A B C D E F G H I J K L M N O P Q R S T U V W X Y Z All
Hemaprasad, K.
- Analysis of Air Brake used in Medium Duty Truck
Authors
1 Dept. of Mechanical Engg, T. S. Srinivasan Centre for Polytechnic College and Advanced Training, Chennai, IN
Source
Manufacturing Technology Today, Vol 18, No 7 (2019), Pagination: 48-54Abstract
This project work involving modeling and analysis of brake drum of comet vehicle of Ashok Leyland. The work was done using mechanical desktop and Cosmos. The complete brake assembly with about 20 parts was modelled and assembly was created. The assembly is shown below shows the brake shoes, S Cam, cam rod and pneumatic cylinder and slack adjuster. Kinematic analysis was done on the model elements to see interference and limitation of movement. The thrust provided by the shoes on the drum face was computed from the pneumatic pressure under full braking condition and the same was given as a uniform pressure on the brake shoes and the displacement of the drum shell was studied. The maximum deformation of the drum shell was found to be 1.3 X 1o-5 mm.
The stress induced on the drum due to the force applied by the brake shoe was analysed. The stress plat shows the distribution of Y directional stress in the drum when the shoe applies maximum thrust.
Next thermal analysis was carried out on the drum under single application and multiple application of brake with full force. The vehicle inertia was taken when travelling at 60kmph and the brake absorbed the complete energy proportionately by this drum. This energy was applied as heat on the inner face of the drum for the width the shoe is in contact. The decelerating time was computed using empirical formula given by Rudolph Lumpert was arrived at as 10 sec. for deceleration from 60 – 0kmph. The maximum heat flux is applied at time t = 0 and at time t = 10 heat flux applied is zero as there is no braking action while speed is zero. The variation was assumed as linear. As a second alternative the vehicle was accelerated for 40 seconds and braked for 10 sec. And this acceleration and braking cycle was repeated 10 times and corresponding temperature variation was studied on a node on the outer face of the brake drum where convective cooling is taking place during accelerating phase. The curve above shows the temperature variation with reference to time for a period of 370 sec. As can be seen the temperature has not stabilised but increasing. But the cooling curve doing acceleration phase as the temperature difference between ambient and the node is higher.
Keywords
Pressure, Displacement, Deceleration, Thermal Analysis.
References
- Limpert, Rudolf, Brake Design and Safety, SAE Publication, 1999.
- Crowse and Anglin, Automotive Mechanics, Tata Macgrawhill international edition.
- Schulz, Enrich J: Diesel Equipments I, Tata Macgrawhill international edition.
- Heitner, Joseph: Automotive Mechanics, vol. I, East west press.
- Baker, AL: Vechicle braking systems.
- Abel / Desai, Introduction to FEA, CBS publishers.
- Design Data Book, PSG College of Engineering.
- Kirpal Singh: Automobiile Engineering, Standarad publishers.
- Experimental Analysis of Piercing in Titanium Alloy using Abrasive Waterjet Machinei
Authors
1 Dept. of Mechanical Engg, T. S. Srinivasan Centre for Polytechnic College and Advanced Training Vanagaram, Chennai, IN
Source
Manufacturing Technology Today, Vol 18, No 8 (2019), Pagination: 3-20Abstract
Abrasive Water Jet Machining (AWJM) is one of the fastest growing non- traditional machining processes, which uses highly pressurized water mixed with abrasive particles and is capable of cutting even difficult-to-cut materials. It is used in the manufacturing of components with intricate shapes and profiles. Here the experimentation is conducted on abrasive water jet (AWJ) machining of the most commonly used titanium alloy, Ti-6Al-4V. It is significantly stronger than commercially pure titanium while having the same stiffness and thermal properties The machining operations, i.e. drilling (or piercing), were conducted. For the experiments, the influences of water pressure and drilling time, mesh size and abrasive flow rate were investigated.
The experiments are carried out based on Response Surface Methodology (RSM) designed using Box-Behnken method for four parameters into three levels. Using response surface graphs the significant AWJM machining parameters and their levels are identified to achieve depth of cut, hole diameter and kerf width.
Keywords
Abrasive Water Jet Machining, Piercing, Titanium Alloy.References
- Chen, Y; Li, H; Wang, J: Analytical modelling of cutting forces in near-orthogonal cutting of titanium alloy, 'Ti6Al4V. J Mech Eng Sci', vol. 229, no. 6 2015, 1122–1133.
- Wang, J; Guo, DM: A predictive depth of penetration model for abrasive waterjet cutting of polymer matrix composites, 'J. Mater Process Technology', vol. 121, no. 2–3, 2002, 390–394.
