Groundnut stem crop parameters effect on cutting force and energy

Abstract

The harvesting of groundnut crop was done mostly by digging method. After harvesting, the methods to remove the pods from the groundnut crop such as stripping, picking and threshing causes damages and wastage of groundnut vines. The groundnut vines consist of higher protein content that offers effectively supplementary nitrogen to ruminants in dry season. These vines are used as green manure, feed to cattle or combined with other vegetation to produce silage. In order to give importance and avoid the damages and wastages of vines, the groundnut vine cutting machine was developed. To develop the machine, the study was done related to investigating the effect of moisture content, stem diameter and cutter bar speed on cutting force and cutting energy required for cutting of single groundnut stalks. A reciprocating cutter bar test rig was used to measure the cutting force. The test rig consists of main frame, speed drive, cutter bar assembly, power transmission, a load cell and a load indicator. The experiments were conducted at four levels of moisture content (40 - 47, 47 – 53, 53 – 60 and 60 – 71%) (Wet basis), four levels of crop stem diameter (3- 4, 4 –5, 5 – 7 and 7- 8 mm) and four levels of cutter bar speed (0.80 – 0.90, 0.90 – 1.00, 1.00 – 1.10 and 1.10 – 1.20 ms-1). The minimum cutting force of 10 - 20 N and cutting energy of 0.10 – 0.30 J was observed at 60 - 71% moisture content, 3 – 4 mm stem diameter, 1.10 – 1.20 ms-1cutter bar speed. The maximum cutting force of 40 - 50 N and cutting energy of 0.70 – 0.90 J was observed at 40 - 47% moisture content, 7 – 8 mm stem diameter, 0.80 – 0.90 ms-1cutter bar speed. The result shows that cutting force and energy was directly and inversely proportional to stem diameter and moisture content, cutting speed, respectively.