Track laying

84.29 - Self-propelled bulldozers, angledozers, graders, levellers, scra em, mechanical shovels, excavators, shovel loaders, tamping machines and road rol ers. P - Bulldozers and angledozers : 8429.11 - - Track laying 8429.19 8429.20 - - Other - Graders and levellers - Scrapers 8429.40 - Tamping machines and road rollers - Mechanical shovels, excavators and shovel loaders : 8429.51 - - Front-end shovel loaders 8429.52 - - Machinery with a 360' revolving superstructure 8429.59 - - Other 8429.30 The heading covers a number of earth di ging, excavating or compacting machines which are ex licitly cited in the heading and wP;~ c hhave in common the fact that they are all se f-propelled. f The provisions of Explanatory Note to heading 84.30 relating to self- ropelled a$ multi-function machines ap 1 , mutatis mutandis, to the self-propelled mac inery of thls heading, which includes the o lowing : E !? (A) Bulldozers and angledozers. These consist of a propelling base, often track-laying, with a large blade mounted in front, and forming an inte a1 mechanical unit. They are used, in articular, for removin debrjs and for rough level ing. Certain types are designed mainly for grubbing or for lan clearing. Y d (B) Graders and levellers. These are machines designed for earth levelling or smoothing (on flat surfaces or banks) by means of an adjustable grading blade, usually mounted within the wheel base. (C) Sera en. These incorporate a sharp cutting edge desi ed to slice off a layer of top soil whic is then passed into the scraper body or discharge by a conveyor. p g It should be noted that this heading covers only those scrapers in which the motor propulsion unit and the scraper form an integral mechanical unit, for example, track-laying scrapers in which the scraper body incorporating the cutting edge is situated between the two tracks. This headin also includes articulated scrapers which consist of a motor m ulsion unit (even w i g only a single axle and a scraper proper equipped with a fixed Elale or a mobile attachment with several bl es. d (D) Tampin machines as used in road making, for packing rail-road ballast, etc. (but see paragrap (a) of the introduction to Explanatory Note to heading 84.30 regarding machines mounted on vehicles of Chapter 86). %. ropelled road rollers as used in road building 0 level self-f?ing the ground or rolling the road surface). or other public works (e.g., for These machines are fitted with heavy cast iron or steel cylinders of large diameter, smooth or studded with metal feet which press into the soil (" sheep's-foot" rollers), or with wheels and heavy grade solid or pneumatic tyres. (F) Mechanical shovels (boom, jib or cable type) which dig into the soil, above or below machine level, by means of an excavating bucket, ab, etc., operated either directly from the end of a boom or ~b(shovel excavators, drag s ovels, etc.) or, to increase the working range, on a cable or y means of a hydraulic jack suspended fiom the jib (&a lines). In long range excavators (slackline draglines), the bucket is operated on a cab e running between two movable structures set some distance apart. E= d k (G) Multi-bucket excavators in which the digging buckets are fitted on endless chains or on rotating wheels. These machines ofien incorporate conveyors for dischargin the excavated soil, and they are mounted on wheeled or track-laying chassis. Special mode s are designed for digging or cleaning out trenches, drainage channels, ditches for use in open-cast (open-p~t)mines, etc. ? (H) Self-propelled shovel loaders. These are wheeled or crawler machines with a front-mounted bucket which pick up material through motion of the machine, transport and discharge it. Some " shovel-loaders " are able to dig into the soil. This is achieved as the bucket, when in the horizontal position, is capable of being lowered below the level of the wheels or tracks. (IJ) Loader-transporters used in mines. These machines, the main firnction of which is handlin and not transport, are equi ped with a fiont-mounted bucket which picks up bulk materia fs and discharges them into i e body of the machine. This heading also covers self-propelled shovel loaders having an articulated arm with a bucket, mounted on the rear. PARTS the general provisions regarding the classification of parts (see the General Note to Section XVI), arts of the machines of this heading, in particular, working buckets, etc.), whetl? er or not fitted with booms and pneumatic or hydraulic for mounting directly onto the propelling base, are classified in heading 84.31.