PROCESS OF SEAT PIPE PRODUCTION FROM SOLID METAL COIL
THROUGH COLD EXTRUSION OPERATION
Field of the present Invention:
The present invention relates to a process of seat pipe production by cold
extrusion operations, particularly in continuous manner in automation, from the
solid metal coil received as the raw material for the purpose. Towards the
proposed manufacturing of the seat pipe, the cold extrusion operations are
strategically performed on the solid cylindrical piece of billet, freshly cut from the
metallic coil received, preferably in multiple steps, using suitable multiple set(s) of
dies. After completion of the extrusion operations, other machining steps are
performed according to certain specific plan towards strengthening the product,
structural refinement and functionality improvement.
Background and obiect of the present invention:
Seat pipes are very important parts used in automobiles particularly in power
generation/transmission. The seat pipe is a sophisticated device which requires
perfect structural features and enough structural strength for its effective
functioning. Therefore, one conventional method used for manufacturing seat
pipes involves forging which may has its own merits, but it is a very time taking
process. The raw material used in this process is usually a hollow piece of
metallic tube, kept at certain elevated temperature range, but below the
recrystallization temperature of the material. Trimming is used when a forming
operation leaves material in the form of flash around the edges of the part. The
forging process is comparatively an expensive process. The product
manufactured by such conventional process, includes:
• Lesser tolerance,
• Warping of material during the cooling process ,
• Undesirable result due to reaction of metal with that of surroundings ,
• Varied metal structure,
• High loss of materials etc.
Cold forging involves complex mechanism and resources, heavier and more
powerful equipments, and much skilled man power and specific environment for
the operations. The strong tooling is also required. The quality of forged product
further depends on:
•^ Forging conditions, like temperature, pressure, horizontal/ vertical
position;
^ Die quality, its strength, its material and finishing, etc.;
^ No. of steps involved in the forging and thus the no. of sets of dies.
The forging is a more difficult and time consuming process than the extrusion,
but it yields a product with all needful structural and functional features. So
depending upon the specific needs and use of product being manufactured, the
process of manufacturing should be chosen to be economical. Forging requires
more efforts and cost than extrusion.
Use of extrusion operation as the main step towards the manufacturing of the
seat pipe, as proposed herein, is not known. One of the main reasons is nonachievement
of various technical parameters required for such extrusion, mainly
during performing the cold extrusion operation on the solid piece of cylindrical
shaped metallic billet. So the process described herein the present invention is
better in terms of cost and efforts required. Proposing the use of continuous and
automated cold extrusion operations towards converting a solid cylindrical piece
of metal into a desired hollow seat pipe with all needful structural features,
including its head section is a unique and very economical development.
Present invention involves cold extrusion operation on a solid piece of billet,
directly cut afresh during the process from the solid metallic coil in continuous
manner, wherein the cold drawn solid coil is received by the cold extrusion
former machine. Such cold extrusion of the solid metallic billet into the desired
seat pipe is produced in multiple steps during continuous cold extrusion steps
performed on the cold former. The multi cold extrusion operations are
strategically performed on horizontal press-stations of the cold former in
continuous stepwise manner, wherein the work-piece for extrusion operations is
obtained during the process itself from the cold drawn solid coil, straightened
and received by the cold extrusion former machine. Separate sets of dies at
separate press-stations are engaged for performing multi step cold extrusion
operations towards producing the desired seal pipe.
The main objective of the present invention is to propose a process of seat
pipe production by cold extrusion operations, particularly in continuous manner in
automation, from the solid metal coil received as the raw material for the
purpose.
Another prime object of the present invention is to propose an optional
scheme for the process of manufacturing of the seat pipe using the solid metallic
coil as raw material, wherein the cold extrusion operations are strategically
performed in continuous stepwise manner on the solid cylindrical piece of billet,
freshly cut during the process from the metallic coil received, preferably using
different and separate sets of dies at separate press-stations.
Another object of the present invention is to propose a cold extrusion method
in automation for creating a hollow cylindrical piece of seat pipe with a head
section, having hexagonal surface-profile at its inner side; wherein the whole seat
pipe component and its head section is created from the solid piece of metallic
billet freshly cut from the metallic coil, received as raw material.
