6340(Print), ISSN (Online) Volume 4, Issue 2, March - April (2013) IAEME AND TECHNOLOGY (IJMET)

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1 INTERNATIONAL International Journal of Mechanical JOURNAL Engineering OF MECHANICAL and Technology (IJMET), ENGINEERING ISSN 0976 AND TECHNOLOGY (IJMET) ISSN (Print) ISSN (Online) Volume 4, Issue 2, March - April (2013), pp IAEME: Journal Impact Factor (2013): (Calculated by GISI) IJMET I A E M E DESIGN OF PUNCH AND DIE FOR TAPER ROLLER BEARING CAGE FOR MULTI POCKETING Mr. M. V. ARDESHANA 1, Mr. N. L. MEHTA 2 1 M.E.[CAD/CAM] Student, Department of Mechanical Engineering, B. H. Gardi College of Engineering & Technology, Rajkot, Gujarat, India 2 Asst. Prof. Department of Mechanical Engineering, B. H. Gardi College of Engineering & Technology, Rajkot, Gujarat, India ABSTRACT Taper roller bearing is widely used in the different industries. So there is need to demand for the taper roller bearing. It has four components outer race, inner race cage and roller. The main function of Cage is to maintain rolling element at a uniform pitch, so load is never applied directly to the cage. Cage is manufactured by three ways pressed cage, machine cage, and molded cage. But mostly cage is manufactured by power press. In manufacturing of cage pocketing operation is required as per the number of pockets. In existing situation single pocket is produced in a single stroke of power press. So it has to go for the number of stroke as equal to number of pocket so production time is more for cage manufacturing. In proposed method of manufacturing for cage multi pocketing is performed in a single stroke of power press. Due to that production time for cage is reduced and productivity is increased. Keywords: Cage, Die, Multi Pocketing, Punch, Taper Roller Bearing 1. INTRODUCTION The main function of the roller bearing cage is to avoid direct contact between the rolling elements. At the roller bearings, the cage realizes also the guidance of rollers and at the roller bearings with separable rings the cage retains the rolling elements. [1] Cages function to maintain rolling elements at a uniform pitch so load is never applied directly to the cage and to prevent the rolling elements from falling out when handling the bearing. 367

2 2. EXISTING METHOD OF CAGE MANUFACTURING Pressed cages are usually made of steel, but sometimes of brass, too. They are lighter than machined metal cages. [2] Prone type cage and taper roller bearing cage are manufactured by power press operation. Machined cages of metal and textile laminated phenolic resin are made from tubes of steel, light metal or textile laminated phenolic resin, or cast brass rings. Machined cages are also used where lip guidance of the cage is required. Riveted cage and Prong cage are manufactured by Machine operation. Moulded cages of polyamide are produced by injection moulding and are used in many large-series bearings. Injection moulding has made it possible to realize cage designs with an especially high load carrying capacity. Angular contact ball bearing cage are manufactured by Moulding operation. Cage Drawing: Fig.1. TRB Cage This is the Cage drawing as shown in Fig. In Existing Situation cage is manufactured by Power press. In this cage total no. of pocket is 19. Right now single pocket required single stroke of press so 19 pockets requires 19 stroke per a single cage manufacturing. Indexing mechanism is also required for maintaining proper distance between the two pockets. Production time for a single cage is more. So productivity is less. Production of cage is 6, 00,000 piece per month in a company. To increase the productivity it has to increase the production. Therefore it is required to reduce the production time for a single cage manufacturing. It has to improve the manufacturing process. [2] 3. PROPOSED METHOD OF CAGE MANUFACTURING In propose method of cage manufacturing all 19 pockets produce in a single stroke of a power press. So it can also reduce the production time for the cage. [2] And it can also increase the productivity. Same way there is no need to go for the indexing in cage for producing a pocket. For making all pocket in a single stroke multi pocketing assembly is required. Assembly contains the punch, die, punch retainer, centre pin, die plate, retainer ring. 368

