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  • ThesisItemOpen Access
    Development of a power operated black pepper thresher
    (Department of Farm Power Machinery and Energy, Kelappaji College of Agricultural Engineering and Technology, Tavanur, 1998) Suma Nair; KAU; Jippu Jacob
    A power operated black pepper thresher comprising mainly of a threshing drum and a concave; both lined with thermofoam, was developed. It was driven by a O.S-hp, 3-phase, variable speed motor. Pepper spikes were fed into the thresher and the threshed material from all the outlets were collected and separated into berries, damaged berries, unthreshed spikes, partially threshed spikes, and partially threshed spikes with unthreshed berries. The weights of all the fractions were recorded. The values of the threshing efficiency, the percentage of damaged berries, and the capacity were calculated. A three-factor factorial experiment was conducted taking the feed rate, the peripheral velocity, and the contact length as the independent variables, and the threshing efficiency, the percentage of damaged berries, and the capacity as the dependent variables. From the analyses of data, it was seen that all the independent variables exerted significant influence on the threshing efficiency, the percentage of damaged berries, and the capacity. In general, threshing efficiency showed an increasing trend atincreased feed rates for all the different contact lengths. It was most influenced by the peripheral velocity. Threshing efficiency was found to peak around 300 m1min. beyond which it showed a decrease. The percentage of damage was observed to be higher at higher feed rates and lower peripheral velocities. The values of percentage of damage was only between 0.05-0.55 %, which indicated that the therrnofoam assisted in reducing damage to the berries. The capacity showed an increase with the feed rate. However, it did not vary much as the contact lengths were changed. The capacity generally increased with increase in peripheral velocity. A multiple regression equation was developed for the prediction of the power requirement. The maximum power requirement of 0.46 hp was at a feed rate of 50 kglh and a peripheral velocity of 296.9 m1min. The cost of threshing using this thresher was only Rs 1.42 per kilogram, showing that the thresher was very economical. It was highly cost effective compared to the cost of manual threshing which is Rs 6.01 per kilogram.
  • ThesisItemOpen Access
    Development and performance evaluation of a black pepper skinner
    (Department of Farm Power Machinery and Energy, Kelappaji College of Agricultural Engineering and Technology, Tavanur, 1996) Anandabose, D; KAU; Jippu Jacob
    A power operated black pepper skinner was developed, tested and its performance evaluated. The major parts were two cylinder – concave assemblies, a hopper, a feed roll, an inclined belt separator assembly and a variable speed electric motor with a speed reduction unit of 10:1 ratio. The decortications took place as a result of the compressive and the shearing forces acting upon the pepper berries fed between the rotating drum and the stationary concave. A 3 – factor, Factorial Experiment in Completely Randomized Design (CRD) with feed rate, drum speed and surface condition as factors was adopted. The maximum overall decorticating efficiency was observed at the feed rate of 12 kg/h and drum speed of 20 rpm for both the surface types. The maximum decorticating efficiency observed for coir-mat was 91.5 and that observed for rubber surface was 94.2. The effectiveness of wholeness of kernels was found to show lower values for the highest speed of 25 rpm due to the crushing of berries. The maximum overall decorticating efficiency recorded for coir – mat was 87.7 per cent and that recorded for rubber sheet was 90.3 per cent. The study showed that the parameters of feed rate, drum speed, and surface type, have significant influenz on decorticating efficiency, effectiveness of wholeness of kernals and overall decorticating efficiency.
  • ThesisItemOpen Access
    Evaluation and modification of spike-tooth and rasp-bar type paddy threshers
    (Department of Farm Power Machinery and Energy, Kelappaji College of Agricultural Engineering and Technology, Tavanur, 1993) Sailaja, L; KAU; Sivaswami, M
    The field survey conducted on the threshing practices of paddy in Kerala revealed that the hand beating method which is more common in southern part of Kerala needed 154.7 man h/ha with an average output of 18.5 kg/man h requiring an amount of Rs. 823.5/ha whereas, in central Kerala the feet rubbing method required Rs. 1599.0/ha and needed only319.8 man h/ha with an average output of 11.27 kg/man h. The 8 hp axial flow spike-tooth type and 10 hp flow through rasp-bar type threshers were evaluated and found an average output of 50 kg/hp h and 107 kg/hp h respectively. The maximum threshing efficiency of 98.77 per cent and 97.44 per cent were recorded for the flow through rasp-bar thresher during ‘virippu’ and ‘mundakan’ seasons compared to only 95.50 per cent and 94.49 per cent respectively for spike-tooth thresher. The high moist and long paddy crops used to stick and choke in between cylinder and concave clearance and hence the concave was successfully improved to eliminate these problems. The improved concave also improved the output to 1081 kg/h and 1122.6 kg/h with an increase of 9.25 per cent and 4.27 per cent respectively during ‘virippu’ and ‘mundakan’ seasons. A maximum output of 305.7 kg/hp h was obtained for the 1 hp prototype thresher with the rasp-bar cylinder compared to the output of 256.5 kg/hp h for spike tooth cylinder. The cost of operation for the commercially available axial flow through rasp-bar threshers was found to be Rs. 400/ ha and Rs. 207/ ha respectively. The rasp-bar thresher with improved concave could save an amount of Rs. 616.5/ha which accounted to a net saving of 74.9 per cent in the cost of threshing compared to the hand beating method.