Another object of the present invention is to propose further set of operations
after completion of the extrusion steps, wherein such secondary machining steps
are performed according to certain specific plan towards strengthening the
product, structural refinement and functionality improvement.
Another object of the present invention is to propose a process of seat pipe
production, wherein raw material used is simply the sold metallic rod of certain
diameter, which is received as the coil of that metallic rod and is directly fed to
the automatic work-piece making-cum-processing installation towards its
straightening, billet cutting and forwarding towards other continuous extrusion
press-stations thereof.
Another object of the present invention is to propose a process of seat pipe
production in continuous cold extrusion operations, wherein such operations are
preferentially performed in continuous steps on the work-piece, getting
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transferred in stepwise manner on the multiple press-stations on the continuous
horizontal hydraulic press installation, using different set of close dies therein.
Another object of the present invention is to propose a process of seat pipe
production in continuous cold extrusion operations, wherein multiple sets of dies
are designed and installed with the press-stations of the horizontal cold extrusion
former installation, wherein preferably three to five sets of such die sets are
installed on three to five press-stations for performing cold extrusion operations
on the solid metallic billet generated during the process for desired seat pipe
making, as described herein.
Another object of the present invention is to eliminate the billet formation step,
before subjecting the raw material to cold extrusion steps towards production of
the seat pipe with desired structural and functional features.
Another object of the present invention is to propose a novel process of seat
pipe production with all necessary structural and functional features, which is less
resource consuming, much economical and considerably enhances the
production rate.
Statement of the present invention:
The present invention is intended to propose:
• A process of seat pipe production by cold extrusion operations,
particularly in continuous manner in automation, from the solid metal
coil received as the raw material for the purpose;
• An optional scheme for the process of manufacturing of the seat pipe
using the solid metallic coil as raw material, wherein the cold extrusion
w
operations are strategically performed in continuous stepwise manner
on the solid cylindrical piece of billet, freshly cut during the process
from the metallic coil received, preferably using different and separate
sets of dies at separate press-stations;
• A cold extrusion method in automation for creating a hollow cylindrical
piece of seat pipe with a head section, having hexagonal surfaceprofile
at its inner side; wherein the whole seat pipe component and its
head section is created from the solid piece of metallic billet freshly cut
from the metallic coil, received as raw material;
• Certain set of operations after completion of the extrusion steps,
wherein such secondary machining steps are performed according to
certain specific plan towards strengthening the product, structural
refinement and functionality improvement;
• A process of seat pipe production, wherein raw material used is simply
the sold metallic rod of certain diameter, which is received as the coil
of that metallic rod and is directly fed to the automatic work-piece
making-cum-processing installation towards its straightening, billet
cutting and forwarding towards other continuous extrusion pressstations
thereof;
• A process of seat pipe production in continuous cold extrusion
operations, wherein such operations are preferentially performed in
continuous steps on the work-piece, getting transferred in stepwise
Hmanner
on the multiple press-stations on the continuous horizontal
hydraulic press installation, using different set of close dies therein;
• A process of seat pipe production in continuous cold extrusion
operations, wherein multiple sets of dies are designed and installed
with the press-stations of the horizontal cold extrusion former
installation, wherein preferably three to five sets of such die sets are
installed on three to five press-stations for performing cold extrusion
operations on the solid metallic billet generated during the process for
desired seat pipe making, as described herein;
• To eliminate the billet formation step, before subjecting the raw
material to cold extrusion steps towards production of the seat pipe
with desired structural and functional features; and
• A novel process of seat pipe production with all necessary structural
and functional features, which is less resource consuming, much
economical and considerably enhances the production rate.
Short description of the present invention:
The present invention generally describes a process of producing seat pipe from
the solid metal coil of certain diameter as raw material, wherein said raw material
is fed to the multi-station cold extrusion former installation, preferably the
horizontal cold former where a series of cold extrusion operations are performed
on more than one cold extrusion press-stations engaging die-sets of
corresponding work-piece extruded. Thus through proposed multiple cold
extrusion operations, which are being performed simultaneously, continuously in
^
automation on the multiple press-stations of the cold former installation, the
desired seat pipe with all basic structural and functional features, including its
head section, containing its hexagonal inner surface profile, is created, which is
subjected to other secondary set of mechanical operations towards surface
refining and product finishing in stepwise manner. Such stepwise operations are
pre-machining, CNC-1 and 2, cross hole drilling, hole drilling, thread tapping,
deburring, centreless grinding, washing, oiling and packing.
