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WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING (operations of the kind involved in the manufacture of such products B21B, B21C; working or processing of wire B21F; cutting or severing devices or machines in general B26; presses in general B30B)
Definition statement
This subclass/group covers:

Processes and apparatus for the mechanical working of sheet metal or metal tubes, rods or profiles without essentially removing material.

Processes and apparatus for punching, i.e. press-cutting, sheet metal or other metal stock material, as a particular mechanical working which removes material.

It further covers the following parts and devices related to those apparatus:

Tools as parts of those machines;

Feeding, positioning or storing devices combined with, or arranged in, or specially adapted for use in connection with, those apparatus;

Ejecting or stripping-off devices arranged in those machines or tools;

Associations of cutting devices with those apparatus;

Special measures to adapt those apparatus for working metal foils, e.g. gold foils;

Safety devices protecting the machine or the operator, specially adapted for those apparatus.

The mechanical working covers treatments characterised by their function, comprising methods for

straightening, restoring form or removing local distortions,

bending or twisting,

corrugating, bending into wave form or forming single grooves,

edge treatments, e.g. for flanging tubes

shaping without cutting by stamping, spinning, deep-drawing or by applying fluid pressure or magnetic forces,

shaping by press cutting, i.e. punching, e.g. for cutting-out or perforating,

stretching sheet metal of limited length,

stabbing, piercing, expanding, hammering, beating, peen forming or other methods,

processes combining those methods.

The processing of sheet metal or metal tubes, rods or profiles covers the application of those mechanical metal-working treatments or methods for the following particular purposes

in order to connect objects or parts,

in order to expand tubes,

in order to alter the diameter of tube ends,

in the manufacture of finished or semi-finished articles, comprising rigid structural elements or units, hollow objects and other particular articles,

for sheathing or stiffening objects.

Relationship between large subject matter areas

Input products

B21B covers rolling of metal. B21C covers the manufacture of metal sheets, rods, tubes, profiles or like semi-manufactured products otherwise than by rolling. Operations of the kind involved in the manufacture of metal sheets or metal tubes, rods or profiles are therefore covered by subclasses B21B and B21C. However, the semi-finished products manufactured by the operations of B21B (e.g. sheet metal coils, tubes, profiles) or B21C (e.g. tubes, concrete rods, profiles) may be input products for the metal-working and processing covered by B21D as for example straightening, bending, corrugating, forming single grooves, flanging or edge treatment, shaping by stamping, spinning or deep-drawing, stretching, press-cutting or perforating.

The mechanical working of wire, which is a further semi-finished product manufactured by the operations of B21C, is covered by the specific subclass B21F.

The mechanical working of metal foils in a manner analogous to the working of paper is covered by B31F, except for the perforating, cutting, or otherwise severing, of metal foils, which is covered by B26D and B26F. Other special measures in connection with working metal foils, e.g. for adapting apparatus of B21D therefore, are covered by main group B21D 33/00.

Presses

Presses in general, e.g. characterised by their pressing member or the drive there for, and details thereof, or accessories there for (e.g. the construction of the frame or control arrangements) are covered by B30B. The special adaptation of presses for the purposes of stamping, deep-drawing or punching sheet metal or metal tubes, rods or profiles is covered by B21D, especially by main group B21D 24/00 for special deep-drawing arrangements in, or in connection with, presses.

References relevant to classification in this subclass
This subclass/group does not cover:
Working or processing of wire, e.g. for making wire fabrics
Making nails, pins or the like by cutting from strips or sheet material
Making chains or chain parts
Informative references
Attention is drawn to the following places, which may be of interest for search:
Rolling of metal in general
Manufacture of metal sheets, rods, tubes, profiles or like semi-manufactured products otherwise than by rolling; Auxiliary operations used in connection with metal-working operations without essentially removing material
Forging; Hammering; Pressing; Riveting
Making forged or pressed products
Working metal by removing material there from
Shearing or similar cutting of metal, e.g. tubes or profiles
Other working of metal; Combined Operations; Universal machine tools
Features of cutting or severing devices or machines in general
B26
Presses in general, e.g. safety devices there for
Safety devices in general
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Profile
a load supporting metal bar with a particular cross section different from those of tubes or rods, e.g. an I-beam
Straightening, restoring form or removing local distortions of sheet metal or specific articles made therefrom ( B21D 3/00 takes precedence) ; Stretching sheet metal combined with rolling (working sheet metal of limited length by stretching B21D 25/00 ; by localised hammering B21D 31/06 )
Definition statement
This subclass/group covers:

All aspects related to straightening, restoring form or removing local distortions of sheet metal or specific articles made therefrom (e.g. straightening uncoiled bands or strips, removing bumps in sheet metal structures like cars, airplanes, etc ... , straightening structures, e.g, crashed vehicle bodies).

