Theses

Browse

Search Results

Now showing 1 - 9 of 11

Open Access
Design fabrication and testing of an arecanut dehusker
(Department of Farm Power Machinery and Energy, Kelappaji College of Agricultural Engineering and Technology,Tavanur, 1993) Febi Varghese; KAU; Jippu Jacob
A power operated arecanut dehusker is designed, developed and its performance evaluated. The major parts are the hopper, feeder, lead plate, cutting blade, shearing roller, friction plate and scraper. The feeder receives the graded fruit from the hopper and delivers it on the lead plate. The fruit is compressed between the rotating shearing roller and the lead plate. The teeth on the roller peel off the husk and the kernel is ejected out through the slot on the lead plate and the husk removed. A single phase 0.5 hp motor operates the machine. From the studies, the optimum set - up of the machine for deriving maximum dehusking efficiency and Iower percentage of the number kernels damaged is at a speed of 35 rpm, blade angle of 600 and slot angle of 1400. At this set - up the machine gives an output of 9.0 kg dried fruit/h, with 84.5 per cent dehusking efficiency.
Open Access
Evaluation and modification of powertiller operated paddy reaper
(Department of Farm Power Machinery and Energy, Kelappaji College of Agricultural Engineering and Technology, Tavanur, 1995) Selvan, P; KAU; Sivaswami, N
The study on power tiller operated paddy reaper-windrower was taken up solve the problems of labour scarcity and uneconomic cost of cultivation of paddy. The 1.6 m vertical conveyer reaper-windrower was fabricated and was mounted with commercially available 8-10 hp air cooled Mistubishi power tiller. Improvements and modifications were carried out to make the unit suitable for harvesting of paddy in Kerala. The original engine chasis of the power tiller was replaced with a newly fabricated chasis on which both the engine and paddy harvester were mounted. Difficulties were experienced in starting and in operating the harvester when the drive was taken directly from the engine pulley to the cutterbar. Initialy the unit was operated with rotovator at the rear side. It was found difficulty in crossing the bunds, hence rotovator was removed. After detailed studies, an auxiliary gear box was designed and fabricated for transmitting power to reaper from the rotovator gear assembly. The rear rotovator was dismantled and the auxiliary gear box was assembled. For balancing, a counter weight of 35 kg was added in between the handles. The crop is cut by the reciprocating knife while passing through crop dividers, star wheels, pressure springs and is conveyed by a pair of lugged conveyer belts and is discharged as a neat windrow. Improvements and modifications were carriedout on most of the reaper components. Field evaluation of paddy harvester was carried out at KCAET Tavanur for two seasons. It was found that harvester has an effective cutting width of 1.55 m and an average field capacity of 0.02036 ha/hr. The pre harvest loss, sickle loss, shattering loss and total cutter bar loss were found to be 0.005 per cent, 2.43 per cent and 0.026 per cent respectively. The power tiller operated reaper-windower was found suitable for harvesting paddy both in wet as well as dry fields except the fully lodged crops. It is an appropriate machinery for harvesting paddy and is found economically and technically suitable for Kerala conditions. It was calculated that manual harvesting needs Rs. 1625/ha whereas power tiller operated reaper needs only Rs. 348/ha and thus achieved a saving of amount of Rs. 1277/ha. The savings of 186 man-hrs/ha achieved by the introduction of power tiller operated paddy reaper is a promising solution for the crisis of labour scarcity and the high cost of labour input in the paddy cultivation.
Open Access
Design, development and testing of a transplanting mechanism for conventional paddy seedling
(Department of Farm power and Machinery, College of Agricultural Engineering,Ludhiyana, 1979) Cheeram Parambil, Muhammad; KAU; Verma, S R
For over half of the world’s population, rice provides the main dietary source of energy and hence is one of the most important food materials. In the Far – East, where 90 per cent of world’s rice is grown, transplanting is widely practised due to numerous advantages offered by this method. Manual transplanting being a rather tedious operation, paddy transplanters had been developed and introduced in several countries notably Japan. Transplanters using conventional seedlings, however, are still receiving world wide attention as the commercial transplanters such as in use in Japan were costlier and employed special type of nursery raised with much care and skill. It was, therefore, decided to develop and test a new type of paddy transplanting mechanisms, with the following specific objectives: 1. To design and develop a mechanisms for transplanting conventional paddy seedlings 2. To test the transplanting mechanisms under laboratory conditions 3. To identify the important parameters of the mechanism and establish their range for optimal operation of the unit designed under objective (1). Accordingly, a paddy transplanting mechanisms was designed and developed. Attempts