In agricultural farm machinery, polymers are widely used for many applications. In recent years many agricultural farm implements are adopting polymer based plastic parts like seed dill ferule roller, weeding equipment, star wheel of harvester, vegetable planter hopper, zero till drill flute, animal yoke, maize sheller, diary vessels etc as a step towards value engineering. By varying the synthetic blend component and its miscibility with starch, the morphology and hence the properties can be regulated easily and efficiently. Blends containing thermoplastic starch (non crystalline starch) may be blended or grafted with biodegradable polyesters, such as polycaprolactone, to increase flexibility and resistance to moisture. Blends mainly formed into films and sheets, thatare used for foaming and injection molding. By mixing thermoplastic starch with cellulose derivatives, rigid and dimensionally stable injection molded articles result. Seeding and weeding in paddy is an essential component in paddy production. There are many models of seeders and single row conoweeders available in the market which are being used for mechanized seeding and weeding operation. These are basically made with Mild Steel which has certain disadvantages in terms of mach- inability, reproducibility, weight, life, appearance etc. An improved manually operated 8-row drum seeder (plastic moulded) for direct sowing of pre-germinated paddy for wetlands and plastic mouldedconoweeder developed was evaluated for its performance in various farmers field. It was observed that the cost of production of plastic moulded eight row drum seeder and plastic moulded cones for conoweeder was almost on par to that of these equipment made with MS sheet. Field studies revealed that plastic moulded seeder and conoweeder recorded higher field capacity, seeding/ weeding index and performance index over implement made of MS, with lower working forceand plant damage. The ergonomic study revealed that heart beat/min, VO2/min, ODR score, body part discomfort score, OCR as VO2 max, per cent of plastic moulded equipment was found better over metallic model of equipment. This clearly gave an indication that there is a scope for substitution of MS material by polymers in rice mechanization. This paper deals with production process and performances evaluation of plastic mouldedconoweeder for wet land paddy production.

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@article{mohanncrtam011014,
title = "Role of Polymer in Weeding and Seeding Machinery in Agriculture Rice Mechanization ",
journal = "International Journal of Science and Engineering Applications (IJSEA)",
volume = "NCRTAM",
number = "1",
pages = "59 - 64",
year = "2013",
author = " M. Mohan, G. Sundararaj, Ravindra Naik, A.R. Soman ",
}