References relevant to classification in this group
This subclass/group does not cover:
Working sheet metal of limited length by stretching
Working sheet metal of limited length by localised hammering
Flattening hollow objects for transport and reforming
Informative references
Attention is drawn to the following places, which may be of interest for search:
Servicing, repairing vehicles
Straightening or restoring form of metal rods, metal tubes, metal profiles, or specific articles made therefrom, whether or not in combination with sheet metal parts (straightening of well casings in situ E21B )
Definition statement
This subclass/group covers:

All aspects related to straightening or restoring form of metal rods, metal tubes, metal profiles and specific articles made therefrom, whether or not in combination with sheet metal parts (e.g crankshafts).

References relevant to classification in this group
This subclass/group does not cover:
Straightening by twisting only

Places where the subject matter of this group is covered when specially adapted, used for a particular purpose, or incorporated into a larger system:

Straightening rails or rail joints
Straightening of well casings in situ
Informative references
Attention is drawn to the following places, which may be of interest for search:
Repairing methods or devices of turbine blades
Bending sheet metal along straight lines, e.g. to form simple curves ( B21D 11/06 to B21D 11/18 take precedence; corrugating sheet metal B21D 13/00 ; as edge treatment B21D 19/00 )
Definition statement
This subclass/group covers:

Methods and devices for bending sheet metal along straight lines

References relevant to classification in this group
This subclass/group does not cover:
Corrugating sheet metal
Bending sheet metal as edge treatment

Places where the subject matter of this subclass group) is covered when specially adapted, used for a particular purpose, or incorporated into a larger system:

Manufacture of tubes or metal hoses by bending sheet metal
Informative references
Attention is drawn to the following places, which may be of interest for search:
Bending of plastics
Bending rods, profiles, or tubes ( B21D 11/02 to B21D 11/18 take precedence; using mandrels or the like B21D 9/00 )
Definition statement
This subclass/group covers:
Methods and devices for bending metal rods, profiles or tubes.
References relevant to classification in this group
This subclass/group does not cover:
Corrugating tubes by bending
Bending tubes or profiles as edge treatment
Bending tubes using mandrels or the like
Informative references
Attention is drawn to the following places, which may be of interest for search:
Bending of plastics
Working and processing of wire
Bending tubes using mandrels or the like ( B21D 11/02 to B21D 11/18 take precedence)
Definition statement
This subclass/group covers:

Methods and devices for bending tubes using mandrels or the like.

The group also covers the bending mandrels as such.

Mandrels are used to keep the cross sectional shape of the tube in the bending area (i.e. to avoid unwanted deformations).

References relevant to classification in this group
This subclass/group does not cover:
Corrugating tubes by bending
Bending tubes as edge treatment
Bending not restricted to forms of material mentioned in only one of groups B21D 5/00 , B21D 7/00 , B21D 9/00 ; Bending not provided for in groups B21D 5/00 to B21D 9/00 (corrugating or bending into wave form B21D 13/00 , B21D 15/00 ; flanging B21D 19/00 ) ; Twisting
Definition statement
This subclass/group covers:

Methods and devices for bending not restricted to either sheet metal, tubes, rods or profiles. This covers:

Bending by stretching or pulling over a die

Bending into special geometrical forms, e.g: helical, spiral, serpentine

Bending by altering the thickness of part of the cross-section of the work

Bending specially adapted to produce specific articles, e.g. leaf springs, reinforcements for concrete

Twisting

Joggling

Special bending methods and devices not covered by other subgroups in B21D

Auxiliary bending equipment, e.g. positioning devices, heating devices

References relevant to classification in this group
This subclass/group does not cover:
Bending sheet metal along straight lines
Bending rods, profiles, or tubes
Bending tubes using mandrels or the like
Corrugating or bending into wave form
Flanging
Working sheet metal of limited length by stretching

