Performance Evaluation of a Single Action

8/12/2019 Performance Evaluation of a Single Action

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Journal of Emerging Trends in Engineering and Applied Sciences (JETEAS) 3(5):806-811(ISSN: 2141-7016)

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Performance Evaluation of a Single ActionCassava Peeling Machine

1 O.J Olukunle and 2B.O. Akinnuli

1,Department of Agricultural Engineering.

Federal University of Technology, P.M.B. 704 Akure, Nigeria.2Department of Mechanical Engineering.

Federal University of Technology, P.M.B. 704 Akure, Nigeria.

Corresponding Author:O.J Olukunle___________________________________________________________________________AbstractCassava (Manihot utilissima Pail) is second only to sweet potato as the most important starchy root cropof the tropics among crops grown throughout the tropical world. In most of the tropical world, Cassavais grown on small plot; however, in some countries e.g. Mexico, Brazil and Nigeria, large plantations have

been started and interest in mechanization is growing. The degree of mechanization depends on the size of theland and availability of machine for each unit operations involved in cassava processing. However, of all the

unit operations involve in cassava processing, several process have been mechanized successfully, cassavapeeling remains a serious global challenge to processing Engineers. The purpose of this research is to evaluateeffectiveness of a designed and fabricated single action cassava peeling machine on cassava root cropconsidering difficulties posed by the crops irregular shape, for this reason, a cassava peeling machine withsingle action was fabricated in the Department of Agricultural Engineering, Federal University of Technology,Akure, Nigeria. The capacity of the machine is 1050 kg/h. This machine was evaluated using newly harvestedimproved variety of cassava tuber (TMS30572) grouped into different sizes : 100 L < 140, 140 L < 180, 180 L < 220, 220 L < 260, and 260 L < 300. Machine operational parameters such as machine speed,throughput capacity, peeling efficiency, mechanical damage, quality performance efficiency and peel retentionwere determined for each group size. Results revealed that at high throughput capacity 442 kg/h, peelingefficiency and quality performance efficiency 75 % and 40 % respectively were achieved at high machinespeed 6oorpm for big sizes of cassava range 260 L < 300 but with high mechanical damage 44 % and high

peel retention 33 %. Moreover, at low throughput capacity 76 kg/h, peeling efficiency and quality performanceefficiency 60 % and 50 % respectively were achieved at low machine speed 100rpm for small sizes of cassava

range 100 L


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one that simulates manual peeling by shearing with aknife. An effective cassava peeling machine shouldaccommodate the larger varieties in shapes and sizesof the tubers and should removed all the peels withminimum tuber losses.

Some of these efforts include performance evaluation

of a peeler designed and fabricated by Tamil NuduAgricultural University, Alade (2005) revealed thatthe capacity, peeling efficiency and peel retentionwere found to be 549 kg /h, 59.33 % and 0.572respectively. Production of commercial model of asingle and double gang hand fed cassava peelingmachine at the Department of AgriculturalEngineering, Federal University of Technology,Akure, Nigeria. Olukunle and Adesina (2004). Theresults shown that the maximum machine capacitywas 1000kg/ h compared with 23 kg/h recordedduring manual peeling. Adatan et al (2003) reportedthat some essential tuber properties such as groupaverage diameter, penetration force per unit lengthand peel thickness should be determined in order todesign efficient mechanical peeling system.Olukunle and Oguntunde (2007) reported that soilfactors such as soil type, soil moisture, soil fertility,tillage practices and the vegetation of the farm couldalso influence tuber shape and size. Chemical peelingusing a hot solution of sodium hydroxide to loose andsoften the skin of root which is well developed for

peeling sweet potatoes in processing industriesAdetan et al (2006). A major reason why this methodwill not be suitable for cassava peeling is a highertemperature and more root immersion time will berequired for cassava root because they have peels thatare tougher than those of potatoes.

