Machines for making optical fibres and preforms thereof

84.75 Machines for assembling electric or electronic lamps, tubes or valves or flash-bulbs, in glass envelopes; machines for manufacturing or hot working glass or glassware. 8475.10 - Machines for assemblin electric or electronic lamps, tubes or valves or f flash-bulbs, in glass enve opes - Machines for manufacturing or hot working glass or glassware : 8475.21 - - Machines for making optical fibres and preforms thereof 8475.29 - - Other 8475.90 - Parts The heading covers machines for assembling electric or electronic lamps, tubes or valves or flash-bulbs, in glass envelopes. It also includes machines for manufacturing or hot working glass or glassware (other than h a c e s of heading 84.17 or 85.14). (I) MACHINES FOR ASSEMBLING ELECTRIC OR ELECTRONIC LAMPS, TUBES OR VALVES OR FLASH-BULBS, l[N GLASS ENVELOPES This group includes : (A) Machines for the vacuum-sealing of lamp bulbs. (B) Rotary machines for the automatic assembly of incandescent lamps or wireless valves. These machines usually include equipment for the heat-treatment of glass (e.g., blowpipes or pressing and closing devices for closing the glass envelope), but remain here even ~f not xncluding such glass-working devices. The heading also includes machinery for assembling electric filament lamps of which the component parts are interconnected by conveyors, and which include e ui ment for the heat-treatment of glass, pumps and lamp-testing units (see Note 4 to Section ~fl The heading does not, however, include machines used solely for making metal parts of components of (e. ., machines for cutting out or de drawing screens, anodes or supports , maefines for spiralling f i e metal wire in %e mufixture of electnc lamp filaments ,and machines for weld~ngscreens or elecfmdes (heading 84.68 or 85.15)). (11) MACHINES FOR THJZ MANUFACTURE OR HOT WORKING OF GLASS OR GLASSWAlU3 The glass-working machines of this and other fused silica) operate mainly b casting, Machines for worZi'ng glass are excluded (heading 84.64). (A) MACHINES FOR THE MANUFACTURE OF FLAT GLASS SHEETS This group includes : (1) Machines for making sheet lass by drawing out flat strips. A roughly formed sheet of glass is picked up by a specia device; it is then gripped b rollers and drawn out vertically or horizontally as it passes through an annealing oven. T e continuous band thus obtained is cut into sheets (mechanically or by an electrically heated wire). f hY (2) Machines for the manufacture of float ass. Jn the float process, the lass is floating horizontally on a molten media, to man actwe an endless glass ribbon, wkch later in the process is cut into pieces. (B) OTHER MACHINES FOR HOT WORKING GLASS This group includes : (I) Bottle-makin machines, etc. These range from sim le mechanical appliances for gathering and lowing (operated by suction or cornpresse air and using separate moulds), to automatic continuous feeder machines (with two revolving plates, one with rough-casting moulds, the other with finishing moulds). (2) S~ecialmachines and presses for mouldin various glass articles (e.g., paving blocks, ti es, insulators, optical glass blanks and ho low glassware), but excluhng presses of general use (heading 84.79). (3) Machines for drawing, shaping or blowing glass pipes or tubes, and special machinery for drawing fused silica tubes. (4) Machines for making ass beads, in particular, machines in which cut pieces of tubing are rounded by being ro ed in rotating heated drums. f (5) Machines for making glass fibre or filaments. These fall into three main categories : (i) Machines for making continuous @ass yarn for weaving. These consist of a small electric furnace which is charged mth glass balls. The bottom of the furnace consists of a draw-plate with a hundred or so very fine holes; the filaments are lubricated as they emerge from these holes, and are joined together by a special device to form a single strand. This is wound on a rotatmg drum which ensures that the filaments are continuously drawn forward. (ii) Machines for making short fibres. These machines are equipped with an electric furaace and a draw-plate like that mentioned above, but there are also sets of converging corn ressed air 'ets on either side. These 'ets fulfil the dual purpose of drawing out an breaking tie filaments. The fibres fa 1 through an oil-spray on to a a suction device inside the drum draws the fibres together to rotating perforated b, form a roving which is wound on to a spool bobbin. a f (iii)Special machines for making glass wadding. The molten glass is poured on to a heated rotating disc; it adheres to the corrugations of the disc and is drawn into fibres by centrifugal action. (6) Machines for bulb-blowing or for making other glass parts of electric light bulbs or tubes, or of electronic valves or tubes, etc. (e.g.,base blocks, filament supports, stems). (7) Machines for making optical fibres and preforms thereof. PARTS to the general provisions regarding the classification of parts (see the General Note to Section XVI), parts of the machines of this heading are classified here. The heading also excludes : (a) Hand type glass blowers (heading 82.05). (b) Certain machines for the manufacture of toughened lass, in which ordinary glass sheets are placed between heated plates and then suddenly cooled (hea ing 84.19). (c) Moulds for manual or mechanical glass-making (heading 84.80). -