were made to overcome, as far as possible, the drawbacks of similar mechanisms already developed and reported. It was a single - row unit with provision to add more such units, as as to make a multi - row machine with a row - spacing of 20 cm. It was designed to transplant washed - root seedlings of 20 to 30 cm length at a hill to hill distances of 15 cm, with 2 to 3 seedlings/hill, to a depth of 3 to 4 cm, with not more than 5 per cent missing hills and 1 per cent seedling damage. Made mainly of M. S. and supported on a wooden float, the mechanism weighted 9.5 kg without seedlings. The important components of the mechanism were a seedling box to hold the seedlings, a seedling rake and seedling ejector for positive conveyance of the seedlings into the picker – jaws, a pair of picker sets mounted on the main shaft and actuated by a stationary cam to pick and release the seedlings, and a planting finger to plant the seedlings, laid horizontally on the ground after release, by the pickers. The main shaft was rotated by a ground wheel, as the mechanism was drawn forward by manual, animal or tractor power. In order to study the effect of reduced tip velocity of the pickers, another mechanism with four picker-sets, based on the same concept as the first one, but with proportionately larger dimensions of pickers and stationary cam, was also fabricated. The components like seedling box, rake, ejector and main shaft were retained with the same specifications as for the mechanism with two picker - sets. This mechanism weighed 11.75 kg against 9.5 kg for the first mechanism. The mechanism with two picker sets was designated as mechanism – A and that with four picker sets as mechanism – B for convenience. The two mechanisms were tested in the laboratory to compare their performance in respect of the plant hill missing, seedling damage, seedling distribution, average number of seedlings per hill and the power consumption. The tests were conducted with 4 rates of picking, i.e. 60, 90, 120 and 150 hills/min and 3 seedling heights i.e. 30, 25 and 20 cm for both mechanism A and B. The laboratory tests revealed that as the rate of picking increased from 60 to 150 hills/min, the missing hills increased from 4.09 to 16.8 per cent and 6.95 to 16.44 per cent; seedling damage from 0.8 to 1.43 per cent and 0.53 to 0.89 per cent; and power consumption from 13.6 to 33.6 and 17.1 to 42.1 watts for mechanisms A and B respectively. The average number of seedlings for both the mechanisms studied, decreased from 2.4 to 2.0 for 30 cm long seedlings as the rate of picking increased from 60 to 150 hills/min. However, upto a picking rate of 120 hills/min, the missing hills were 5.69 and 10.69 per cent for mechanisms A and B respectively, as against the desired 5 per cent missing hills. Seedling damage was less than 1 per cent and average number of seedlings/hill was above 2.00 in both the mechanisms with a variation of 0 to 8 seedlings/hill with a maximum standard deviation of 1.32. As the seedling height was reduced from 30 to 20 cm, the average number of seedlings/hill was found to increase from 2.36 to 2.55 at the rate of picking of 60 hills/min, 2.11 to 2.39 at 90 hills/min, 2.07 to 2.39 at 120 hills/min and 1.99 to 2.09 at 150 hills/min. At all seedling heights, upto 120 hills/min, the average number of seedling/hill was above 2.00, which was within the required limit. On comparing the performance of the two mechanisms, it was found that there was no difference between the two regarding their ability to pick the number of seedlings/hill. However, missing hills were more in mechanism B as compared to mechanism A. For a rate of picking, upto 120 hills/min mechanism A had acceptable missing hill of 5.69 per cent as against the recommended 5 per cent, while mechanism B, had 10.67 per cent which was considerably higher than the acceptable limit. The seedling damage, upto 120 hills/min rate of picking was under 1 per cent for both the mechanisms. Limited field trials revealed that the planting finger provided in the mechanism did not function satisfactorily and as such the plants were not properly planted. Deposition of mud on the stationary cam and seedling ejector was a problem noticed in the field. Consequently, the free rotation of the main shaft was hampered which in turn led to the skidding of the ground wheel. This called for further improvements in the design of the planting finger and groundwheel drive. It was concluded that mechanism A could pick the seedlings from the seedling box and release them satisfactorily on the ground upto a picking rate of 120 hills/min. The missing hills and seedling damage were within acceptable limits. Trouble – free working of the transplanter fitted with such mechanism would have a capacity of about 0.0216 ha/hr per row. The forward speed for the rate of picking viz. 120 hills/min comes to about 1.08 kmph. The mechanism could not plant the seedlings erect and improvement on planting finger was needed. About 125 man – hrs/ha were required to wash and load the seedlings and if a 4-row bullock drawn version could be used, it would require about 140 man-hrs/ha as against 200 to 250 man-hrs/ha in hand transplanting. This would justify further developmental efforts and refinement of the mechanism.
