WCO Explanatory Notes reproduced for reference. © World Customs Organization. Verify against official WCO publication.
84.83 Transmission shafts (including cam shafts and crank shafts) and cranks; bearing housings and plain shaft beamgs; gears and gearing; ball or roller screws; gear boxes and other speed changers, ~ncludingtorque converters; flywheels and pulleys, including pulley blocks; clutches and shaft couplings (including universal joints). Transmission shafts (including cam shafts and crank shafts) and cranks 8483.10 - 8483.20 8483.30 - Bearing housings, incorporating ball or roller bearings - Bearing housings, not incorporating ball or roller bearings; plain shaft 8483.40 - Gears and gearing, other than toothed wheels, chain sprockets and other bearings transmission elements presented separately; ball or roller screws; gear boxes and other speed changers, including torque converters 8483.50 - Flywheels and pulleys, including pulley blocks 8483.60 8483.90 - Clutches and shaft couplings (including universal joints) - Toothed wheels, chain sprockets and other transmission elements presented separately; parts. The goods covered by this heading are mainly : (i) Certain mechanical parts which are used in the transmission of power from an external power unit to one or more machines. (ii) Certain internal parts of a machine, used to transmit power to the various parts of the same machine. (A) TRANSMISSION SHAFTS (INCLUDING CAM SHAFTS AND CRANK SHAFTS) AND CRANKS These usually transmit a rotary motive power. They include : (1) Main shafts or driving shafts driven directly by the motor. (2) Counter shafts, for coupling to the main shaft by belts and pulleys or by cogs, etc.; they are used to take the drive from the main shaft to a number of machnes, or to dfferent parts of a machine. (3) Articulated shafts, consisting of two or more shafis connected by ball and socket joints, etc. (4) Flexible shafts which transmit the motion of a driving unit to, e-g., hand tools, measuring instruments (revolution counters, speedometers, etc.). (5) Cranks and crank shafts. These may be either made in one piece or assembled fxom several parts. They receive a reciprocating motion (e-g., from a piston engine) and convert it into rotary movement, or vice versa. (6) Cam shafts and eccentric shafts. The heading does not cover simple axles which do not transmit power but merely support a wheel or other revolving part. It also excludes : (a) Bars of iron or steel of uniform cross-section (heading 72.14 or 72.15). (b) Simple lengths of twisted wire for the manufacture of flexible drives, not fitted with coupling attachments (heading 73.12). (c) Oscillatin connecting-rods for transmitting motion to cutter bars of lawn mowers or grass cutters (heading i4.33). (B) BEARING HOUSINGS AND PLAIN SHAFT BEARINGS Bearing housings consist of a f'rame or block designed to house the plain, ball, roller, etc., bearing in which (or, in the case of a thrust bearin , against which) the ends of a shafi or axle turn. They usually consist of two parts which, w en fitted together, form a ring to hold the bearing. They may incorporate means of lubricating the bearing. t The also often inco orate a chair, plate, bracket, etc., by which they can be fixed to the mac ine, or to a wa 1 or other part of a building; but chairs, plates, brackets, etc., not incorporating a bearing housing (nor themselves designed to house a bearing) are classified according to the constituent material (usually heading 73.25 or 73.26). Z T Bearing housin s incorporatin ball, roller or needle roller bearings remain classified in this heading; but ba ,roller or nee e roller bearings presented separately fall in heading 84.82. di ti On the other hand plain shaft bearings are classified in this headin even if the are presented without housings. They consist of rings of anti-friction metal or o er rnateriy(e.g., sintered metal or plastics). They ma be in one piece or in several pieces clamped together, and form a smooth bearing in which a s aft or axle turns. The heading does not include graphite or other carbon bearings (heading 68.15). (C) GEARS AND GEARING INCLUDING FRICTION GEARS AND CHAIN SPROCKETS The basic gear is the toothed wheel, cylinder, cone, rack or worm, etc. In an assembly of such gears, the teeth of one engage with the teeth of another so that the rotary movement of the first is transmitted to the next, and so on. Accordin to the relative number of teeth in the separate units, the rotary movement may be transmitte at the same rate, or at a faster or slower rate; according to the e of gear and the angle at which it meshes with the next, the direction of transmission may e changed, or a rotary movement converted into a linear movement or vice versa (as with a rack and pmion). % 9' The group covers all types of ears including simple cog wheels, bevel gears, conical