Design Optimization and Development of Portable Magnetic Clamping (MagCLAMP) Based on Machining Performances

Transcription

1 International Journal of Engineering & Technology IJET-IJENS Vol:18 No:01 17 Design Optimization and Development of Portable Magnetic Clamping (MagCLAMP) Based on Machining Performances N. Ab Wahab, Muhamad Suhaimi Bin Jalil, Abd Khahar bin Nordin, A b Hadzley,T. Norfauzi Faculty of Engineering Technology Universiti Teknikal Malaysia Melaka norfariza@utem.edu.my Abstract A machine vice is a clamping device used to hold a workpiece securely when operating a machine tool, such as a drill press or milling machine. However, there are limitation on the thickness of thin material by using the vice that are available in milling machine. The vice can clamp the minimum thickness 3mm and above. The purpose of development of magnetic clamping is to clamp the thin and small part of magnetize material only. The objectives of this study are to develop the magnetic clamping for milling machine. This work is focused on develop a magnetic clamping, modify the design of existing product in the lathe machine that had been develop by the previous student into the milling application. Next, choose the right material in developing the magnetic clamping. It is expected that the results of magnetic clamping can attach the small and thin part on it. This development is a new pattern of magnetic clamping in the faculty. The result of cutting parameter and the surface roughness, Ra was obtained, and the data was tabulate into the table. In the modern work, part getting thinner and small, the convectional vice has the limitation of the minimum thickness. So the magnetic clamping is an additional jig beside vice. Furthermore, certain part or workpiece have small thickness unable to be clamp with normal clamping and require that flat clamping that able to clamp flat surface. The magnetic clamping had been developed by the previous student. But due to some problem the magnetic clamping cannot be function. The objective of this project is to use the existing magnetic clamping to make it function so the purpose to attach the thin part on it can be achieved. For the first the development application is based on the lathe tool room. Index Term Milling, magnet, clamping, vice, magnetic, I. INTRODUCTION Magnetic clampings usually used for fixturing of ferromagnetic material in perfection of switching functions. This magnetic clamping typically uses an electromagnet or permanent magnet to hold the material or workpiece during machining. (Felix and Melkote, 1999). Fig. 1. Convectional vice The main advantage for this magnetic clamping is to make it easy to attach and detach the workpiece and it able to clamp small and thin workpiece. Magnetic clamping also offer several advantages over conventional clamping methods such as vice. Compared with the vice, magnetic clamping produce very little flexible deformation of the workpiece and thus enable limited perspective and form specifications to take place.. This magnetic clamping is in round with the flat working area on the top and an on/off change or key place on the side. Inside the magnetic clamping is a sequence of places that are organized to increase the flux along the outer lining area of the system. Flux is optimized and makes it possible to secure any ferrous materials placed on top of the system by organizing the place in a similar design.

2 II. International Journal of Engineering & Technology IJET-IJENS Vol:18 No:01 18 RESEARCH METHODOLOGY 17mm Fig. 5. Narrow pin shaft and spring Assembly process on the front part. The function of this design is to put the material on it. Then, push the narrow pin shaft that combine with spring. Next, push and rotate the PVC plate right side to unclamp the material. Fig. 6. Assemble of all front part component Fig. 2. Flow chart 2) Rear plate The real part is made up to combine and lock the magnetic clamping to the lathe machine The system CAM shaft is used in this development A. Magnetic clamping In this stage, the magnetic clamping is improved based on the existing magnetic clamping and the machine that available in the laboratory. For the first, the improvement base on the existing magnetic clamping in lathe application Fig. 7. The position of hole Front part Middle part Fig. 8. The CAM lock pin C. The changes of Magnetic Clamping application Rear part Fig. 3. Existing magnetic clamping B. Improvement magnetic clamping design 1) Front part 154mm The changing had been made due to the changing the laboratory and the difference model of the lathe machine in the second laboratory. So the development can not be done. As the chuck on the second lab is bigger than existing magnetic chuck that was refer in the first laboratory 9mm

3 International Journal of Engineering & Technology IJET-IJENS Vol:18 No: mm Fig. 9. Chuck model GH (First lab) Fig. 13. Squaring on the mild steel plate 2. The mild steel material is proceed with facing process that using the end mild diameter 20. The process is likely a drill process. 156mm Fig. 10. Chuck model Opti turn D420 (Second lab) 20mm 30mm Fig. 14. Making the slot on the raw material 154mm Fig. 11. Existing magnetic chuck by refer model Chuck model GH Figure 15 shown the position of holes had be made by referring to the dimension of hole position on the magnetic clamping in Figure 16 Due the changing of the machine application. The improvement on the rear part was change by follow the milling machine. 230mm Fig. 15. Position of hole 155mm Fig. 12. New rear part Fabrication Front plate 1. Raw material mild steel was baught in dimension 235x158x12 and the squaring process had been done. Fig. 16. Dimension of hole position on the magnetic clamping

4 International Journal of Engineering & Technology IJET-IJENS Vol:18 No: Then, the grinding machine was used to get the flatness of the surface. 3mm 3mm 7mm 11mm (a) (b) Fig. 21. (a) Existing magnetic clamping (b) Improvement Fig. 17. Grinding process 5. The CNC router machine had been used to producing the circle shape by using facing process with end mill 4mm D. Assembly 1. Assembly process All the component was put on the table 200mm 200mm 154mm Fig. 18. PVC plate Fig. 22. All the part 6. The lathe machine was use to develop narrow pin shaft Mild steel plate was put on the rear magnetic chuck Fig. 19. facing process Fig. 23. Assemly of rear part 7. The diameter of the narrow pin shaft is referring to the internal diameter of the spring. The allen bolt screw was put on the hole and was tighten Fig. 20. Diamenssion of narrow pin shaft Midle part 1. For the improvement the holes in the existing magnetic clamping need to drill. Fig. 24. Tighten the screw Narrow pin shaft and spring was put on the hole. Fig. 25. the combination of narrow pin shaft and spring was put on the hole

