Article presents a structural analysis of connecting rod of driving mechanism of separator with eccentric belonging to technical equipment of harvesting rhizomes ofMiscanthus, where the equivalent tension values in structure and resulting relative movement are determined. Within the mechanism which drives the separator with eccentric, the connecting rod of quadrilateral mechanism is subject to tensile strength and compression.Structural analysis of connecting rod belonging to eccentric separator has allowed the optimization of its construction and operation

MARIN, E.

SORICA, C.

SORICA, E.

Annals of the University of Craiova - Agriculture, Montanology, Cadastre Series

Analele Universităţii din Craiova, seria Agricultură – Montanologie – Cadastru (Annals of the University of Craiova - Agriculture,Montanology, Cadastre Series)Vol. XLVI 2016555STRUCTURAL ANALYSIS OF CONNECTING ROD OFSEPARATOR DRIVING MECHANISM WITH ECCENTRICBELONGING TO TECHNICAL EQUIPMENT FOR HARVESTINGMISCANTHUS RHIZOMESSORICĂ C.1), MARIN E.1), SORICĂ E.1),1)INMA Bucharest;E-mail: cri_sor2002@yahoo.comKeywords:structural analysis, connecting rod, optimization,  separator with eccentricABSTRACTArticle presents a structural analysis of connecting rod of driving mechanism ofseparator with eccentric belonging to technical equipment of harvesting rhizomesofMiscanthus, where the equivalent tension values in structure and resulting relativemovement are determined..Within the mechanism which drives the separator with eccentric, the connecting rodof quadrilateral mechanism is subject to tensile strength and compression.Structuralanalysis of connecting rod belonging to eccentric separator has allowed the optimization ofits construction and operation.INTRODUCTIONFor establishing a new culture, using a high quality material is a prerequisite andtherefore, rhizomes harvesting represents one of the most important operations [2], [3], [8],[9], [10] with major influence on the quality of seedling material.Technical equipment of harvesting Miscanthus rhizomes (fig. 1) performs theoperation of extraction of Miscanthus rhizomes out of the soil and their separation of earth.Process of displacement consists in soil deep loosening without overturning it, destroyingthe connections between soil and rhizomes and pushing them up to the oscillating grates;the grates separate by sieving the rhizomes of impurities and earth and let them in thefurrow, after which they are loaded into the transport means.Equipment comprises aseparator with eccentric driven by a quadrilateral mechanism made of  a connecting rod, acrank and a working beam, represented by separator’s rods.The separator with eccentric is driven by a hydraulic engine coupled at the tractor’shydraulic installation.Fig. 1 – Equipment for harvesting the Miscanthus rhizomes [11]Main technical characteristics of technical equipment for harvesting Miscanthusrhizomes are shown in table 1:Analele Universităţii din Craiova, seria Agricultură – Montanologie – Cadastru (Annals of the University of Craiova - Agriculture,Montanology, Cadastre Series)Vol. XLVI 2016556Table 1Den.no. Characteristic MU Value1. Type of equipment - carried2. Type of displacing plough share - plane inclining blade3. Driving method of separator with eccentric - hydraulic4. Separator oscillation frequency Hz 4.165. Amplitude of separator’s oscillations mm 266. Power of tractor working in aggregate HP 70...807. Working width m 1.28. Working depth cm max. 259. Clearance mm 350Separator with eccentric (fig. 2) is designed to clean the earth by shaking andtransport the Miscanthus rhizomes displaced to the machine’s rear part. It comprises twooscillating grates that take over the soil displaced together with the rhizomes and anoscillating mechanism with eccentric that achieves an optimum vibrating effect so that thesoil detaches from rhizomes and fall on the ground between the grate holes.Fig. 2 – Separator with eccentric [11]MATERIAL AND METHODThe driving mechanism of separator with eccentric which is a component part oftechnical equipment for harvesting Miscanthus rhizomes is a quadrilateral system (fig. 3)made of: crank 1, connecting rod 2, working beam 3 and four rotation couplings (R).Fig. 3 – Scheme of quadrilateral mechanism that drives the separator with eccentric [11]Analele Universităţii din Craiova, seria Agricultură – Montanologie – Cadastru (Annals of the University of Craiova - Agriculture,Montanology, Cadastre Series)Vol. XLVI 2016557Within the driving mechanism of separator with eccentric, the quadrilateralmechanism connecting rod is subject to strain forces if the separator’s angular speed(mechanism connecting rod) has negative sign ω3< 0 and compression, if the angularspeed of separator has positive sign ω3> 0.Following the kinetostatics analysis, reactions of each rotation coupling of themechanism have been obtained. Therefore, it has found that the maximum tensile strengthis manifested for the position of mechanism at which the crank rotation angle is φ1 = 4.538rad. For this position, the tensile force acting on point B has the value of R12=2105,829 Nand tensile force acting on point C has the value of R32=1980,821 N. [11]Maximum compression forces become manifest for the mechanism position atwhich the crank rotation angle is φ1 = 1.221 rad. For this position, the compression forceacting on point B has the value of R12=1095,24 N and, the compression force acting onpoint C has the value of R32=2191,273 N.Taking into account these strains, it has found that the maximum stress is presentwhen stretching for the crank rotation angle of φ1 = 4.538 rad. and structural analysiswillbe based on this strain.Geometry of connecting rod is generated