Places where the subject matter of this subclass group) is covered when specially adapted, used for a particular purpose, or incorporated into a larger system:

Making leaf springs by bending
Processes for producing ornamental structures by bending
Corrugating sheet metal, rods or profiles; Bending sheet metal, rods or profiles into wave form (tubes B21D 15/00 )
Definition statement
This subclass/group covers:

Methods and devices for corrugating or bending into wave form of sheet metal, rods or profiles. Corrugating here also means forming embossments/dimples all over the surface of a metal sheet.

References relevant to classification in this group
This subclass/group does not cover:
Corrugating tubes by bending

Places where the subject matter of this subclass group) is covered when specially adapted, used for a particular purpose, or incorporated into a larger system:

Machines or apparatus for embossing decorations or marks in sheet metal
Pressing or stamping ornamental designs on surfaces of sheet metal
Corrugating tubes (wrinkle-bending using mandrels or the like B21D 9/14 )
Definition statement
This subclass/group covers:

Methods and devices for corrugating or bending into wave form of tubes.

References relevant to classification in this group
This subclass/group does not cover:
Wrinkle-bending using mandrels or the like

Places where the subject matter of this subclass group) is covered when specially adapted, used for a particular purpose, or incorporated into a larger system:

Corrugating tubes annularly with thinning
Forming single grooves in sheet metal or tubular or hollow articles
Definition statement
This subclass/group covers:

Forming grooves by deformation of the sheet only, without variation of the thickness (i.e. the grooves are not obtained by crushing the metal).

Informative references
Attention is drawn to the following places, which may be of interest for search:
Grooving or notching of bolts, studs or the like
Flanging or other edge treatment, e.g. of tubes (connecting by making use of folds B21D 39/00 ; flaring-out tube ends B21D 41/02 )
Definition statement
This subclass/group covers:

Methods and devices for applying flanges on edges or holes of metal sheets or tubes.

Edge treatments like edge deburring or smoothing by sheet metal working techniques without removing material

References relevant to classification in this group
This subclass/group does not cover:
Connecting by making use of folds
Flaring-out tube ends
Informative references
Attention is drawn to the following places, which may be of interest for search:
Chamfering or deburring the ends of tubes
Combined processes according to methods covered by groups B21D 1/00 to B21D 19/00
Definition statement
This subclass/group covers:

Processes combining two or more metal working methods from the following list:

Strai ghtening,

bending,

corrugating,

forming single grooves,

flanging or other edge treatment.

Shaping without cutting, by stamping, spinning, or deep-drawing (otherwise than using rigid devices or tools or yieldable or resilient pads B21D 26/00 )
Definition statement
This subclass/group covers:

All kinds of methods and devices for shaping sheet metal or tubes by

Stamping using rigid devices or tools: the sheet stock is shaped between a punch and a die.

Stamping using yieldable or resilient pads: the shaping member is yieldable or resilient and is forced against the sheet stock; there may be a die against which the sheet stock is pressed, but not necessarily.

Spinning: spinning is used to make axis-symmetric parts by relative rotation of a piece of sheet stock and rollers or rigid tools. The rollers or rigid tools are pressed against the stock, stretching it, until the stock takes the required shape. The stock may be pressed against a mandrel but not necessarily.

Deep drawing: deep drawing is, as for stamping, a process of forming sheet metal through a forming die with a punch. In deep-drawing, the material undergoes high plastic deformations: deep drawing is often used to produce metal objects that are more than half their diameters in height; if the height is less than half their diameter we talk about drawing (which is also covered by this subclass). Often but not always, the blank is holded by a blank-holder to control the flow of material and to prevent the formation of wrinkles.

References relevant to classification in this group
This subclass/group does not cover:
Marking devices by stamping
Special deep-drawing arrangements in, or in connection with, presses

Places where the subject matter of this subclass group) is covered when specially adapted, used for a particular purpose, or incorporated into a larger system:

Pressing or stamping ornamental designs on surfaces of sheet metal
Processes for producing ornamental structures by stamping sheet metal
Informative references
Attention is drawn to the following places, which may be of interest for search:
Bending by stretching or pulling over a die
Shaping sheet metal over a die without external former
Shaping without cutting otherwise than using rigid devices or tools or yieldable or resilient pads
Special deep-drawing arrangements in, or in connection with, presses
Definition statement
This subclass/group covers:

General aspects of the deep-drawing apparatus as such.

