Mehul.K.Modh et al Int J Engg Techsci Vol 2(3) 2011,

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1 Mehul.K.Modh et al Int J Engg Techsci Vol () 011,-5 Design, Improvement and Thrust Bearing Analysis of Oil Expeller Machine Mehul.K.Modh 1*, J.R.Mevada 1 L.C. Institute of Technology, Bhandu,Mehasana, Gujarat, India.. V. Patel College of Engineering, Kherva, Mehasana, Gujarat, India Abstract In this paper we will design and make improvement of some of the components of the oil expeller machine also carried out the thrust ball bearing analysis and results are compared with analytical results. Key Words:Oil Expeller Machine, Design, Thrust Ball Bearing, Ansys, Pro-E 1. INTRODUCTION Screw type oil presses are advanced oil processing machinery, characterized by their high oil output rate with good quality, simple design, easy to use and continuous operation. They can use for various raw materials, such as peanut, beans, rape seeds, cotton seeds, sesame, sunflower seeds, copra etc. According to the online resources, Bamgboye and Adejumo [1] developed an expelling machine for extracting oil from decorticated sunflower seeds. The machine was tested at auger speeds of 0, 0, 50 rpm respectively and three throughputs. Results showed that performance efficiencies increased with auger speed and throughput. Expelling efficiency of over 70% was obtained Alessandra Maria Sabelli [] represented a first step into the development of an extraction tool that maximizes the extraction of oil from moringa seeds, and consequently the consumption of the seeds themselves, not exploited so far. The author designed the press and carried out an experiment to investigate the effect of pressure applied on seed vs. oil extracted (i.e. efficiency of the oil press) Nomenclatures TPD = Tones per Day N = Revolutions per Minute Main Shaft (RPM) N 1 = Revolutions per Minute Motor shaft (RPM) N max = Maximum rotational speed P = Motor Power p = Pressure D 1 = Motor Pulley Diameter D = Gear Box Pulley Diameter T = Main Shaft Torque τ = Shear Stress Fa = Axial or Thrust Force M = Minimum axial load factor Cdyn = Dynamic Capacity of Bearing The uses of various investigational techniques were described and illustrated with examples of work by D. Scott of the National Engineering Laboratory. [] Also methods of diagnosis of impending bearing failure and its prevention are outlined. The main objective of this work is to design and improvement by replacing the existing bearing. Also carry out analytical and software analysis of thrust ball bearing used in machine.. PRODUCT DESIGN Fig.1. Double Chamber Oil Expeller Machine Fig.. Location of Thrust Ball Bearing IJETS

2 Mehul.K.Modh et al Int J Engg Techsci Vol () 011,-5.1 Problem Description 1. Thrust ball bearing of m/c fails once in to months.. Type of failure It breaks into pieces. Technical Details These details are taken from the machine catalogue 1. Steam rate Kg/Cm. Quantity to be crushed 5 to 0 TPD. Main Shaft rotation N = RPM. Motor rotation N 1 = 90 RPM 5. Motor Capacity 85 HP. Thrust bearing No (ZKL Company) 51 M 7. Pr. required expelling oil from mustard seeds MPa to 15 MPa. 8. Motor Pulley Dia. D 1 = 0 mm 9. Gear Box Pulley Dia. D = 00 mm. Calculate Gear Ratio and Verify Main Shaft Rotation [] Find input speed for Gear Box For belt drive D1 N = D N1 0 N = N = 5. RPM For Gear Drive T D Gear Ratio G 1= = T D 5 8 G= 1 = = 18 1 T5 Similarly, G= = =.5 T 18 Gear Ratio G = G 1* G = *.5 =.5 Main Shaft Rotation N = I/P speed at Gear Box * Gear Ratio G N = 5. *.5 N = 1.8 RPM Say N = RPM. Main Shaft Design. [] 1 HP = KW Motor Power P = 85 HP P =.15 KW NT Power P= 0 * * T.15 * = 0 T = 7.8 * N m = 7.8 * N mm Shear Stress for 5C8 Steel [0] τ u= 500N/mm Say =150 N/mm τ *d * τ Now Torque T= 1 *d * 150 = 1 Main Shaft Dia. d = mm Say d = 1 mm.5 Small Chamber Design [] T = 7.8 * N mm = F * r = F * 55 = 7.8 * N mm IJETS 7