  • ThesisItemOpen Access
    Development and testing of a manually operated paddy dibbler
    (Department of Farm Power Machinery and Energy, Kelappaji College of Agricultural Engineering and Technology, Tavanur, 1992) Bini Sam; KAU; Sankaranarayanan, M R
    A manually operated three row paddy dibbler for dry sowing was developed and tested at Kelappaji College of Agricultural Engineering and Technology, Tavanur. The metering mechanism employed in this dibbler was unique in design. The machine consists of seed box, roller with metering mechanism, seed tube with furrow opener, frame, handles and marker. When the dibbler was operated for dibbling, the roller passing vertically through the centre of box would move upward by the soil pressure against the spring pressure. As the roller moved upward, the portion of the roller having the vertical slot would come in contact with seeds and the seeds were moved and carried to this slot. When the equipment was taken out from the soil, the soil pressure on the roller was released and due to the spring pressure the roller moved downward and the seeds carried in the slot were released and would fall through the seed tube by gravity in to the soil. During the operation of the equipment due to the downward travel of the roller and seed tube the seed hole was created for dropping the seeds. The covering of seeds with soil was carried out automatically when the equipment was taken out from the soil. The number of seeds dropped was in the range of 4 to 6 per hill. The area covered by the dibbler was 0.022 hectare per hour. The field efficiency obtained was 68.68 per cent. The mechanical damage was 4.84 per cent. The percentage losses of seeds after germination was 9.52. The fabrication cost of the dibbler including cost of material was Rs. 800/-. The operating cost of the dibbler was Rs. 16/- per hour. The cost of sowing one hectare of land was Rs. 717/- while for manual dibbling the cost of sowing was Rs. 979/- per hectare. Moreover manual dibbling is done in a bending position which is arduous to the farmer. But in the present design of dibbler, a suitable handle is provided which ensure easy and comfortable operation in a straight posture. The equipment can be fabricated locally with readily available materials and can be easily maintained by small farmers.
  • ThesisItemOpen Access
    Development and evaluation of a low cost power operated paddy thresher-cum-winnower
    (Department of Farm Power Machinery and Energy, Kelappaji College of Agricultural Engineering and Technology, Tavanur, 1996) Sureshkumar, P K; KAU; Sankaranarayanan, M R
    Since threshing is labour intensive and involves considerable human drudgery and as the threshers now available are not suitable for small and marginal farmers, a Low Cost Power Operated Paddy Thresher Cum Winnower has been developed and tested. The machine consists of a threshing unit of wire loop cylinder and cover, a winnowing unit, a grain collecting tray, prime mover, power transmission system and the main frame. The power required to operate the machine is taken from a 2 hp electric motor and is transmitted to the cylinder and blower shafts by V- belt and pulley arrangement. Two labourers can hold the crop against the threshing cylinder. The optimum cylinder speed is 400 rpm. The capacity of the thresher at 16.0 per cent moisture content of the crop is 300 hg per hour. Threshing and cleaning efficiencies are 99.25 and 91.82 per cent respectively. Mechanical damage to the grain is negligible. The labour requirement of the thresher cum winnower is two. The cost of the thresher cum winnower was found out to be around Rs 8000.00 and the cost of operation for threshing and winnowing was Rs 8.50 per quintal. An empirical relation between the energy requirement of the thresher and various crop and thresher parameters is P = 931.035 + 4.683 (MC) – 0.462 (PV) – 1.169 (FR) + 8.251 (G/S ratio) The moisture content of the crop and the Feed Rate have statistically significant effect on power Requirement whereas the cylinder speed and Grain/Straw ratio do not have any statistically significant effect.