Special deep-drawing arrangements in presses as for example feeding, centering of the blanks, guiding the tools.

Multi-stage deep-drawing presses.

The special devices for holding the metal sheet during deep-drawing (blank-holders and die cushions) as well as the devices for controlling or operating them during deep-drawing.

Blank holders: mechanisms which hold the borders of the blanks in order to control the flow of material during the drawing operation and to prevent wrinkles.

Cushioning arrangements: they are utilized for absorbing the force from the upper die so that the blank holder is moved downwardly, together with the punch, in a controlled manner.

Additional equipment in association with the deep-drawing tools e.g. for shearing, for trimming.

Informative references
Attention is drawn to the following places, which may be of interest for search:
Trimming deep-drawn products
Presses, drive of the presses in general, details of the presses (frame, table, ...)
Gas springs in general
Numerical control of the blank holders
Working sheet metal of limited length by stretching, e.g. for straightening
Definition statement
This subclass/group covers:

Methods and devices for working sheet metal of limited length by stretching, e.g. for straightening, by pulling over a die. It also covers the clamping arrangements needed to apply the stretching force to the sheet metal.

Shaping without cutting otherwise than using rigid devices or tools or yieldable or resilient pads, i.e. applying fluid pressure or magnetic forces (stamping using resilient pads B21D 22/10 )
Definition statement
This subclass/group covers:

Methods and devices for shaping sheet metal by the effect of non rigid means which are

fluids or

magnetic forces.

References relevant to classification in this group
This subclass/group does not cover:
Stamping using yieldable or resilient pads
by applying fluid pressure
Definition statement
This subclass/group covers:

Devices and methods for deforming sheet metal blanks in the form of sheets or thin plates, of tubes with or without bottom, or of profiles, by applying fluid pressure.

Informative references
Attention is drawn to the following places, which may be of interest for search:
Making other parts for vehicles, e.g. cowlings, mudguards
Treating or finishing surfaces by applying fluid pressure (Autofrettage)
Modifying the physical properties of steel by deformation (Autofrettage)
Special rules of classification within this group

Multi-aspect classification (i.e., allocating several subgroups to a document within the same subgroup) is applied to technical subjects under this subgroup with respect to the features of the deformation process or device according to subgroups B21D 26/021 - B21D 26/051 and with respect to the particular material features of the bodies to be deformed according to subgroups B21D 26/053 - B21D 26/059.

Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Fluid
Comprises gas, liquids, fluent particulate materials (e.g. sand) and materials which easily show plastic flow (e.g. soft metals such as lead)
Deforming sheet bodies
Definition statement
This subclass/group covers:

Devices and methods for deforming sheet metal in the form of flat sheets or thin plates, whether layered or not, by applying fluid pressure.

Special rules of classification within this group

When the invention is characterised by the shape of the bodies to be deformed in combination with a particular material feature of the bodies to be deformed, the invention shall also be classified in B21D 26/053 and subgroups thereof.

including an additional treatment performed by fluid pressure, e.g. perforating
Definition statement
This subclass/group covers:

Devices and methods for deforming sheet bodies by fluid pressure and performing a piercing, perforating, caulking, marking or other additional treatment by applying fluid pressure to the bodies being deformed.

Informative references
Attention is drawn to the following places, which may be of interest for search:
Shaping by press-cutting
Perforating by punching
Stabbing or piercing
Combined processes according to methods coverd by groups B21D 1/00-B21D 31/00
Application of shaping procedures without cutting in order to connect objects or parts, e.g. coating with sheet metal otherwise than plating
Uniting components by forging or pressing to form integral members
Press-fitting, force-fitting, or shrinking in general
B21P11/00
Means for controlling the clamping or opening of the moulds
Definition statement
This subclass/group covers:

Control means characterised by the control of clamping the mould and opening the mould, e.g. control of the pressure to be applied on the moulds when clamping or opening moulds.