The process of manufacturing follows mainly four steps,
i. Cold Extrusion for basic dimension of seat pipe,
ii. Cold Extrusion for Hex formation
iii. CNC machining
iv. Finishing and other process.
The schematic plan for performing the proposed complete process herein is
illustrated in the schematic flow chart diagram of Figure 1.
The coil of solid metal is fed to the multi-station cold former installation. Said
coil of solid metal is preferably the high quality steel, specific to the structure and
function of the final component being produced herein. Actually the present
invention is an effort to utilize the solid metallic coil of certain diameter as such,
which was conventionally being used by the automobile and engine component
manufacturing companies for billet formation. Thus the proposed invention
eliminates the billet formation step and proposes to directly mount the solid coil
received as the raw material to the cold extrusion former installation. Said solid
coil is straightened and driven to the first work station of cold extrusion former by
the feed roller, wherein a suitable length from said solid coil is cut and is
>r
immediately transferred to another work-station therein for continuous cold
extrusion operations, involving suitable means for the same, such as cam
arrangements and/or transfer fingers. Such cam arrangements and/or transfer
fingers shift the work-piece from one press-station to the next one, after
completion of every extrusion stroke therein. Thus, the solid metallic work-piece
is preferably subjected to multiple cold extrusion operations one after another on
continuous press-stations therein, engaging corresponding sets of dies at those
press-stations. Thus the initial piece of solid metallic work-piece, cut from the
straightened solid coil, receives cold extrusion treatments in multiple steps,
preferably three to five steps, particularly keeping the extent of high abrasion and
extent of structural distortion/modification pattern upto internal metallic structure
therein. These forceful structural modification in the dimension of solid cylindrical
piece of metal through continuous cold extrusion steps, particularly on horizontal
hydraulic multiple press-stations, are optimized and performed at certain specific
parameters, namely pressure, rate of stroke per unit time, die-set structure profile
etc. in such a manner to yield error free intermediate work-piece(s) and/or the
finally extruded seat-pipe with desired shape and dimension. The complete
extrusion operations are continuous and automated with the involvement of
certain software based or logic based control-mechanism, so that uniform and
best optimized operations are performed.
During the cold extrusion operations the solid cylindrical piece of metal is
preferably extruded to pre-determined length and to create certain depressions
from both ends towards making a tube in next steps. In next steps said extruded
work piece is further extruded to create the seat pipe of desired dimension,
including the creation of the head section, wherein the inner region/surface of the
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head section is shaped uniquely as a hexagon. All such structural features and
the shape/dimensions of the seat pipe product are achieved through effective
multiple cold extrusion operations, performed in continuous and stepwise
manner.
Pre machining is the term related to the pre inspection of quality and capacity
of machine and product before CNC process.
CNC Machining is a process that involves the use of computers to control
machine tools. Tools that can be controlled in this manner include lathes, mills,
routers and grinders. CNC Machining stands for Computer Numerical Control.
The process is more precise than manual machining, and can be repeated in
exactly in the same manner over and over again. Because of the precision
possible with CNC Machining, this process can produce complex shapes that
would be almost impossible to achieve with manual machining. After completion
of cold extrusion operations, the unfinished and extruded seat pipe components
are subjected to CNC-1 (Tap side M/cng) followed by CNC-2 (hexagonal head
section M/cng).
After CNC machining, cross hole drilling is done. Drilling is a cutting process
that uses a drill bit to cut or enlarge a hole of circular cross-section in solid
materials. The process of cutting threads that means the irregularities in the
shape, using a tap is called tapping, whereas the process is called threading.
And this whole process is called Thread tapping.
Deburring is the most important process in finishing of the product. Metal is
frequently machined using many processes in order to create pieces of specific
shape and size, and it may be welded, molded, cast, trimmed, slit or sheared.
These procedures often create ragged edges or protrusions. The raised particles
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and shavings that appear when metal blanks are machined are referred to as
burrs, and the process by which they are removed is known as deburring.
