and a die whose shape
coincides with the parts you want to retrieve.
- Drawing: This
process achieves a thin sheet, how to take that force two pieces (punch and
die) by pressing on it. They are used to obtain hollow metal.
4.Forming processes in metal cutting:Machining
Is to reduce
the size of a piece of material and change its shape by starting up small
pieces of chips using special tools provided with edge. Different metal removal
processes differ mainly in the type of tools and the way it moves and the
workpiece relative to one another to achieve the intended effect of metal
removal. We will mention some of these processes:
- Serrated: This
operation aims to chop the material: it can be done in special machines or by
hand.
- The filing: Is a manual
operation is performed with a tool called lime and designed to change the shape
or surface condition of a small piece by starting chips tiny teeth are cut by
the tool has cut in its surface.
- Chiselling: The carving
is an operation which consists of starting material or separate pieces of parts
of it using a tool provided with prismatic edge, which is struck at the
opposite end to it with a hammer.
5.Chip boot process using machines
- Dividing up: A tool,
equipped with reciprocating workpiece material starts career advancement
(colored arrow). When the tool withdraws, the piece is moved to the next race
in the tool find new material to cut.
- Turning: It is an
operation designed to work cylindrical bodies. The clamped workpiece in the
machine head rotates on its axis while the tool moves (arrow color) starts the
outside material.
- Milling: A method of
machining flat surfaces or of specially shaped blades by multiple tools which
rotate about their axis removing material from the workpiece when it comes
close.
- Drilling: This
operation aims to make cylindrical holes in the pieces. A tool (drill) which is
provided with helical cutting edges. The drill bit rotates about its axis and
penetrate the chips tearing piece goes out through channels carved into the
drill body.
6.Union of metal parts welding
This operation
is solidly join two metal parts by elevating the temperature of the surfaces to
be welded and providing the same or different substances to the welded nature.
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