in SolidWorks program and shown infigure 4.Fig. 4 – Connecting rod geometryStructure is made of two solid components considered to be totally connected andworking together as a unique body. Meshing is made with elements of 3D type (fig. 5) andcontains 114203 elements and 172865 nodes.Type of structural analysis is the linear static elastic analysis and therefore thematerial out of which is made the structure is an elastic-linear, homogeneous and isotropicmaterial. The connecting rod position comparing to coordinates system is that at which it isplaced at the maximum stress moment.Structure is loaded in the two bearings, each bearing being acted by a tensile strength withtwo components on axes OX and OY (fig. 6).Structure is made of steel with the following material constants:- density 7800 kg/m3;- limit  strain 220,59 MPa;- limit breaking tension 399,83 MPa.Analele Universităţii din Craiova, seria Agricultură – Montanologie – Cadastru (Annals of the University of Craiova - Agriculture,Montanology, Cadastre Series)Vol. XLVI 2016558Fig. 5 – Structure meshingFig. 6 – Structure loadingAnalele Universităţii din Craiova, seria Agricultură – Montanologie – Cadastru (Annals of the University of Craiova - Agriculture,Montanology, Cadastre Series)Vol. XLVI 2016559RESULTS AND DISCUSSIONSAnalysis results have consisted in indicating the values of equivalent tension instructure and relative movement resulted. Relative movement resulted represents animportant parameter of structure deformation. For the agricultural machines designed tosoil works, a high value of structure deformation can determine an inappropriate quality ofagricultural works.Equivalent tension [1], [4], [5], [6], [7], is the measure of tension in metallicstructures that is used for comparing it to the limit strain related to each it must be smaller,in order to operate in the elastic field. Distribution of equivalent tension in structure isshown in figure 7, and that of relative movement is shown in figure 8.Fig. 7 – Distribution of equivalent tension in structureMain results of linear static analysis are synthetized in table 2.Table 2Equivalent tension,[MPa]Relative movement resulted(deformation), [mm]Maximum value 56.8 0.027Analele Universităţii din Craiova, seria Agricultură – Montanologie – Cadastru (Annals of the University of Craiova - Agriculture,Montanology, Cadastre Series)Vol. XLVI 2016560Fig. 8 – Distribution of relative movementCONCLUSIONS Due to the fact that maximum equivalent tension (56.8 MPa) is much smaller than thelimit stretching tension of material (220.59 MPa), the whole structure works within thelinear elastic domain; In conditions considered, the most stressed area is in the joint connected to the crank thatdrives the mechanism, to the strain force resultant direction.(fig. 7); Maximum relative movement (fig. 8) takes place in the joint connected to the crank thatdrives the mechanism, its maximum value being of 0.027 mm; For the structure loaded the minimum value of safety coefficient is of 3.88, value whichis appropriate to joint structures of agricultural machines.REFERENCES1. Ahrendts, J. and &, 1995 –Engineer Manual (Hutte. Die Grundlagen derIngineurwissenschaften), EdituraTehnică Publishing, Bucharest;2. Atkinson, C. J., 2009 – Establishing the perennial energy crops in Great Britain: Areview of current options of Miscanthus propagation, biomass and bioenergy, Volume 33,No.5, Pg.752–759.3. Boersma, N. N., Heaton, E. A., 2014 – Method of propagation affecting Miscanthus- xmorphology of giganntic development, Industrial cultures and products, Volume 57, June2014, Pg.59–68.4. Buzdugan, Gh., 1980 – Materials’ Resistance, EdituraTehnică Publishing, Bucharest;.5. Comănescu. A., Suciu. I., Weber, Fr., Comănescu, D., Mănescu, T., Grecu, B.,Miklos, I., 1982 – Mechanics, Materials’ Resistance and working parts,EdituraDidacticăsiPedagogică Publishing, Bucharest;6. Iacob, C., Gheorghiţă, I.S., Soare, M., Dragoş, L., 1980 – Mechanics dictionary,EdituraStiinţificăşiEnciclopedică Publishing, Bucharest.Analele Universităţii din Craiova, seria Agricultură – Montanologie – Cadastru (Annals of the University of Craiova - Agriculture,Montanology, Cadastre Series)Vol. XLVI 20165617. Marin, C., 1997 – Materials resistance and elements of elasticity theory,EdituraBiblioteca Publishing, Târgovişte;8. O’Flynn, M. G., Finnan, J. M., Curley, E. M., McDonnell, K. P., 2014 – Diminishing thecrops damaging and yield losses in the last harvesting period of Miscanthus × giganteus,Researches on soil and harvest, Volume 140, Pg.8–19;9. Sorică, C., Voicu, E., 2009 – Development of a technology capitalizing the Miscanthusrhizomes in order to make more efficient the establishment of this energy culture, Contractno. 15N/27.02.2009, Project: PN 09-15.02.01;10. Sorică, C., Voicu, E., Manea, D., 2009 – Technology for  promoting in Romania theenergy plant Miscanthus as a renewable source for increasing work competitiveness andsafety, in INMATEH Journal No. 29 (2009-III), pg. 19-26, Bucharest, ISSN 1583-1019,http://www.inma.ro/inmateh;11. Sorică, E., 2014 – Theoretical contributions to working process of technical equipmentof harvesting Miscanthus rhizomes, Paper no. 3, Doctoral School.

STRUCTURAL ANALYSIS OF CONNECTING ROD OF SEPARATOR DRIVING MECHANISM WITH ECCENTRIC BELONGING TO TECHNICAL EQUIPMENT FOR HARVESTING MISCANTHUS RHIZOMES

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STRUCTURAL ANALYSIS OF CONNECTING ROD OF SEPARATOR DRIVING MECHANISM WITH ECCENTRIC BELONGING TO TECHNICAL EQUIPMENT FOR HARVESTING MISCANTHUS RHIZOMES

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Annals of the University of Craiova - Agriculture, Montanology, Cadastre Series