After deburring, Centreless Grinding to the said seat pipe component is
performed. Centerless grinding is a machining process that uses abrasive
cutting to remove material from a work-piece. Centerless grinding differs from
centered grinding operations, in that no spindle or fixture is used to locate and
secure the work-piece.
After these finishing processes the product is washed and then the final
inspection takes place. Then the oiling of the product is done before its packing.
The schematic view of the solid metallic piece, cut from the solid metal coil and
the seat pipe as the final product are shown in Figure 2 hereinbelow.
Scope of the invention:
Although the invention has been described with reference to specific
embodiments, this description is not meant to be construed in a limiting sense.
Various modifications of the disclosed embodiments, as well as alternate
embodiments of the invention, will become apparent to persons skilled in the art
upon reference to the description of the invention. It is therefore contemplated
that such modifications can be made without departing from the spirit or scope of
the present invention as defined.
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1. Process of seat pipe production from solid metal coil through cold extrusion
operations, particularly in continuous manner in automation, followed by the
performing secondary operations towards refining and finishing the product.
2. Process of seat pipe production from solid metal coil through cold extrusion
operations, as claimed in claiml, wherein said process is characterized by use of
the solid metallic coil as raw material received, wherein the cold extrusion
operations are strategically performed in continuous stepwise manner on the
solid cylindrical piece of billet, freshly cut during the process from the metallic coil
received, preferably using different and separate sets of dies at separate pressstations.
3. Process of seat pipe production from solid metal coil through cold extrusion
operations, as claimed in claim 1, wherein said process involves cold extrusion
operations in automation for creating a hollow cylindrical piece of seat pipe with a
head section, having hexagonal surface-profile at its inner side; wherein the
whole seat pipe component and its head section is created from the solid piece
of metallic billet, freshly cut from the metallic coil, received as raw material.
4. Process of seat pipe production from solid metal coil through cold extrusion
operations, as claimed in claim 1, wherein after completion of cold extrusion
operations towards seat pipe preparation, further set of operations, namely premachining,
CNC-1 and 2, cross hole drilling, hole drilling, thread tapping,
deburring, centreless grinding, washing and oiling are performed, wherein such
set of secondary machining steps are characterized by their selection.
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optimization and performance towards strengthening the product, structural
refinement and functionality improvement therein.
5. Process of seat pipe production from solid metal coil through cold extrusion
operations, as claimed in claim 1, wherein the sold metallic rod of certain
diameter is straightened and driven to the first work station of cold extrusion
former by the feed roller, wherein a suitable length from said solid coil is cut and
is immediately transferred to another work-station therein for continuous cold
extrusion operations, involving suitable means for the same, such as cam
arrangements and/or transfer fingers.
6. Process of seat pipe production from solid metal coil through cold extrusion
operations, as claimed in claim 1, wherein said the solid metallic work-piece is
preferably subjected to multiple cold extrusion operations one after another on
continuous press-stations therein, engaging corresponding sets of dies at those
press-stations.
7. Process of seat pipe production from solid metal coil through cold extrusion
operations, as claimed in claim 1, wherein said continuous and multiple steps of
cold extrusion operations are characterized by multiple sets of dies, designed
and installed with the press-stations of the horizontal cold extrusion former
installation, wherein preferably three to five sets of such die sets are installed on
three to five press-stations for performing cold extrusion operations on said solid
metallic billet generated during the process for desired seat pipe making.
8. Process of seat pipe production from solid metal coil through cold extrusion
operations, as claimed in claim 1, wherein the proposed process is characterized
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12 NOV 20«
by elimination of separate billet formation step before subjecting the raw material
to cold extrusion steps towards production of the seat pipe.
9. Process of seat pipe production from solid metal coil through cold extrusion
operations, as claimed in claim 1, wherein the solid cylindrical piece of metal is
preferably extruded to pre-determined length with depressions from both ends
towards making a tube and in next steps said extruded work piece is further
extruded to create the seat pipe of desired dimension, including the creation of
the head section, wherein the inner region/surface of the head section is shaped
uniquely as a hexagon.
10. The seat pipe, as produced by the said process of seat pipe production
from solid metal coil through cold extrusion operations, as claimed in claim 1.