7 and usa 28 in india there are three common ways of

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Europe 20-40%, Japan 39%, South Africa 16%, England 17.7% and USA 28%). In India, there are three common ways of getting rid of plastics - by dumping them in landfills, by burning them in incinerators or by littering them. In the case of littering, plastic wastes fail to reach landfills or incinerators. It is the improper way of disposing plastics and is identified as the cause of manifold ecological problems [2]. Extrusion plays a prominent part on the plastics industry. Plastics extrusion is a high-volume manufacturing process in which raw plastic is melted and formed into a continuous profile. Extrusion is a continuous process, as opposed to moulding, which is a cyclic process. Approximately 65% of all plastics in use today pass through an extruder [4]. In more recent times, a number of companies are selling composite railroad ties manufactured from recycled plastic resins, and recycled rubber. Plastic/Composite ties (P/C ties) can be made of recycled plastics, generally polyethylene, but often include other materials such as steel fibre, steel reinforcing bar, shredded used tires, mineral filler, virgin plastic, or concrete. The modelled representative P/C tie is assumed to be 8% virgin HDPE plastic, 7% talc (mineral filler), and the balance a mixture of post-consumer recycled milk bottles, grocery bags, and tires. Electric energy is required to process the mixture and extrude the P/C product. The spacing of the P/C product and the required steel used to fasten the P/C tie to the track are assumed the same as creosote-treated crossties [5]. 2. Design Aspects The design concept consists the following: a) Maximum volume of the melt needed to fill the mold. This entails length of the screw conveyor ( l ), diameter of the barrel ( d ), melt density (ρ m ) and melt mass ( m ); b) Design of barrel which entails diameter of the barrel. c) Design for screw conveyor. While the design analysis entails the following units: a) The Extruder unit comprises of the hopper, barrel, band heater, nozzle, screw conveyor, bearing housing and gear box b) The clamping unit consists of the mold and clamping for locking device. c) The electrical panel comprises of temperature control box, and thermocouple. 3. Machine Construction The major techniques employed in construction of the designed machine include machining operation on lathe machine, drilling operations on drilling machine, boring operation on lathe machine, keyway cutting on slotting machine, flame cutting using oxyacetylene gas welding machines, grinding for good finishing, electric welding using arc welding machine. Basically, these constructional techniques were broken down into four sub-heading
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namely; cutting operation, machining operation, welding operation and assembly; and finishing operation.
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  • Fall '19
  • Compressive strength, Plastics. Thermoplastics

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