Means for controlling fluid parameters, e.g. pressure or temperature
Definition statement
This subclass/group covers:

Control means for controlling supply pressure, temperature or other variables of the fluid at the time of supply. Means for merely controlling pumps are not included.

Informative references
Attention is drawn to the following places, which may be of interest for search:
Pumps or control of pumps per se
Closing or sealing means
Definition statement
This subclass/group covers:

Means and details that are relevant for the sealed or airtight closing of the mould.

Informative references
Attention is drawn to the following places, which may be of interest for search:
Sealings
Mould construction (B21D 26/025 - B21D 26/029 take precedence)
Definition statement
This subclass/group covers:

Constructional features or details of the mould, e.g. a mould of which some portion is movable, which are not covered by other subgroups of B21D 26/021.

References relevant to classification in this group
This subclass/group does not cover:
Means for controlling the clamping or opening of the moulds
Means for controlling fluid parameters, e.g. pressure or temperature
Closing or sealing means
Deforming tubular bodies (corrugating tubes by applying fluid pressure B21D 15/03, B21D 15/10)
Definition statement
This subclass/group covers:

Devices and methods for deforming sheet metal in the form of metal tubes, e.g. cylinders, with or without bottom, by applying fluid pressure.

References relevant to classification in this group
This subclass/group does not cover:
Corrugating tubes by applying fluid pressure
Informative references
Attention is drawn to the following places, which may be of interest for search:
Tube expanders
Special rules of classification within this group

When the invention is characterised by the shape of the bodies to be deformed in combination with a particular material feature of the bodies to be deformed, the invention shall also be additionally classified in B21D 26/053 and subgroups thereof.

including an additional treatment performed by fluid pressure, e.g. perforating
Definition statement
This subclass/group covers:

Devices and methods for deforming tubular bodies by fluid pressure and performing a piercing, perforating, caulking, marking or other additional treatment by applying fluid pressure on the bodies being deformed.

Informative references
Attention is drawn to the following places, which may be of interest for search:
Shaping by press-cutting
Perforating by punching
Stabbing or piercing
Combined processes according to methods coverd by groups B21D 1/00-B21D 31/00
Application of shaping procedures without cutting in order to connect objects or parts, e.g. coating with sheet metal otherwise than plating
Uniting components by forging or pressing to form integral members
Press-fitting, force-fitting, or shrinking in general
B21P11/00
Forming branched tubes
Definition statement
This subclass/group covers:

Devices and methods for deforming metal tubular bodies by applying fluid pressure specially adapted to obtain branched tubes

Informative references
Attention is drawn to the following places, which may be of interest for search:
Making branched tube fittings, e.g. T-pieces for connecting pipes
Means for controlling the clamping or opening of the moulds
Definition statement
This subclass/group covers:

Control means characterised by the control of clamping the mould and opening the mould, e.g. control of the pressure to be applied on the moulds when clamping or opening moulds.

Means for controlling fluid parameters, e.g. pressure or temperature
Informative references
Attention is drawn to the following places, which may be of interest for search:
Pumps or control of pumps per se
Special rules of classification within this group

Control means for controlling supply pressure, temperature or other variables of the fluid at the time of supply. Means for merely controlling pumps are not included.

Means for controlling the axial pusher
Definition statement
This subclass/group covers:

Control means characterised by the control of the axial movement (speed, timing, steps) of, the counter-pressure applied to, or other variables of the axial pusher during the deformation process.

Closing or sealing means
Definition statement
This subclass/group covers:

Details of the sealed or airtight closing of the mould.

Informative references
Attention is drawn to the following places, which may be of interest for search:
Sealings
Mould construction (B21D 26/037 - B21D 26/045 take precedence)
Definition statement
This subclass/group covers:

Constructional features or details of the mould, e.g. a mould of which some portion is movable, which are not covered by other subgroups of B21D 26/033.

References relevant to classification in this group
This subclass/group does not cover:
Forming branched tubes
Means for controlling the clamping or opening of the moulds
Means for controlling fluid parameters, e.g. pressure or temperature
Means for controlling the axial pusher
Closing or sealing means of the mould
Deforming bodies having a closed end
Definition statement
This subclass/group covers:

Devices and methods for deforming metal tubular bodies having a bottom, i.e. a closed end, by applying fluid pressure.