In Africa and Asia, it has been discovered that mostcassava grower are category of small farm holders

between 0.5 to 5 ha Howeler et al (2004). In view ofthese , there is need to conceive and designappropriate avoidably peeling machine for the cottageindustries in order to meet the processing need of thefarmers. An automated cassava peeling machine isdeveloped at the Department of AgriculturalEngineering, Federal University of Technology,Akure, Nigeria. The aims of this research work wereto generate a design base data for the machine, toestablish relationship between crop, machine andoperational parameters, and also to determinemachine operational parameters for effective peeling

of different sizes of cassava tuber.

METHODOLOGYComprehensive literature research was conducted todetermine machine and operational parameters of asingle action cassava peeling machine. These

parameters include machine speed, throughputcapacity, peeling efficiency, mechanical damage, andquality performance efficiency. Variety used is theIITA's new high yielding tropical manioc selection

(TMS30572) with pest disease resistant ability Ainaet al (2004). This variety is common to local farmersin Africa countries most especially in Nigeria andGhana Oguntunde (2005). Cassava tubers used forthis research work were obtained fresh from a localfarm within the Federal University of Technology,Akure, Nigeria.

Design ConsiderationIn order to make this machine acceptable andaffordable by the concerned users, it was made to: bewithin the buying capacity of local farmers; peeldifferent varieties, shapes and sizes of cassava; madewith readily available materials; reduced the labourinput in traditional method of peeling; and thecapacity was higher compared to manual operations

Machine DescriptionA single action cassava peeling machine consists of aroller with 200 mm diameter and 900mm long. Theshaft is 25 mm diameter runs through the roller.Inclined blade at 70 mm away from each other and at30 angle of inclination mounted on the roller, auger

provided on the roller gives rotary and linear motionon the tuber. Other components include hoper, frame,monitor and chute. It receives torque from 7 HPHonda petrol engine with speed of 1000 2000 rpm.The drive system consists of belt and pulleyarrangement with machine speeds (SP) of 100, 200,300, 400, 500, and 600 rpm respectively. Moreover,variation in speed was achieved by throttling theengine. The rotary motion of the tuber on the bladeeffects the required peeling operations. The monitorserves as guide on tuber in the direction of motion.The capacity of the machine is 1080 kg/h. This gavethis machine an estimated processing time of 0.33seconds/kg.

Cassava Peeling and Washing Machine

Fig. 1.1: Exploded Drawing of the Peeler1---- Hopper 2---- Cover 3---- Brush 4----Brush Pulley 5----Pulley 6---- Frame 7---- Tank 8---- Peeler 9---- Water Pipe10---- Pump 11---- Motor 12---- Chute


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Fig. 1.2: Isometric Drawing of the Processing Unit1---- Linkage 2---- Wheel 3---- Furrow Opener4---- Belt 5---- Furrow coverer 6---Gears

7---- Cutter 8---- Stem tube 9---- Frame 10----Seat

Determination of Machine OperationalParametersThe parameters considered for determination of themachine operations were; speed of Pedy mainlythrough put capacity (Tc), peeling weight proportion(P), peeling efficiency (), mechanical change (),

peel retention (), and quality performance efficiency().

The speed of the peeling machine was recorded inrevolution per minutes. The machine was powered

with 7 HP petrol engine with speed of 1000rpm andconnected peeler to the shaft roller through a belt /pulley arrangement. Six pulleys were used with speed100 rpm, 200 rpm, 300 rpm, 400 rpm, 500 rpm, and600 rpm with their relation diameters of 200, 100, 67,50, 40 and 30 mm respectively.

Throughput capacity Tckg/h = Wt/T (1)

Where Wt = Weight of cassava fed into themachine( kg) andT = Time taken for the cassava and its peel tocompletely leave the machine (h)Length of cassava tuber ( L ) were used as basis for

size range and these were grouped into 100 L


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RESULTS AND DISCUSSIONAuger and monitors introduced into this machine areeffective. The auger provides useful motion bycreating thrust (forward push) for the tuber to be

processed and move out of the chamber after itsresident time while the monitors serve as guide and