ears, helical gears, worms, rack an pinion gears, differential gears, etc., and assemblies o such gears. It also covers toothed and similar wheels for use with transmission chains. d B The group also covers friction gears. These are wheels, discs or cylinders, which, when mounted one on the driving shaft and one on the driven shaft, transmit the movement by friction between them. The are usually of cast iron, in certain cases being covered with leather, wood, bonded fibres or ot er material to increase the friction. E (D) BALL OR ROLLER SCREWS Ball or roller screws consist of a threaded shaft and a nut with bearing balls or rollers distributed along the path between the threads on its inner surface; these devices enable rotary motion to be converted into linear motion, and vice versa. (E) GEAR BOXES AND OTHER SPEED CHANGERS, INCLUDING TORQUE CONVERTERS These provide a range of speeds which can be varied, either by hand or automatically, according to the requirements of the machine. They include, inter alia : (1) Gear-boxes consisting of assemblies of ears which can be selected in alternative arrangements; the speed of transmission can fi,us be varied according to the arrangement of gears set. (2) Friction disc or friction cone cou lings and couplings with chains or driving belts, in which a disc, a cone, a chain or a elt is in contact mth a friction wheel whose osition, relative to the centre of the disc or the ends of the cone, can be varied autornatica y (or as required), and so controls the speed of rotation transmitted. R R (3) Variable speed fluid cou lings, including hydraulic torque converters. Variations are obtained by the rotation o vanes of the driving element in a fluid (generally oil) against fixed or movable vanes of the driven element. Power is.transmitted either by pressure (hydrostatic changers) or by flux (hydrodynamic changers or torque converters). P The heading does not cover ear boxes or other variable speed changers combined with a motor; these are classified in the same hea mng as the motor. d: (F) FLYWHEELS These are relatively large, heavy wheels, usually constructed so that the weight is concentrated near the rim. The inertia of the wheel as it turns tends to resist any change in speed of the motor and so keeps the speed constant. Fl heels may in some cases have a grooved or cogged rim, or be fitted w t h connecting-rods, so t at in certain circumstances they can act for the transmission of power (e.g., as a driving pulley or cog wheel). K" (G) PULLEYS, INCLUDING PULLEY BLOCKS Pulleys consist of wheels, sometimes with a grooved rim, which transmit r o t . movement from one to another by means of an endless belt or ro e revolving in contact between them. The conical pulleys, stepped pulleys, etc. heading covers simple pulleys, drums (wide The group also covers ower themselves but e.g., idlers and jockey P blocks for hoists, etc., and free pulleys which do not transmit any act as a guide or turning post for a transmission rope or cable used to regulate the tension of driving belts). An assembly of two or more pulley blocks (i.e.,a hoist) is, however, excluded (heading 84.25). 0CLUTCHES These are used to connect or disconnect the drive at will. They include : Friction clutches in which rotating discs, rings, cones, etc. with friction surfaces, can be engaged or disenga ed; dog (or claw) clutches in which the op osing members have projections and correspon mg slots; automatic centrifugal clutches whic engage or disengage according to the speed of rotation; compressed air clutches; hydraulic clutches; etc. d R Electro-magnetic clutches, however, are excluded (heading 85.05). (IJ) SHAFT COUPLINGS (INCLUDING UNIVERSAL JOINTS) These include sleeve couplings, flan e couplings, flexible couplings, hydraulic couplings, etc., and universal couplings (such as Car an joints and Oldham couplings). % PARTS Sub'ect to the general provisions re arding the classification of parts (see the General Exp anatory Note to Section XVI), the eading also covers parts of the goods covered by this heading. f The heading also excludes : (a) Pieces roughly shaped by forging, of heading 72.07. I (b) Transmission equipment of the kinds described above gear boxes? tsansmjssion shafts, clu.tches, hfferentials, etc.), but which are designed for use sole y or pmcipally wth vehicles or amraft (Section XVII); it should, however, be noted that this exclusion does not apply to internal parts of vehicle or aircraft engines - these parts remain classified in this heading. Thus a: crank shaft or a cam shaR remains in this heading even if it is specialised for a motor car engine; but motor car transmission (propeller) shafts, gear boxes and differentials fall in heading 87.08. It should further be noted that transmission e uiplnent of the type described in this heading remains classified here even if it IS specially des~gnedo!r slups. (c) Parts of clocks or watches (heading 91.14).