Special rules of classification within this group

When an invention is characterised by the shape of the bodies to be deformed in combination with a particular material feature of the bodies to be deformed, the invention shall additionally be classified in B21D 26/053 and subgroups thereof.

Deforming double-walled bodies
Definition statement
This subclass/group covers:

Devices and methods for deforming metal double-walled tubular bodies by applying fluid pressure.

Special rules of classification within this group

When an invention is characterised by the shape of the bodies to be deformed in combination with a particular material feature of the bodies to be deformed, the invention shall be classified in B21D 26/053 and subgroups thereof.

characterised by the material of the blanks
Definition statement
This subclass/group covers:

Devices and methods for deforming metal bodies by applying fluid pressure which are characterised by the material, composition or constituents of the bodies to be deformed.

Special rules of classification within this group

When an invention is characterised by the adaptation to deforming metal bodies with a particular material feature in combination with the shape of the bodies to be deformed, the invention shall also be classified in B21D 26/021 or B21D 26/033 and their subgroups.

Blanks having super-plastic properties
Definition statement
This subclass/group covers:

Devices and methods adapted for deforming metal bodies comprising a material having super-plastic properties, e.g. a super-plastic alloy, by applying fluid pressure.

Tailored blanks
Definition statement
This subclass/group covers:

Devices and methods adapted for deforming metal bodies preassembled from different pieces, e.g. pieces of different materials or pieces of different thickness, by applying fluid pressure.

Layered blanks
Definition statement
This subclass/group covers:

Devices and methods adapted for deforming layered blanks by applying fluid pressure.

Informative references
Attention is drawn to the following places, which may be of interest for search:
Layered products essentially comprising metal
Glossary of terms
In this subclass/group, the following terms (or expressions) are used with the meaning indicated:
Layered blank
Blank consisting of several layers of material comprising at least one metal layer, e.g. a blank from a sheet metal coated with resins or a laminate of sheet metals with different degrees of hardness.
Shaping by press-cutting; Perforating
Definition statement
This subclass/group covers:

Methods and devices for shaping sheet metal by press-cutting comprising:

Specific aspects of the drive of press-cutting tools.

Explosive cutting.

Centering the work, positioning the tools.

Making more than one part out of the same blank or strip.

Incompletely punching in such a manner that the parts are still coherent with the work.

Punching using rotatable carriers (e.g., turret punch presses).

Blanking dies.

Shoulder or burr prevention, which particularly covers fine-blanking.

Yieldable punching pads.

Applications of drive in order to reduce noise and/or wear.

Notching the peripheries or circular blanks.

Methods and devices for perforating, i.e. punching holes in metal profiles, sheets or flat parts, tubes or hollow bodies, annular parts, other articles of special shape (means that the shape is so that cam systems are necessary to access the perforating location).

Specific aspects of the drive of perforating tools and explosive perforating.

Perforating tools and die holders.

References relevant to classification in this group
This subclass/group does not cover:
Ejecting or stripping-off devices arranged in punching machines or tools
Cutting nails or pins from strips or sheet material
Shearing or nibbling metal sheets, tubes or profiles
Other methods for working sheet metal, metal tubes, metal profiles (deforming one surface of tubes helically by rolling B21H 3/00 ; upsetting B21J 5/08 ; working metal by removing material therefrom B23 ; embossing B44B )
Definition statement
This subclass/group covers:

Methods and devices other than straightening, bending, corrugating, stamping, spinning, deep-drawing, stretching, punching.

For example:

shaping with a tool pressed against a sheet stock and without die or counter tool (e.g.: single point forming);

stabbing or piercing, e.g. for making sieves;

expanding after slitting for making expanded metal, gratings;

deforming by sequential impacts like hammering, beating.

