Design and development of rice straw Chopper-cum-Spreader

Harvesting of paddy which is a major crop of Punjab and is cultivated on an area of about 2.5 million hectares is mostly done by combines. The straw left by combines after harvesting paddy, is difficult to manage as incorporation of straw in the field is highly time consuming and required 6–7 operations. Therefore, fanners opt for burning of paddy straw for quick cleaning of field for sowing next wheat crop as it has limited use. The burning of straw not only causes environmental pollution but also leads to loss of rich organic matter. Thus to solve the problem of paddy straw management in the field, Deptt. of Farm Power and Machinery in liaison with a manufacturer M/s Dashmesh Mechanical Works, Amargarh has developed a tractor operated straw chopper cum spreading machine. The machine in a single operation harvest the stubbles left after combing, chop into pieces and spreads on the ground. The chopped and spreaded stubbles are then easily buried in the soil by the use of single operation of rotavator or disc harrow and decayed after irrigation. Subsequently, wheat sowing is done as usual by the use of strip till drill, no-till drill or traditional drill. Machine consists of a rotary shaft mounted with blades named as flail to harvest the straw and chopping unit consisting of knives. Machine is operated by 45 hp tractor and has 228 cm width of cut. Initial trials on the machine have shown highly encouraging performance. Size of chopped stubbles at flail speed of about 900 rpm and chopper speed of about 1500 rpm was found to vary between 7–10 cm. Cost of the machine is about Rs.40,000/-.