- Axinte, DA; Karpuschewski, B; Kong, MC; Beaucamp, AT; Anwar, S; Miller, D; Petzel, M: High Energy Fluid Jet Machining (HEFJetMach): from scientific and technological advances to niche industrial applications, 'CIRP Ann Manuf Technol', vol. 63, no.2, 2014, 751–771.
- Finnie, I: The Mechanism of Erosion of Ductile Metals. Proceedings of the 3rd U.S. National Congress of Applied Mechanics, New York, USA, 1958, 527–532.
- Bitter, JGA: A study of erosion phenomena part I, 'Wear', vol. 6, no.1,1963,5–21.
- Hashish, M: Amodeling study of metal cutting with abrasive waterjets. 'ASME Trans J Eng Mater Technol', vol. 106, 1984, 88–100
- Li, W; Wang, J; Zhu, H; Li, H; Huang, C: On ultrahigh velocity micro-particle impact on steels–a single impact study, 'Wear', vol. 35, no. 1– 2, 2013,216–227
- Seo, YW; Ramulu, M; Kim, D: Machinability of titanium alloy (Ti-6Al-4V) by abrasive waterjets, 'Proc Inst MechEng B J Eng Manuf', vol. 217, 2003, 1709–1721.3
- Fowler, G; Shipway, PH; Pashby, IR: Abrasive water-jet controlled depth milling of Ti6Al4V alloy-an investigation of the role of jet-workpiece traverse speed and abrasive grit size on the characteristics of the milled material, 'J Mater Process Technol', vol. 161, no. 3, 2004, 407–414.
- Shipway, P; Fowler, G; Pashby, IR: Characteristics of the surface of a titanium alloy following milling with abrasive waterjet, 'Wear', vol. 258, no.1, January 2005,123-132.
- Hascalik, A; Caydas, U; Gurun, H: Effect of traverse speed on abrasive waterjet machining of Ti-6Al-4V alloy, 'Mater Des', 28, 2007 1953–1957.
- Wang, J: Predictive depth of jet penetration models for abrasive waterjet cutting of alumina ceramics, 'Int J Mech Sci', vol. 49, 2007,306– 316.
- Hlavac, ML: Investigation of the abrasive waterjet trajectory curvature inside the kerf, 'J Mater Process Technol' vol. 209, 2009, 4154–4161.
- Orbanic, H; Junkar, M:An experimental study of drilling small and deep blind holes with an abrasive water jet, 'Proc Inst MechEng B J Eng Manuf', vol. 218, no. 2004, 503–508.
- Boud, F; Carpenter, C; Folkes, J; Shipway, PH: Abrasive waterjet cutting of a titanium alloy: the influence of abrasive morphology and mechanical properties on workpiece grit embedment and cut quality, 'J Mater Process Technol', vol. 210, 2010, 2197–2205.
- Gent, M; Menendez, M; Torno, S; Torano, J; Schenk, A: Experimental evaluation of the physical properties required of abrasives for optimizing waterjet cutting of ductile materials, 'Wear', vol. 284–285, 2012, 43–51
- A Study of Additive Manufacturing in the Field of Mems Manufacturing
Authors
1 T. S. Srinivasan Centre for Polytechnic College and Advanced Training, Vanagaram, Chennai, IN
Source
Manufacturing Technology Today, Vol 19, No 9 (2020), Pagination: 3-7Abstract
The recent success of additive manufacturing processes in the manufacturing sector has led to a shift in the focus from simple prototyping to real productiongrade technology. Additive manufacturing is a relatively recent manufacturing method which has become a key area of interest in multiple industrial sectors. Deriving from CAD models the process can be used to create solid yet highly complex parts and pushes towards a tool-less manufacturing environment meaning improved quality and better efficiency in many cases. The enhanced capabilities of Additive Manufacturing processes to build intricate geometric shapes with high precision and resolution have led to their increased use in fabrication of Micro Electro Mechanical Systems (MEMS). The Additive Manufacturing technology has offered tremendous flexibility to users for fabricating custom - built components. Over the past few decades, different types of Additive Manufacturing technologies have been developed.
This article provides a comprehensive review of the recent developments and significant achievements in most widely used Additive Manufacturing technologies for MEMS fabrication, their working methodology, advantages, limitations, and potential applications. Furthermore, some of the emerging hybrid Additive Manufacturing technologies are discussed, and the current challenges associated with the Additive Manufacturing processes are addressed. Finally, future directions for process improvements in Additive Manufacturing techniques are presented.