Informative references
Attention is drawn to the following places, which may be of interest for search:
Expanding tube ends
Deforming one surface of tubes helically by rolling
Upsetting
Special measures in connection with working metal foils, e.g. gold foils (cutting or perforating of metal foil analogous to paper B26 )
Definition statement
This subclass/group covers:

Special measures to adapt sheet metal working apparatus according to subclass B21D for working metal foils, e.g. gold foils

Informative references
Attention is drawn to the following places, which may be of interest for search:
Manufacturing of metal foils from a thick stock
Perforating, cutting or severing of metal foils in a manner analogous to the working of paper
B26
Bending, corrugating, stamping metal foils in a manner analogous to the working of paper
B31
Combined processes according to methods covered by groups B21D 1/00 to B21D 31/00 ( B21D 21/00 takes precedence)
Definition statement
This subclass/group covers:

Processes combining two or more metal working methods covered by the above groups and listed below:

straightening,

bending,

corrugating,

forming single grooves,

flanging or other edge treatment,

stamping,

spinning,

deep-drawing,

stretching,

shaping by applying fluid pressure or by applying magnetic forces,

punching blanks, perforating,

other methods for working sheet metal (single point forming, stabbing or piercing, expanding, hammering,...),

special measures in connection with working metal foils.

Tools as parts of machines covered by this subclass (forms or constructions of tools uniquely adapted for particular operations in the relevant groups for the operations)
Definition statement
This subclass/group covers:

Tools as parts of machines covered by this subclass (forms or constructions of tools uniquely adapted for particular operations in the relevant groups for the operations).

Selection of materials for the tools.

Die constructions enabling assembly of the die parts in different ways: the shape of the tool can be changed by moving or exchanging certain parts of the tool.

Movable or exchangeable mountings for tools: all systems to hold, clamp, lock the tools in their working place.

Dies with different parts for several steps in a process: e.g., progressive stamping dies, succession of tools for shaping in several steps, succession of a blanking station and drawing stations.

Dies sets: complementary dies which cooperate by the means of guiding means; the die sets are adapted to be mounted between the ram and the table/bolster of a press.

Pillar guides: details of guiding arrangements of die sets.

Particular arrangements for handling and holding in place complete dies in order to install them for example in a press.

Heating or cooling the tools.

Lubricating of the tools or tools including lubricating of the workpiece.

Making tools by operations not covered by a single other subclass, by using techniques of the present subclass: e.g. cutting tools obtained by bending a metal strip.

References relevant to classification in this group
This subclass/group does not cover:
Yieldable or resilient stamping tools
Additional equipments in association with the tools for deep-drawing
Mounting of simple tools like perforating punches
Informative references
Attention is drawn to the following places, which may be of interest for search:
Mounting of dies, platens or press rams
Loading or unloading of dies
Guides for presses
Press plates with heating or cooling means
Heating or cooling presses and parts thereof
Coating metal sheets (with oil or others)
Lubricating or coating of blanks for deep-drawing
Lubricating in general
Application of procedures in order to connect objects or parts, e.g. coating with sheet metal otherwise than by plating ( [N: joining mitred profiles B21D 53/745 ;] riveting B21J ; uniting components by forging or pressing to form integral members B21K 25/00 ; welding B23K ; press-fitting, force-fitting, or shrinking in general B23P 11/00 , B21D 19/00 ; by adhesives F16B 11/00 ) ; Tube expanders
Definition statement
This subclass/group covers:

Methods and devices for connecting objects or parts by sheet metal deformation:

coating objects or parts with sheet metal,

connecting sheet metal with sheet metal,

connecting metal tubes with metal tubes (also tube-like fittings),

connecting tubes with rods,

connecting of tubes in openings,

as well as tube expanding devices as such.

References relevant to classification in this group
This subclass/group does not cover:
Riveting
Uniting components by forging or pressing to form integral members
Welding
Force-fitting, or shrinking in general
Connecting by adhesives

Places where the subject matter of this subclass group) is covered when specially adapted, used for a particular purpose, or incorporated into a larger system:

Connecting metal panels in roof working
Setting of casings, screens, liners in wells
Expanding tools specially adapted for wellbores
Crimping electrical connections
Joining mitred profiles
Informative references
Attention is drawn to the following places, which may be of interest for search:
Flanging
Joining sub-units of motor vehicles or trailers
Connections as such in roof coverings obtained by forcing together the marginal portions of adjacent slabs or sheet
Connections as such in general (products)
Application of procedures in order to alter the diameter of tube ends ( B21D 39/00 takes precedence)
Definition statement
This subclass/group covers:

Methods and devices for enlarging, reducing or closing tube ends.

