LIQUID/LIQUID, LIQUID/GAS OR GAS/GAS SEPARATION Method General operations by centrifugal force, using centrifuges or free-vortex apparatus using magnetic or electrostatic effect Apparatus General operations by centrifugal force, using centrifuges or free-vortex apparatus , using magnetic or electrostatic effect SOLID/LIQUID OR SOLID/GAS SEPARATION Method General operations by centrifugal force using centrifuges or free-vortex apparatus using magnetic or electrostatic effect Apparatus General operations by centrifugal force using centrifuges or free-vortex apparatus , using magnetic or electrostatic effect SOLID/SOLID SEPARATION Method Dry methods material in bulk Individual sorting Screening, sifting, pneumatic sorting using pneumatic tables or jigs by magnetic or electrostatic effect by centrifugal force using centrifuges or free-vortex apparatus Wet methods General operations flotation, differential sedimentation screening Combinations Dry methods - wet methods Apparatus Dry methods material in bulk Individual sorting Screening, sifting, pneumatic sorting using pneumatic tables or jigs by magnetic or electrostatic effect by centrifugal force using centrifuges or free-vortex apparatus , Wet methods General operations flotation, differential sedimentation screening Combinations Dry methods - wet methods This class does not cover the working of plastics sheet material in a manner analogous to the working of paper, which is covered by class . In this class, the following term is used with the meaning indicated: "plastics" means macromolecular compounds or compositions based on such compounds. In this class, the following rules apply: The working of plastics is, as far as possible, classified primarily according to the particular shaping technique used, e.g. in subclass . A product is not classified in this class unless it results from a technique which is covered by this class. Classification according to production of particular articles in subclass is restricted to: aspects which are characteristic for the production of a particular article, and not classifiable in subclass or ; combined operations for making the particular article which are not fully classifiable in subclass . The codes of subclass are only for use as indexing codes associated with subclasses , , or so as to provide information concerning moulding materials or materials for reinforcements, fillers or preformed parts, e.g. inserts. The codes of subclass are only for use as indexing codes associated with subclass , so as to provide information concerning the articles produced by the techniques classified in subclass . In this subclass, it is desirable to add the indexing codes of subclass . PRETREATMENT Mixing; kneading Conditioning Other pretreatment MAKING GRANULES OR PREFORMS , RECOVERY OF PLASTICS Attention is drawn to Note (3) following the title of class . Layered products or laminating methods are further classified in subclass . In this subclass: repairing of articles made from plastics or substances in a plastic state, e.g. of articles shaped or produced by using techniques covered by this subclass or subclass , is classified in group ; component parts, details, accessories or auxiliary operations which are applicable to more than one moulding technique are classified in groups ; component parts, details, accessories or auxiliary operations which are only applicable or only of use for one specific shaping technique are classified only in the relevant subgroups of groups . In this subclass, it is desirable to add the indexing codes of subclasses and . COMPONENT PARTS, DETAILS ACCESSORIES, AUXILIARY OPERATIONS Moulds or cores Heating, cooling, curing Other features , MOULDING by casting, by coating a mould , Compression moulding by internal pressure Injection moulding Extrusion moulding Blow-moulding Thermoforming OTHER SHAPING TECHNIQUES Bending, folding, twisting, straightening, flattening Stretching Liberation of internal stresses Other techniques JOINING PARTICULAR APPLICATIONS Shaping tube ends Surface shaping Lining or sheathing Shaping composites COMBINATIONS OF SHAPING TECHNIQUES AFTER-TREATMENT REPAIRING Attention is drawn to Note (3) following the title of class . Layered products or laminating methods are further classified in subclass . In this subclass, it is desirable to add the indexing codes of subclass . This subclass constitutes an indexing scheme associated with subclasses , or . In this subclass, the following term is used with the meaning indicated: "rubber" covers: natural or conjugated diene rubbers; rubber in general (for a specific rubber, other than a natural rubber or a conjugated diene rubber, see the group provided for such macromolecular compounds). COMPOSITIONS FOR MOULDING MATERIALS; CONDITION, FORM OR STATE OF MOULDED MATERIAL COMPOSITIONS FOR REINFORCEMENTS COMPOSITIONS FOR FILLERS COMPOSITIONS FOR PREFORMED PARTS This subclass constitutes an indexing scheme associated with subclass .