|  | B |
SECTION B — PERFORMING OPERATIONS; TRANSPORTING

SHAPING

|  | B21 |
MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL (casting, powder metallurgy Fulltext... Hierarchy... Expanded...B22; shearing Fulltext... Hierarchy... Expanded...B23D; working of metal by the action of a high concentration of electric current Fulltext... Hierarchy... Expanded...B23H; soldering, welding, flame-cutting Fulltext... Hierarchy... Expanded...B23K; other working of metal Fulltext... Hierarchy... Expanded...B23P; punching sheet material in general Fulltext... Hierarchy... Expanded...B26F; processes for changing of physical properties of metals Fulltext... Hierarchy... Expanded...C21D, Fulltext... Hierarchy... Expanded...C22F; electroforming Fulltext... Hierarchy... Expanded...C25D 1/00)

|  | B21 |
Note(s) This class does not cover: combinations of operations covered by different subclasses of class Fulltext... Hierarchy... Expanded...B21, which are covered by subclass Fulltext... Hierarchy... Expanded...B23P; combinations of operations covered by any particular subclass of class Fulltext... Hierarchy... Expanded...B21 with operations covered by other classes, e.g. with operations involving removal of material, which are also covered by subclass Fulltext... Hierarchy... Expanded...B23P, except that if the operations covered by the other classes are subsidiary to the operations properly covered by a single subclass of Fulltext... Hierarchy... Expanded...B21 the combination is classified in that subclass. Processes of a kind covered by this class but applied to non-metallic materials are classified in this class if they are applicable to metal and cannot be classified fully in another class.

|  | B21L |
MAKING CHAINS (chains in general Fulltext... Hierarchy... Expanded...F16G)

|  | B21L |
Subclass index
GENERAL METHODS OF WORKING |
Chains made from individual links | 1/00, 3/00, 7/00, 9/00
Chains with integral links | 5/00
METHODS FOR MAKING SPECIAL CHAINS OR PARTS THEREOF | 11/00, 13/00
TOOLS FOR MANUFACTURE OR REPAIR | 19/00, 21/00
FINISHING | 15/00
OTHER MANUFACTURE | 17/00

|  | B21L 1/00 |
Making chains or chain links by bending workpieces of rod, wire, or strip to form links of oval or other simple shape (Fulltext... Hierarchy... Expanded...B21L 3/00, Fulltext... Hierarchy... Expanded...B21L 7/00 take precedence)

|  | B21L 1/02 |
· | by bending the ends of the workpieces to abut

|  | B21L 1/04 |
· | by bending and interconnecting the ends of the workpieces with or without separate jointing members

|  | B21L 3/00 |
Making chains or chain links by bending the chain links or link parts and subsequently welding or soldering the abutting ends (Fulltext... Hierarchy... Expanded...B21L 7/00 takes precedence)

|  | B21L 3/02 |
· | Machines or devices for welding chain links

|  | B21L 3/04 |
· · | by making use of forge or pressure welding

|  | B21L 5/00 |
Making chains or chain links by working the starting material in such a way that integral, i.e. jointless, chain links are formed

|  | B21L 5/02 |
· | in such a way that interconnected links are formed

|  | B21L 7/00 |
Making chains or chain links by cutting single loops or loop-parts from coils, assembling the cut parts and subsequently subjecting same to twisting with or without welding

|  | B21L 9/00 |
Making chains or chain links, the links being composed of two or more different parts, e.g. drive chains (Fulltext... Hierarchy... Expanded...B21L 1/04, Fulltext... Hierarchy... Expanded...B21L 7/00, Fulltext... Hierarchy... Expanded...B21L 11/14, Fulltext... Hierarchy... Expanded...B21L 13/00 take precedence)

|  | B21L 9/02 |
· | of roller-chain or other plate-link type

|  | B21L 9/04 |
· · | Punching or bending the different parts of the chain links

|  | B21L 9/06 |
· · | Sorting, feeding, assembling, riveting, or finishing parts of chains

|  | B21L 9/08 |
· · | Combining the chain links with auxiliary parts, e.g. welding-on wear-resistant parts

|  | B21L 11/00 |
Making chains or chain links of special shape

|  | B21L 11/02 |
· | each link being formed of a single member of which both ends are bent or shaped to engage the middle portion of the next link

|  | B21L 11/04 |
· · | the ends being pierced or punched to form eyes

|  | B21L 11/06 |
· · · | the workpiece being of thin strip metal

|  | B21L 11/08 |
· · | the ends being interengaged with other parts of the same link

|  | B21L 11/10 |
· | the chain links having opposed correspondingly shaped cylindrical and hook-like parts of which one part forms a hinge-like support for the adjacent link (Fulltext... Hierarchy... Expanded...B21L 11/02 takes precedence)

|  | B21L 11/12 |
· | Forming bead chains

|  | B21L 11/14 |
· | Making chain links with inserted or integrally- formed studs

|  | B21L 13/00 |
Making terminal or intermediate chain links of special shape; Making couplings for chains, e.g. swivels, shackles

|  | B21L 15/00 |
Finishing or dressing chains or chain links, e.g. removing burr material, calibrating (Fulltext... Hierarchy... Expanded...B21L 9/06 takes precedence)

|  | B21L 15/02 |
· | Twisting already closed links

|  | B21L 17/00 |
Making chains or chain links not covered by one of the preceding main groups (by casting Fulltext... Hierarchy... Expanded...B22D 25/02)

|  | B21L 19/00 |
Appurtenances for chain-making not restricted to any particular process

|  | B21L 21/00 |
Tools or implements for repairing chains using metal-working operations, e.g. for detaching deformed chain links