|
Gravimetric Blender
{{unreferenced, date=March 2010 A gravimetric blender is an item of industrial equipment used in the plastics industry to accurately weigh two or more components and then mix them together prior to processing in an injection molding machine, plastics extrusion, or blow moulding machine. There are two types of gravimetric blender. Loss in weight This type of gravimetric blender measures the "loss in weight" from two or more hoppers using a load cell under each hopper. Material is usually dispensed from the hoppers using a screw conveyor. All materials are dispensed together and the rate of dosing from each hopper is controlled to ensure the correct blend is achieved. Gain in weight (sometimes called a batch blender) A gain in weight gravimetric blender has two or more hoppers arranged above a weigh-pan. These hoppers contain the components which are to be mixed, at the base of each hopper there is a valve to control the dispensing of material from the component hopper into the we ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plastics Industry
The plastics industry manufactures polymer materials—commonly called plastics—and offers services in plastics important to a range of industries, including packaging, building and construction, electronics, aerospace, and transportation. It is part of the chemical industry. In addition, as mineral oil is the major constituent of plastics, it therefore forms part of the petrochemical industry. Besides plastics production, plastics engineering is an important part of the industrial sector. The latter field is dominated by engineering plastic as raw material because of its better mechanical and thermal properties than the more widely used commodity plastics. Companies Markets According to PlasticsEurope, the top three markets for plastics are packaging, building and construction, and automotive. Production Plastics production has been growing globally. The numbers include thermoplastics and polyurethanes, as well as thermosets, adhesives, coatings and sealants and PP-fibe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Injection Molding
Injection moulding (U.S. spelling: injection molding) is a manufacturing process for producing parts by injecting molten material into a mould, or mold. Injection moulding can be performed with a host of materials mainly including metals (for which the process is called die-casting), glasses, elastomers, confections, and most commonly thermoplastic and thermosetting polymers. Material for the part is fed into a heated barrel, mixed (using a helical screw), and injected into a mould cavity, where it cools and hardens to the configuration of the cavity. After a product is designed, usually by an industrial designer or an engineer, moulds are made by a mould-maker (or toolmaker) from metal, usually either steel or aluminium, and precision-machined to form the features of the desired part. Injection moulding is widely used for manufacturing a variety of parts, from the smallest components to entire body panels of cars. Advances in 3D printing technology, using photopolymers that ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plastics Extrusion
Plastics extrusion is a high-volume manufacturing process in which raw plastic is melted and formed into a continuous profile. Extrusion produces items such as pipe/tubing, weatherstripping, fencing, deck railings, window frames, plastic films and sheeting, thermoplastic coatings, and wire insulation. This process starts by feeding plastic material (pellets, granules, flakes or powders) from a hopper into the barrel of the extruder. The material is gradually melted by the mechanical energy generated by turning screws and by heaters arranged along the barrel. The molten polymer is then forced into a die, which shapes the polymer into a shape that hardens during cooling. History The first precursors to the modern extruder were developed in the early 19th century. In 1820, Thomas Hancock invented a rubber "masticator" designed to reclaim processed rubber scraps, and in 1836 Edwin Chaffee developed a two-roller machine to mix additives into rubber. The first thermoplastic extrus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blow Moulding
Blow molding (or moulding) is a manufacturing process for forming hollow plastic parts. It is also used for forming glass bottles or other hollow shapes. In general, there are three main types of blow molding: extrusion blow molding, injection blow molding, and injection stretch blow molding. The blow molding process begins with softening plastic by heating a preform or parison. The parison is a tube-like piece of plastic with a hole in one end through which compressed air can enter. The plastic workpiece is then clamped into a mold and air is blown into it. The air pressure inflates the plastic which conforms to the mold. Once the plastic has cooled and hardened the mold opens and the part is ejected. Water channels within the mold assist cooling. History The process principle comes from the idea of glassblowing. Enoch Ferngren and William Kopitke produced a blow molding machine and sold it to Hartford Empire Company in 1938. This was the beginning of the commercial blow mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Screw Conveyor
A screw conveyor or auger conveyor is a mechanism that uses a rotating helical screw blade, called a "''flighting''", usually within a tube, to move liquid or granular materials. They are used in many bulk handling industries. Screw conveyors in modern industry are often used horizontally or at a slight incline as an efficient way to move semi-solid materials, including food waste, wood chips, aggregates, cereal grains, animal feed, boiler ash, meat, and bone meal, municipal solid waste, and many others. The first type of screw conveyor was the Archimedes' screw, used since ancient times to pump irrigation water. They usually consist of a trough or tube containing either a spiral blade coiled around a shaft, driven at one end and held at the other, or a "''shaftless spiral''", driven at one end and free at the other. The rate of volume transfer is proportional to the rotation rate of the shaft. In industrial control applications, the device is often used as a variable rate f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Masterbatch
Masterbatch (MB) is a solid additive used for coloring (color masterbatch) or imparting other properties (additive masterbatch) to plastics. Masterbatch is a concentrated mixture of pigments and/or additives which is manufactured by encapsulation during a heat process or twin screw extrusion into a carrier matrixresin, which is then cooled and further cut into a granular shape. Masterbatch allows the processor to color raw polymer economically. The alternatives to using masterbatches are buying a fully compounded material (which may be more expensive and less open to e.g. color variability of the product), or compounding from raw materials on site (which is prone to issues with achieving full dispersion of the colorants and additives, and prone to preparing more material than what is used for the production run). In comparison with pure pigments, masterbatches require more storage space and their lead times are longer. Another disadvantage is additional exposure of heat ("heat histo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