provides desire effect on the peeling process. Tubers

were grouped into five sizes and these were analyzed.Operational parameters such as machine speed,throughput capacity, peeling efficiency, mechanicaldamage and quality performance efficiency on eachsize were carried out. Resident time of cassava tuberwas between 5 to 8 seconds in one pass depending onthe augers speed. This influenced peeling efficiency

but not independently of other parameters. Themaximum machine capacity of this machine 1080kg/h (8.64 tons per 8 hours per day) compared with23 kg/h recorded during manual peeling Alade(2005). This value is feasible where average tubersize is up to 1.5 kg. The performance of this machinegave an appreciable improvement on the previousdesigns as well as on the machine presented in 2004at the first Nigeria Universities Research andDevelopment Fair (NURDF) organized by the

National University Commission (NUC) in Abujawith capacity of 5 tons per day Olukunle and Adesina(2004). Figure 1 shown peeled cassava tuber whiletable 1 to 5 shown effect of machine operational

parameters at various sizes of cassava tuber.

Fig. 1: Peeled cassava tuber

Throughput capacity gradually increases as machinespeed increases from 100 rpm to 600 rpm for all sizesof cassava. It also increases as sizes of cassavaincreases as shown in table 1. In other word,throughput capacity is directly proportional to themachine speed and also directly proportional to itssizes.Tc= SP = L 8Peeling efficiency slightly increases as machinespeed increases from 100 rpm to 300 rpm andincreases as cassava size increases for small sizes ofcassava tuber 100 L < 140, 140 L < 180, and 180 L < 220. It slightly decreases as machine speed

further increases from 300 rpm to 600 rpm and

increases as cassava size increases for the same sizesof cassava respectively as shown in table 2. However,

peeling efficiency gradually increases as machinespeed increases from 100rpm to 600rpm andincreases as cassava size increases for big sizes ofcassava tuber 220 L < 260 and 260 L < 300respectively as shown in table 2. In other word, for

small sizes of cassava tuber and at low machinespeeds, the peeling efficiency is directly proportionalto machine speed and directly proportional to itssizes. However, for small sizes of cassava tuber andat high machine speeds, peeling efficiency isinversely proportional to machine speed and directly

proportional to its sizes. Peeling efficiency for bigsizes of cassava is directly proportional to machinespeed and to cassava sizes. SP L (smaller sizes and low speed) (9)

L (small sizes and high speed) (10) SP L (big sizes) (11)

Mechanical damage increases rapidly as machinespeed increases from 100 rpm to 200 rpm and alsoincreases as cassava size increases. It maintainsgradual increase as speed increases from 200 rpm to400 rpm and increases as cassava size increases. Itincreases rapidly as speed of machine increases from400 rpm to 600 rpm and increases as cassava sizeincreases as shown in table 3. In other word, duringcassava peeling operation, mechanical damage isdirectly proportional to machine speed and directly

proportional to tuber sizes. = SP L (12)Quality performance efficiency decreases rapidly asspeed of machine increases from 100 rpm to 600 rpm

and increases as tuber size increases as shown intable 4. In other word, quality performance efficiencyis inversely proportional to machine speed anddirectly proportional to sizes of cassava tuber.

= L (13)Peel retention increases steadily as machine speedincreases from 100 rpm to 300 rpm and slightlyincreases as cassava sizes increases. It suddenlydecreases as machine speed increases from 300 rpmto 400 rpm particularly for small sizes of cassava 100 L


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CONCLUSIONThis cassava peeling machine is an improvementover existing ones and its performance evaluation issatisfactory at various crop sizes. High broken ofcassava was achieved especially at high speed andthis is referred to as mechanical damage and notlosses .This could be considerably adapted as cassava

chips. High throughput capacity and peelingefficiency 442 kg/h and 75 % respectively wereachieved at high speed 600rpm for big size range 260 L < 300 but with high mechanical damage 44 %,high peel retention 33 % and low quality performanceefficiency 40 %. This is as a result of high speed ofthe machine. Moreover, at low throughput capacity76 kg/h, peeling efficiency and quality performanceefficiency 60 % and 50 % were achieved at low speed100rpm for small sizes of cassava range 100 L

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Performance Evaluation of a Single Action