Open Access
Design, development and evaluation of a power tiller operated bed former
(Department of Farm Power Machinery and Energy, Kelappaji College of Agricultural Engineering and Technology, Tavanur, 1991) Shaji James, p; KAU; Sankaranarayanan, M R
A power tiller operated Bed Former was developed and evaluated. The main components of the prototype unit of the power tiller operated Bed Former are, a main frame, two pairs of forming boards, a leveling board, a hitching unit and a depth control cum transport wheel. The equipment was found capable of forming seed beds of heights 22 cm, 18 cm and 15 cm at a width range of 60-64 cm. Heights of 18 cm and 15 cm were possible at width ranges of 73-75 cm and 80 – 81 cm. The draft of the implement ranges from 115.59 kgf to 169.69 kgf. The power utilization of the implement varies from 0.586 hp to 0.771 hp and the wheel slip between 46.76 per cent and 77.1 per cent. The mean effective field capacity of the implement is 0.0996 ha/hr and the mean field efficiency is 46.3 per cent. The total cost of production of the unit is Rs. 2000/- and the cost of operation per hectare is Rs. 777/-. The amount that can be saved by using the implement is Rs. 1473/- per hectare.
Open Access
Fabrication and testing of a low cost flat plate collector-cum-storage solar water heater
(Department of Farm Power Machinery and Energy, Kelappaji College of Agricultural Engineering and Technology, Tavanur, 1990) Lissy, Kirian; KAU; John Thomas, K
The study was conducted with the objectives of developing and testing the Collector – cum storage type solar water heater to evaluate its performance. The collector – cum storage heater was consisted of a concrete tank with dimensions 150 x 70 x 10 cm and had a capacity of 100 litres of water. An absorber plate of size 152 x 72 cm was made of Aluminium sheet and was fixed into the tank. The front face of the absorber sheet was painted black to absorb maximum solar radiation. Glass cover was fixed at the top, leaving an optimum air gap of 40 mm. The heater was inclined to the latitude of Tavanur and was oriented to south for collecting maximum solar radiation. The solar water heater was filled daily at 8 am with fresh water. The performance of the water heater was observed from 20th October 1989 to 26th January 1990. Optimum inclination of the heater was found to be 100 52’ 30”. The water heater was found to attain a maximum outlet temperature of 520 C at 3 pm. Efficiency of the heater was calculated to be 51%. Solar intensity meter read a maximum solar flux of 1120 w/m2 at 12 O’clock in the month of October. The heater can supply 100 litres of hot water at 50 – 520 C at a very reasonable cost of Rs. 777.5. The cost per unit of thermal energy obtained with this water heater is 8 paise per kwh. There is a remarkable break – through in its cost and performance as compared to a conventional natural circulation type solar water heaters.
Open Access
Studies on selected manually operated pumps
(Department of Farm Power Machinery and Energy, Kelappaji College of Agricultural Engineering and Technology, Tavanur, 1990) Geeta Susan, Philip; KAU; John Thomas, K
The study was conducted with the objective of evaluating hydraulic and ergonomic performance of some selected manually operated pumps viz. Kirloskar pump, Kumar Bharath pump, E.P. pump (Lift), E.P. pump (Force) and Bicycle operated diaphragm pump. A subject was selected for the study and his body surface area was calculated. Heart rate was taken as the measure of mechanical work load on the subject and he was calibrated for the basic task. From the calibration curve it was found that heart beat of the subject should not exceed 110 beats/min for the ergonomic safety. Pumps were tested against different suction heads by varying the position of the gate valve connected in the suction line. Discharge, speed of operation, time of operation and heart rate of the subject were noted. Hydraulic characteristics of the pumps were analysed by studying the discharge, time to deliver 100 1, number of strocks to deliver 100 1, and volumetric efficiency with variation in head. Ergonomic features were analysed by studying the variation of heart rate with head. Among the five pumps the volumetric efficiency of Kumar Bharath pump reduced below 75% beyond the head 6.9 m corresponding heads for the other pumps are 6.7 m for Kirloskar, 5.8 m for E.P. pump (Force) 5.7 m for E.P. pump (Lift) and 1.1 m for diaphragm pump. Time to deliver 100 1 and number of strokes to deliver 100 1 were highest in the case of diaphragm pump and least in Kumar Bharath and Kirloskar pumps. Taking hydraulic and ergonomic performance into consideration the following heads can be recommended for the pumps. Kumar Bharath 6.6 m, Kirloskar 5.25 m, E.P. pump (Lift) 5.7 m, E.P. pump (Force) 5.8 m and diaphragm pump 1.1 m corresponding discharge of the pumps are 0.23 1/s, 0.37 1/s, 0.3 1/s, 0.45 1/s, 0.45 1/s respectively.
Open 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.
Open 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.
Open 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.

Theses

Browse

Thesis Type

Type

Author

Date

Subject

Search Results