3 Mehul.K.Modh et al Int J Engg Techsci Vol () 011,-5 F N F F 50.18* N Pr.= = =10 N/mm = A *d *L *10*L h Where, d h = Warm s core diameter Pr. = Pressure required to expel oil from mustard seeds MPa to 15 MPa. Hence taking Pr. = 1 Mpa = 10 N / mm (1 MPa = N / mm ) Length of Chamber L = 8. mm Take L = 850 mm F F 50.18* N Pr.= = =10 N / mm = A *D* D d *D* D 10 Chamber inner Dia. D = mm Take D = 170 mm h Fig.. Small Chamber Casing Fig.. Warm inside the Chamber BEARING DIAGNOSIS.1 Minimum Axial Load Required [5] At higher rotational speeds danger of ball sliding between ring raceways can occur because of centrifugal forces, if axial load Fa drops under minimum value. Minimum value Fa is calculated from equation: Fa min = M (N max / 00) [KN] Fa min =. ( / 00) = [KN] Where, (Refer Table1) Fa min minimum axial load [KN] N max maximum rotational speed [min -1 ] M Minimum axial load factor If the axial load is smaller than Fa min, or if bearing relieving comes into being during operation, e.g. of one ball row in double direction bearing, or of one bearing when using a pair of single direction thrust bearings, it is necessary to secure minimum load, e.g. by means of springs.. Calculate Thrust Load [] *D * P * 170 *0 Thrust Load Fa= KN= * Fa =.85 KN Calculate Nominal Thrust Bearing Life for Bearing No 51M Thrust Bearing Life, (/) L = * C dyn / Fa 0 * (/) L = * 7 /.85 0 * L = 75 hrs L = days Lh = 5. Months Here we get the life of bearing 5. months but actually when machine is operated hours its designed life should be 50 to 0 Kh. So it is desirable to select a newer bearing with the desired life. (Refer Table ). Bearing Selection Process Calculate the dynamic load rating, C dyn For the required bearing life. Identify candidate bearings with required rating Select bearing with most convenient geometry, also considering cost and availability IJETS 8

4 Mehul.K.Modh et al Int J Engg Techsci Vol () 011,-5 Step 1 Select the bearing life of years = 80 hrs (See the Table No ) Thrust Bearing Life L = * C dyn / Fa 0 * (/) C dyn = 57.9 KN Step Identify candidate bearings with required rating Bearing no 51 is selected C dyn = 7 KN (See table No 1) Table 1 Bearing Data [5] 80 hrs= * C /.85 0 * (/) dyn Table Bearing-Life Recommendations Table [5] Sr. Type of Application Life, Kh 1 Instruments and apparatus for infrequent use Up to 0.5 Aircraft engines 0.5 Machines for short or intermittent operation where service interruption is of minor importance 8 Machines for intermittent service where reliable operation is of great importance Machines for 8-h service which are not always fully utilized 1 0 Machines for 8-h service which are fully utilized Machines for continuous -h service Machines for continuous -h service where reliability is of extreme importance Bearing Analysis Result and Discussion Fig.5. Analysis of Right side race in Pro e and Ansys work Bench (Selected Fig Only) IJETS 9