Notes. 1.- This Chapter does not cover : (a) Millstones, grindstones or other articles of Chapter 68; (b) Machinery or appliances (for example, pumps) of ceramic material and ceramic parts of machinery or appliances of any material (Chapter 69); (c) Laboratory glassware (heading 70.17); machinery, appliances or other articles for technical uses or parts thereof, of glass (heading 70.19 or 70.20); (d) Articles of heading 73.21 or 73.22 or similar articles of other base metals (Chapters 74 to 76 or 78 to 81); (e) Vacuum cleaners of heading 85.08; (f) Electro-mechanical domestic appliances of heading 85.09; digital cameras of heading 85.25; (g) Radiators for the articles of Section XVII; or (h) Hand-operated mechanical floor sweepers, not motorised (heading 96.03). 2.- Subject to the operation of Note 3 to Section XVI and subject to Note 11 to this Chapter, a machine or appliance which answers to a description in one or more of the headings 84.01 to 84.24, or heading 84.86 and at the same time to a description in one or more of the headings 84.25 to 84.80 is to be classified under the appropriate heading of the former group or under heading 84.86, as the case may be, and not the latter group. (A) Heading 84.19 does not, however, cover : (i) Germination plant, incubators or brooders (heading 84.36); (ii) Grain dampening machines (heading 84.37); (iii) Diffusing apparatus for sugar juice extraction (heading 84.38); (iv) Machinery for the heat-treatment of textile yarns, fabrics or made up textile articles (heading 84.51); or (v) Machinery, plant or laboratory equipment designed for a mechanical operation, in which a change of temperature, even if necessary, is subsidiary. (B) Heading 84.22 does not cover : (i) Sewing machines for closing bags or similar containers (heading 84.52); or (ii) Office machinery of heading 84.72. (C) Heading 84.24 does not cover : (i) Ink-jet printing machines (heading 84.43); or (ii) Water-jet cutting machines (heading 84.56). 3.- A machine-tool for working any material which answers to a description in heading 84.56 and at the same time to a description in heading 84.57, 84.58, 84.59, 84.60, 84.61, 84.64 or 84.65 is to be classified in heading 84.56. 4.- Heading 84.57 applies only to machine-tools for working metal, other than lathes (including turning centres), which can carry out different types of machining operations either : (a) by automatic tool change from a magazine or the like in conformity with a machining programme (machining centres), (b) by the automatic use, simultaneously or sequentially, of different unit heads working on a fixed position workpiece (unit construction machines, single station), or (c) by the automatic transfer of the workpiece to different unit heads (multi-station transfer machines). 5.- For the purposes of heading 84.62, a “slitting line” for flat products is a processing line composed of an uncoiler, a coil flattener, a slitter and a recoiler. A “cut-to-length line” for flat products is a processing line composed of an uncoiler, a coil flattener, and a shear. 6.- (A) For the purposes of heading 84.71, the expression “automatic data processing machines” means machines capable of : (i) Storing the processing program or programs and at least the data immediately necessary for the execution of the program; (ii) Being freely programmed in accordance with the requirements of the user; (iii) Performing arithmetical computations specified by the user; and (iv) Executing, without human intervention, a processing program which requires them to modify their execution, by logical decision during the processing run. (B) Automatic data processing machines may be in the form of systems consisting of a variable number of separate units. (C) Subject to paragraphs (D) and (E) below, a unit is to be regarded as being part of an automatic data processing system if it meets all of the following conditions : (i) It is of a kind solely or principally used in an automatic data processing system; (ii) It is connectable to the central processing unit either directly or through one or more other units; and (iii) It is able to accept or deliver data in a form (codes or signals) which can be used by the system. Separately presented units of an automatic data processing machine are to be classified in heading 84.71. However, keyboards, X-Y co-ordinate input devices and disk storage units which satisfy the conditions of paragraphs (C) (ii) and (C) (iii) above, are in all cases to be classified as units of heading 84.71. (D) Heading 84.71 does not cover the following when presented separately, even if they meet all of the conditions set forth in Note 6 (C) above : (i) Printers, copying machines, facsimile machines, whether or not combined; (ii) Apparatus for the transmission or reception of voice, images or other data, including apparatus for communication in a wired or wireless network (such as a local or wide area network); (iii) Loudspeakers and microphones; (iv) Television cameras, digital cameras and video camera recorders; (v) Monitors and projectors, not incorporating television reception apparatus. (E) Machines incorporating or working in conjunction with an automatic data processing machine and performing a specific function other than data processing are to be classified in the headings appropriate to their respective functions or, failing that, in residual headings. 