3 3.1. Design of punch and die Here, in this case Blanking Shape is shown in fig. Figure.2. Blanked shape P= Perimeter of pocket=57.8 mm, S=Shear strength = 4000 psi= N/mm 2 T= Thickness of strip = 1.8 mm Force = N (1) 1 tonne = N, So, N = 2.9 tone for 1 pocket. But we have to create 19 pockets in single punching operation. [3] For 19 pocket = = 55.1 tone press capacity required. The clearance is a function of the kind, thickness and temper of the work material, harder materials requiring larger clearance than soft materials, the exception being aluminium. Punch size A1 = mm, Punch size A2 = 9.95 mm, Punch height = mm 3.2. Design of Die The minimum thickness of the die block depends upon the strength required to resist the cutting forces, and it will depend upon the type and thickness of the material being cut. Die thickness=19 mm for blanking perimeter 75 mm Die thickness=25 mm for blanking perimeter 75 to 250mm Die thickness=31 mm for blanking perimeter >250 mm Or die block thickness can be taken as T= cm, F is in tones. So, in this case blanking perimeter is 58 mm so die thickness should be 15 mm. Die size A1 = mm, Die size A2 = mm, Die Height = mm 3.3. Design of Punch Retainer/Holder The main function of punch retainer is to hold the punch. Punch is rest in the slot of punch retainer. Punch holder dimension of the punch holder should be at least 5 mm larger than the punch. Punch holder thickness 25 to 75mm. Punch retainer thickness is 30 mm in this die assembly. It has to rest 19 punches so 19 slots available in the punch retainer Design of Retainer Ring Retainer ring is mounted on the punch retainer. Retainer ring thickness is 25 mm. above the retainer ring it has to provide the constant pressure by bellow or spring. So all punches are together with each other Design of center pin Center pin is fixed with the ram. Center pin is moving inside the punch.so as per constrain center pin outside diameter is 84 mm and below portion diameter is 46 mm. Height 369

4 of center pin is 80 mm. It has outside taper for the proper mating between the outside of center pin and inside of punch. Fig.3. Model of Punch Fig.4. Model of Die Fig.5. Model of Punch Retainer Fig.6. Model of Die plate Fig.7. Model of Centre Pin Punch Retainer Punch Die Plate Fig.8. Model of Retainer ring Center Pin Retainer Ring Die Fig.9. Multi pocketing Assembly Fig.10. Multi pocketing Assembly 370

5 4. ANALYSIS OF PUNCH Allowable stress = yield strength/ factor of safety Factor of safety = 1.5, σ = 2200/1.5 = N/mm 2 (2) Static structural analysis of Punch: Fig.11. Displacement of punch is 0.05 mm Fig.12. Stress analysis of punch Table.4. Result and Discussion Sr. No. Allowable stress Von mises stress N/ mm N/mm 2 From the above analysis we can get the stress developed in the punch is less than the design allowable stress so the design is safe design. 5. CONCLUSION The proposed manufacturing method for cage based on the multi pocketing process. The result for the analysis indicates the safe design for the punch. Multi pocketing assembly include the design for punch, die, punch retainer, retainer ring and centre pin. The main aspect of the multi pocketing is to reduce the production time for the cage but as a by product it can also increase the productivity. REFRENCES [1] Ripanu Marius-lonut,NagitGheroghe, Merticaru Vasile,Husanu Valerica, Lacob Strugaru Sorin Claudiu, Process Quality analysis and monitoring methodology for roller bearings cages stamping, Fascicle of Management and Technology Engineering, Volume XI (XXI)2012,NRI. [2] FAG Rolling Bearing Cages, Designation, Design, Material, TI Nr. WL 95-4 E August

6 [3] Vyankatesh B. Emche and Rajesh R Kandalkar, Efficient Method of Producing Oval Punching holes on Sheet Metal, J Appl Mech Eng 2012, 1:2. [4] Wan Mohd Firdaus Bin Wan Sembak, Design and Fabricate Blanking Die for Tensile Test Specimen, University Malaysia Pahang, November [5] Fuh-Kuo Chen, Bai-Hong Chiang, Analysis of die design for the stamping of a bathtub, Journal of Materials Processing Technology Vol.72 Year1997, Pg. No [6] Cmti Machine Tool Design Handbook (Tata McGraw hill, New Delhi-2007) [7] B. R. Manju, B. R. Manju and V. Sugumaran, Wavelet Design for Fault Diagnosis of Roller Bearings using Continuous Wavelet Transforms, International Journal of Mechanical Engineering & Technology (IJMET), Volume 1, Issue 1, 2010, pp , ISSN Print: , ISSN Online: [8] Vijay Gautam, Parveen Kumar and Aadityeshwar Singh Deo, Effect of Punch Profile Radius and Localised Compression on Springback in V-Bending of High Strength Steel and its Fea Simulation, International Journal of Mechanical Engineering & Technology (IJMET), Volume 3, Issue 3, 2012, pp , ISSN Print: , ISSN Online: [9] Manju B R, A.R. Rajan and V. Sugumaran, A New Wavelet Feature for Fault Diagnosis of Roller Bearings using Decision Tree, International Journal of Mechanical Engineering & Technology (IJMET), Volume 2, Issue 2, 2011, pp , ISSN Print: , ISSN Online: