EFFECT OF BLADE TYPE ON POWER REQUIREMENT AND PUDDLING QUALITY OF A ROTAVATOR IN WET CLAY SOIL

The effect of type of blades on power requirement of a tractor drawn r otary cultivator during puddling in Bangkok clay soil was investigated . For this purpose,'C'-shaped, 'L'-shaped and a combination of 'C' and 'L' blades called 'C-L' blades were used. The PTO torque was measured by a PTO drive torque transducer and the power consumed was calculate d for each blade attachment. The puddling quality was assessed in term s of percentage reduction in bulk density and puddling index. Tests we re conducted al different forward speeds of 1.0, 1.5 and 2.0 km/h. To study the effect of passes, three rotavator passes were given. It was observed that 'C'-shaped blades consumed less power than 'L' and 'C-L' blade attachments at any forward speed and pass. The 'L' blade attach ment required 33%, 24% and 14%, while the 'C-L' blade attachment requi red 14%, 12% and 4% higher power than the 'C' blade attachment during the pass 1 at 1.0, 1.5 and 2.0 km/h forward speeds, respectively. The power consumed decreased at higher passes. For air blades, power durin g the Ist pass was higher than the other two passes. For the 'C' blade , the per cent reduction in bulk density and the puddling index was hi gher compared to the per cent reduction in bulk density and puddling i ndex obtained with 'L' and 'C-L' blade rotavators. In general, the 'C' blade performed better than the other two types investigated in this study.