Feeding, positioning or storing devices combined with, or arranged in, or specially adapted for use in connection with, apparatus for working or processing sheet metal, metal tubes or metal profiles; Associations therewith of cutting devices (cutting devices associated with the tool, see the relevant group for the tool)
Definition statement
This subclass/group covers:
Methods and devices for feeding, positioning or storing combined with, or arranged in, or specially adapted for use in connection with the apparatus for mechanical working of sheet metal or metal tubes, rods or profiles without essentially removing material or with the apparatus for press-cutting, sheet metal or other metal stock material. Associations of cutting devices with the above feeding, positioning or storing devices.
References relevant to classification in this subclass/group
This subclass/group does not cover:
Cutting devices not associated with the feeding, positioning or storing device but with the tool itself
See the relevant group, e.g. B21D 24/16
Informative references
Attention is drawn to the following places, which may be of interest for search:
Feeding wire or rods
Feeding, positioning in machine tools and in metal-working not otherwise provided for
Manipulators
Transport or storage in general
Handling thin or filamentary material
Ejecting or stripping-off devices arranged in machines or tools dealt with in this subclass
Definition statement
This subclass/group covers:

Ejecting or stripping-off devices arranged in machines or tools dealt with in this subclass and corresponding methods.

Ejecting covers ejecting the worked part or the scrap out of the tool or transporting them out of the working device.

Stripping-off covers separating the worpiece from a perforating punch after punching or from a punching die after forming.

Making statical construction, e.g. honeycomb structures
Definition statement
This subclass/group covers:

Processing sheet metal or metal tubes, or processing metal profiles according to any of groups B21D 1/00- B21D 45/00, in the manufacture of finished or semi-finished articles for making statical constructions as for example honeycomb structures, beams or pillars.

Sheathing or stiffening objects (by winding wire or tape thereon B65H 54/00 , B65H 81/00 ; specially adapted for manufacturing conductors or cables H01B 13/26 )
Definition statement
This subclass/group covers:

Processing sheet metal or metal tubes, or processing metal profiles according to any of groups B21D 1/00- B21D 45/00 for sheathing or stiffening objects.

Informative references
Attention is drawn to the following places, which may be of interest for search:
Sheathing or stiffening objects by winding wire or tape thereon
Sheathing or stiffening objects specially adapted for manufacturing conductors or cables
Making hollow objects (from thick-walled or non uniform tubes B21K 21/00 )
Definition statement
This subclass/group covers:

Processing sheet metal or metal tubes, or processing metal profiles according to any of groups B21D 1/00- B21D 45/00, in the manufacture of hollow objects, e.g. hollow objects not characterized by the particular use or hollow objects characterized by the particular use (e.g, vessels, high pressure containers, cans or tins, collapsible or like thin-walled tubes, inlet or outlet arrangements, can ends or closures there for, boxes, cigarette cases or the like, cartridge cases).

References relevant to classification in this group
This subclass/group does not cover:
Re-forming tubes from doubled flat material
Making hollow objects from thick-walled or non-uniform tubes
Making closures, e.g. caps folded of thin metal foils in the way of making paper caps
Informative references
Attention is drawn to the following places, which may be of interest for search:
Containers
Closing containers or receptacles after filling
Making closures in conjunction with applying same
Making heat exchangers
Making other particular articles (making chains or chain parts B21L )
Definition statement
This subclass/group covers:

Processing sheet metal or metal tubes, or processing metal profiles according to any of groups B21D 1/00- B21D 45/00, for making other particular articles. The processes covered by this group are special processes for producing a specific article (e.g. heat exchangers, wheels, parts for vehicles, etc...). Processes in general are covered by the relevant group of this subclass.

References relevant to classification in this group
This subclass/group does not cover:

Places where the subject matter of this subclass group) is covered when specially adapted, used for a particular purpose, or incorporated into a larger system:

Making chains or chain parts
Safety devices protecting the machine or the operator, specially adapted for apparatus or machines dealt with in this subclass (for presses in general B30B ; safety devices in general F16P ) )
Definition statement
This subclass/group covers:

Safety devices and methods for protecting the machine or the operator, specially adapted for apparatus or machines dealt with in this subclass. Noise reducing measures are also covered.

Informative references
Attention is drawn to the following places, which may be of interest for search:
Safety devices for presses
Safety devices in general
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Last Modified: 10/11/2013