Informatics Publishing Limited

G. Gopala Krishna ¹, P. Ram Reddy ², M. Manzoor Hussain ³

Affiliations
1 Department of Mechanical Engineering, J.B. Institute of Engineering and Technology (Autonomous), Yenkapally, Moinabad Mandal, Hyderabad-500 075, Telangana, IN
2 JNTU, Hyderabad, Telangana, IN
3 JNTUH College of Engineering, Sultanpur, Medak District, Telangana, IN

Abstract

Nowadays, aluminium and aluminium alloys are most widely used in many applications in which the combination of high strength and low weight is attractive. Friction Stir Welding (FSW) process is an efficient and cost-effective method for welding aluminium and aluminium alloys. FSW is a solid-state welding process in which the material is not melted during the process. Being a solid state process it overcomes many welding defects that usually happens with conventional fusion welding techniques which were initially used for low melting materials. Though this process is initially developed for low melting materials but now the process is widely used for a variety of other materials. In this present experimental investigation, initially, butt joining of similar aluminium alloy AA6351 with AA6351 and dissimilar aluminium alloy AA6351 with AA5083 of 5 mm thickness were carried out by FSW and compared tensile properties. To study the influence of another element such as copper and brass on both combinations have been carried out. FSW has been done by inserting 0.1 mm thickness of copper and brass foil separately in butt joint position for both similar and dissimilar aluminium alloy combinations by changing the rotational speed of the tool. Tensile properties studied for all these combinations and results were compared using with and without foil of copper and brass material.

Keywords

Friction Stir Welding, Tensile Properties, Aluminium Alloys AA6351 and AA5083, Copper and Brass Materials.

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N. L. Narayana , N. V. S. Raju , K. Chaithanya , P. Ram Reddy , M. Rajesh

Abstract

Failure mode, effects and criticality analysis (FMECA) is an extension of failure mode and effects analysis (FMEA). FMEA is a bottom-up, Inductive analytical method which may be performed at either the functional or piece-part level. FMECA extends FMEA by including a criticality analysis, which is used to chart the probability of failure modes against the severity of their consequences. The result highlights failure modes with relatively high probability and seventy of consequences, allowing remedial effort to be directed where it will produce the greatest value. The objective of FMECA is to identify all failure modes in a system design. Its purpose is to find all critical and catastrophic failures that can be minimized at the earliest.

Keywords

Criticality Analysis, Failure Mode, Failure Effects, Risk Priority Number, Etc

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K. Thirupathi Reddy ¹, P. Ram Reddy ², P. V. Ramana Murthy ²

Affiliations
1 Department of Mechanical Engineering, RGM College of Engineering & Technology, Nandyal-518501, IN
2 J.N.T University, Hyderabad, A.P, IN

Abstract

The objective of this study was to evaluate the various properties of biodiesel and optimize the biodiesel blend with conventional diesel fuel. Biodiesel fuel is a clean-burning fuel made from natural renewable sources such as free fatty acid of rice bran vegetable oil. Biodiesel operates in compression ignition engines similar to diesel fuel. It can be burnt in any standard unmodified diesel engine blended with 0% to 100% biodiesel with diesel. Free fatty acid of rice bran oil can be converted into biodiesel fuel as methyl ester by transesterification. Experimental investigations have been carried out using biodiesel as an alternative fuel in single cylinder, compression ignition engine under varying operating conditions. Various parameters such as brake power, specific fuel consumption, exhaust temperature and emissions during combustion process under varying operating conditions with diesel, biodiesel, blends of biodiesel were studied. Various properties of the biodiesel thus developed were evaluated according to ASTM and compared in relation to that of conventional diesel. These tests for biodiesel and diesel oil include density, viscosity, flash point, aniline point/cetane number and calorific value, etc. The prepared biodiesel from free fatty acid of rice bran oil was used for short-term engine performance test with different blends with diesel. It was found that 20 percent blend of biodiesel gave the best performance amongst all blends. There was a net advantage of 3 percent in peak thermal efficiency, substantial reduction in smoke opacity values and 3 to 4 percent increase in NOx. This blend was chosen for long-term test on the CI engine. The engine operating on optimum biodiesel blend showed substantial improved behavior. A series of engine test provide adequate and relevant information that the biodiesel can be used as an alternative, environmental friendly fuel in existing diesel engines without modification in the engine hardware.

Keywords

Biodiesel, Biodiesel Blend, Free Fatty Acid of Rice Bran Oil, Methyl Ester & Emissions.

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A. Chennakesava Reddy ¹, P. Ram Reddy ², B. Kotiveerachari ³

Affiliations
1 Department of Mechanical Engineering, JNTU College of Engineering, Kukatpally, Hyderabad-500072, IN
2 JNT University, Kukatpally, Hyderabad-500072, IN
3 Department of Mechanical Engineering, National Institute of Technology, Warangal-506004, IN

Abstract

It is well known that trajectory planning for robots with many degrees of freedom is a complex task. This paper presents a new method for on-line trajectory planning for robotic arms in dynamic environments. The method presented in this paper avoids local minima by using a two-stage framework. The arms react to dynamic environments using a local and reactive planning method restricted to a subset of its configuration space. Since the subset has few degrees of freedom the computational cost of the on-line stage is very low. An off-line stage chooses the subset of the configuration space that minimizes the probability of blockades and inefficient motions.

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