7.- Heading 84.82 applies, inter alia, to polished steel balls, the maximum and minimum diameters of which do not differ from the nominal diameter by more than 1 % or by more than 0.05 mm, whichever is less. Other steel balls are to be classified in heading 73.26. 8.- A machine which is used for more than one purpose is, for the purposes of classification, to be treated as if its principal purpose were its sole purpose. Subject to Note 2 to this Chapter and Note 3 to Section XVI, a machine the principal purpose of which is not described in any heading or for which no one purpose is the principal purpose is, unless the context otherwise requires, to be classified in heading 84.79. Heading 84.79 also covers machines for making rope or cable (for example, stranding, twisting or cabling machines) from metal wire, textile yarn or any other material or from a combination of such materials. 9.- For the purposes of heading 84.70, the term “pocket-size” applies only to machines the dimensions of which do not exceed 170 mm x 100 mm x 45 mm. 10.- For the purposes of heading 84.85, the expression “additive manufacturing” (also referred to as 3D printing) means the formation of physical objects, based on a digital model, by the successive addition and layering, and consolidation and solidification, of material (for example, metal, plastics or ceramics). Subject to Note 1 to Section XVI and Note 1 to Chapter 84, machines answering to the description in heading 84.85 are to be classified in that heading and in no other heading of the Nomenclature. 11.- (A) Notes 12 (a) and 12 (b) to Chapter 85 also apply with respect to the expressions “semiconductor devices” and “electronic integrated circuits”, respectively, as used in this Note and in heading 84.86. However, for the purposes of this Note and of heading 84.86, the expression “semiconductor devices” also covers photosensitive semiconductor devices and light-emitting diodes (LED). (B) For the purposes of this Note and of heading 84.86, the expression “manufacture of flat panel displays” covers the fabrication of substrates into a flat panel. It does not cover the manufacture of glass or the assembly of printed circuit boards or other electronic components onto the flat panel. The expression “flat panel display” does not cover cathode-ray tube technology. (C) Heading 84.86 also includes machines and apparatus solely or principally of a kind used for : (i) the manufacture or repair of masks and reticles; (ii) assembling semiconductor devices or electronic integrated circuits; (iii) lifting, handling, loading or unloading of boules, wafers, semiconductor devices, electronic integrated circuits and flat panel displays. (D) Subject to Note 1 to Section XVI and Note 1 to Chapter 84, machines and apparatus answering to the description in heading 84.86 are to be classified in that heading and in no other heading of the Nomenclature. Subheading Notes. 1.- For the purposes of subheading 8465.20, the term “machining centres” applies only to machine-tools for working wood, cork, bone, hard rubber, hard plastics or similar hard materials, which can carry out different types of machining operations by automatic tool change from a magazine or the like in conformity with a machining programme. 2.- For the purposes of subheading 8471.49, the term “systems” means automatic data processing machines whose units satisfy the conditions laid down in Note 6 (C) to Chapter 84 and which comprise at least a central processing unit, one input unit (for example, a keyboard or a scanner), and one output unit (for example, a visual display unit or a printer). 3.- For the purposes of subheading 8481.20, the expression “valves for oleohydraulic or pneumatic transmissions” means valves which are used specifically in the transmission of “fluid power” in a hydraulic or pneumatic system, where the energy source is supplied in the form of pressurised fluids (liquid or gas). These valves may be of any type (for example, pressure-reducing type, check type). Subheading 8481.20 takes precedence over all other subheadings of heading 84.81. 4.- Subheading 8482.40 applies only to bearings with cylindrical rollers of a uniform diameter not exceeding 5 mm and having a length which is at least three times the diameter. The ends of the rollers may be rounded.