5 Mehul.K.Modh et al Int J Engg Techsci Vol () 011,-5 ANALYTICAL SOLUTIONS.1 Formulas for Right Side and Left Side Races [7] Left Side Race Area= d 1 d Right Side Race D D1 Principle Stress Area= P σ = A Axial Deformation or Displacement l δl Principle Strain e= L Pl Strain Energy P*l δ = A*E.1.1 Sample Calculation for Left side race of 51M Bearing Area of Left Race = d1 - d A = 0 A.77 mm P 0* Principle Stress σ = = = 9.01N/mm A.77* Axial Deformation or Displacement P*l 0* *5 - δ l = = =1.1179* mm 5 A*E.77* *.08* - δl * -5 Principle Strain e =.718 L 5 - Pδl 0* *1.1179* Strain Energy = = = 0.09N/mm A *.77*.1. Formulas and sample calculations for Ball Part [7] Area= (Diameter of Contact Surface with Race Groove) Diameter of Balls is 5mm and 50 mm and groove are 11 mm and 1 mm respectively for old and new bearings Principle Stress Where Deformation d I= Principle Strain P σ = A P r δ= E I δ e= r Using these equations values of stress, strain, deformation and strain energy are calculated and plotted into the Results Tables.1. Sample Calculation for Ball part of 51M Bearing Area = (Diameter of Contact Surface with Race Groove) IJETS 50

6 Mehul.K.Modh et al Int J Engg Techsci Vol () 011,-5 Area = (11) A = mm P Principle Stress σ = = = N/mm A d * (5) I = = =7. mm P r 18.57*(17.5) Deformation δ= = = mm 5 EI.08* *7.* δ Principle Strain e= = =.858* r 17.5 Pδl 18.57* Strain Energy = = = 0.08 N/mm A *9.985.Results Table Comparison of results obtained by Ansys and Pro-E for old and new bearing Analytical Software Analysis Property Old New Ansys Pro E Bearing Bearing Old New Old 51M 51M Bearing Bearing Bearing Left Side Race Maximum Principle Stress New Bearing Displacement (X Axes) E E Maximum Principle Strain.718E-05.15E E Strain Energy E Right Side Race Maximum Principle Stress Displacement (X Axes) E E Maximum Principle Strain.118E-05.57E E E-07 Strain Energy.885E E Ball Maximum Principle Stress E Displacement (X Axes) 5.79E- 5.E E E- Maximum Principle Strain.858E- 7.07E E- 1.E- Strain Energy CONCLUSIONS In this dissertation work we designed some of the components of oil expeller such gear ratio, main shaft rpm, main shaft diameter and crushing chamber dimensions. Design of all these components matches with the components actually used in oil expeller machine. Therefore we can say that the design components used is safe. We also calculated the thrust force acting upon the thrust ball bearing, which is quite high which a bearing can withstand. Calculated life of existing bearing is about 5. months. Hence new bearing must be selected and hence we select bearing no 51M which gives satisfactory life of.5 years by calculation. This bearing has been also replaced by the company and it is giving satisfactory result and has not failed yet. Further we have done static analysis of the Part of bearing on Pro-E wild Fire and Ansys Workbench 11. In analysis results the Principle stress, Principle strain and axial deformation is reduced. Further the results obtained by different software are approximately matching the results obtained by the analytical solutions. From the comparison of the result data we found that results obtained by the Ansys Workbench are closer to the analytical results. IJETS 51

7 Mehul.K.Modh et al Int J Engg Techsci Vol () 011,-5.0 REFERENCES [1] Bamgboye and Adejumo, Development of a Sunflower Oil Expeller, Agricultural Engineering International: the CIGR E-journal, Manuscript EE 0 015, Vol IX. September, 007 [] Alessandra Maria Sabelli, "Design of a Press for Oil Extraction from Moringa Seeds for Haiti" Thesis, Department of Mechanical Engineering, Massachusetts institute of technology, January 00 [] D. Scott, Bearing failure Diagnosis and Investigation, Nationall Engineering Laboratory, East Kilbride (Gt. Britain), Vol Wear 5, Page No 199-1, 197 [] R.S. Khurmi and J.K. Gupta, A Text Book of Machine Design, Chapter 1 Shaft and Chapter 7 Rolling Contact Bearings, 1th edition, 005 [5] ZKL Bearings, Thrust Ball Bearings, Manual Page No [] Flender Extruder Ltd, Selection Process Manual, K1-1.0 EN, 005 [7] Indrajeet M. Jain, Advanced Strength of Materials, Tech Max Publication, Chapter 1, Page No 1-8 IJETS 5