5 International Journal of Engineering & Technology IJET-IJENS Vol:18 No:01 21 F. TESTING USING SURFACE ROUGHNESS The workpieces then tested on its surface roughness using Portable Surface Roughness Tester, SJ-401 as shown in figure 29 Fig. 26. the allen bolt screw was put on the PVC plate to lock it. E. TESTING ON MILLING MACHINE 1) There are five different depth of cut that were testing on the magnetic clamping starting from 0.1mm, 0.2mm, 0.3mm, 0.35mm, 0.4mm. Fig. 29. Portable Surface Roughness Tester, SJ-401 Surface Roughness, Arithmetic average roughness value Ra Ra value Fig. 27. Experimental cutting process 2) The workpiece was done with the cutting process in evaluate the depth of cut. Ra value Point Fig. 30. Depth of cut 0.1mm Surface roughness, Arithmetic average roughness value Ra Point 0.3mm 0.1mm 0.2mm Fig. 31. Depth of cut 0.2mm (a) Fig. 30. Depth of cut 0.3mm 0.4mm 0.35mm For the overall, the conclusion of three different depth of cut are tabulate in the table as easier to compare the result. The graph depth of cut 0.2 are the good among the other in term of the minimum different of largest and smallest and has a minimum mean. (b) Fig. 28. (a) and (b) result of experimental in depth of cut Condition Graph depth of cut 0.1mm 0.2mm 0.3mm Precision Poor Good Moderate Different largest and smallest mm mm mm Mean 0.955mm 0.636mm 0.814mm There are the factor why this result occur. First, the surface of the PVC plate have elastic properties because when the higher force was act on the PVC plate the structure can warp. Also,

6 International Journal of Engineering & Technology IJET-IJENS Vol:18 No:01 22 the flatness testing cannot be done on the PVC. This is because the gauge head are made up from the steel. The gauge head will be influence by the magnetic field. So, this magnetic clamping is need to modified again in the front part only. This development cannot be suitable to machine the precise product. 1. Problem and the solution Arrangement of the magnet Arrangement of need to be correct sequence. Every magnet need to be clarify its poles before located into the magnetic clamping. These poles can be identify by using compass. Magnet is arranged in the slot with alternate position. Fig. 31. Arrangement of the magnet As for result the magnetic are completed develop. There are few difficulty during the development and to solved it. In the term of funtional, the magnetic clamping are able to clamp the magnetize material. There are some suggestions and recommendations for the future work that can improve for this project. Firstly, the material for the front part, in this project PVC material had been used. But it not suitable because when the measure using the dial gauge the value was not constant. For the improvement only unmagnetized material can replace the PVC plate. It because the magnetize material had been used before but fail. The suggestion material is stainless steel 300 series with the thickness 3mm. The stainless steel alloys resist corrosion, maintain their strength at high temperatures and are easy to maintain. They most commonly include chromium, nickel and molybdenum. Stainless steel alloys are used predominantly in the automotive, aerospace and construction industries. This stainless steel is unmagnetized material. So, the accuracy of the flatness on the magnetic clamping can be obtain. The next suggestion, is change the narrow pin shaft and spring with the springer plunger. The spring plungers are designed to provide accurate and controlled spring tension in a piece of equipment, allowing it to work more efficiently. But this arrangement did not work. Although the position of the magnet was at the off position. The magnetic field is strong as the magnet at the on position. By follow the rule of magnet, if the south and south or north and north meet each other the magnetic field will push to another direction. But that did not happen in the development. So, the solution to solve this problem had been made, the concept of the front part was developed. the process or a step to unlock the material. First, the narrow pin shaft and spring was push. Then, the PVC plate was rotate to the right side where the place that are no magnetic field. Next, the specimen or workpiece can easily take out from the magnetic clamping. III. CONCLUSIONS As conclusion, this thesis indicates the design and the development of a magnetic clamping for the milling machine. This study shows the fabrication of a magnetic clamping and determine the functional of the magnetic clamping had been done. The main goal of this study is to produce a new magnetic clamping for the student to exposed on magnetic clamping and understand the mechanism been applied on the magnetic clamping that make its works. ACKNOWLEDGMENT The author would like to thank his supervisor, Dr.Norfariza and Mr. Khahar for providing help and guidance for his bachelor degree project at Universiti Teknikal Malaysia Melaka (UTeM). REFERENCES [1] Beddoes, J., and Bibby, M.J., Principles of Metal Manufacturing Processes. Principles of Metal Manufacturing Processes, pp [2] Singh, R., Introduction to Basic Manufacturing Process and Workshop Technology, Zhurnal Eksperimental noi I Teoreticheskoi Fiziki. [3] J Felix, A., and Melkote, S.N., Effect of Workpiece Flatness and Surface Finish on the Holding Force of a Magnetic clamping. Journal of Manufacturing Science and Engineering, Transactions of the ASME, 121(4), pp [4] Norfariza et.development of Portable Magnetic Clamping for Lathe Machine. ARPN Journal of Engineering and Applied Sciences (Accepted to be published) Fig. 32. The unclamping process