  • ThesisItemOpen Access
    Development of a power tiller operated paddy transplanter for conventional seedlings
    (Department of Farm Power Machinery and Energy, Kelappaji College of Agricultural Engineering and Technology, Tavanur, 1995) Prakash, K V; KAU; Sivaswami, M
    Transplanting of paddy seedlings is a very tiresome and labour consuming operation and labour shortage is experienced during planting. As a solution to reduce the high cost of cultivation and labour shortage in paddy transplanting, a power tiller operated paddy transplanter is an essential need of hour. The APAU paddy transplanter was evaluated after rectifying the defects at KCAET instructional farm, Tavanur. Based on the field experiences and considering the all problems in APAU paddy transplanter, an improved version of power tiller operated paddy transplanter was developed and fabricated at KCAET Tavanur and tested during September-October 1994. The convensional root washed paddy seedlings ready to manual transplanting were used. When the power tiller is operated at a forward speed of 1.20 km per hr, the transplanter could transplant 2 to 4 seedlings per hill at a spacing of 100 to 120 mm. The average field capacity was found to be 0.13 ha per hr. A saving of Rs.800 per ha which is 50 per cent and reduction of 296 man-hr per ha which is 92.5 per cent was achieved for transplanting operation alone compared to manual transplanting.
  • ThesisItemOpen Access
    Design fabrication and testing of a cashewnut decorticator
    (Department of Farm Power Machinery and Energy, Kelappaji College of Agricultural Engineering and Technology, Tavanur, 1993) Joby Bastian; KAU; Jippu Jacob
    A manually operated cashewnut decorticator is designed, developed and evaluated. The major parts are top blade assembly, and linkage assembly, 2-blade bottom assembly, and linkage assembly. The whole assembly is fixed on a work table. The steamed cashewnut is placed manually between the top and bottom blades. Upon pressing the pedal the top and bottom blades slit the two long sides of the nut. The two bottom blades are then opened wide with a cam splitting open the shell in to two halves. The kernel is released from the shell. The efficiency in decorticating is 88 per cent while the percentage of the number of kernels damaged is 12. The capacity of the machine is 900 nuts/h. The important physical properties of nuts were also studied. It is kidney shaped. Its mean size is 32.40 mm long, 24.60 mm wide and 17.60mm thick. The average kernel size is 26.00 mm long, 17.20 mm wide and 12 mm thick. The average thickness of the shell is 3.20 mm. The average weight of the nut is 7.0 g while that of the kernel is 2.1 g. considering its performance the mechanism is sound. It is recommended for further studies and modifications.
  • ThesisItemOpen Access
    Modification and testing of KAU Arecanut De-husker
    (Department of Farm Power Machinery and Energy, Kelappaji College of Agricultural Engineering and Technology, Tavanur, 1996) Rajmohan, C K; KAU; Jippu, Jacob
    An arecanut dehusker consisting of mainly a pair of fluted rollers, a pressure roller assembly, a scrapper assembly, a guide chute and a feed tray was developed in this study. The arecanut was fed between the two counter- rotating fluted rollers and was pressed against these rollers by the pressure roller. The fluted rollers gripped the husk and pulled it to the rear side of the rollers. In the process the husk was ripped open and the kernel was ejected from its shell. The performance of the machine was studied at speeds of 60, 90,120,150 and 180 rpm and with three different surface characteristics of the rollers. The surface characteristics of the rollers were varied by having different number of teeth and pitch. From the studies the optimum setup of the machine for deriving maximum dehusking efficiency and minimum damage to the dehusked kernels and unhusked fruits was obtained. This was at a speed of 150 rpm against the roller surface having 30 teeth with pitch 3.9mm, width 2.0mm, and depth 1.0 mm. At this set-up the dehusking efficiency, percentage of the number of dehusked kernals and unhusked fruits damaged were 94.4, 5.5 and zero percent respectively. And also this set-up yielded an output of 23 kg of arecanut kernals per hour.
  • ThesisItemOpen Access
    Development and quality evaluation of thermally processed jackfruit (artocarpus heterophyllus L.)
    (Department of Post Harvest Technology and Agricultural Processing, Kelappaji College of Agricultural Engineering and Technology,Tavanur, 2012) Pritty S, Babu; KAU; Sudheer, K P