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
Arora, Navneet
- Influence of Flux Basicity on Weld Bead Geometry and HAZ in Submerged Arc Welding
Authors
1 Welding Research Laboratory, University of Roorkee, U.P., IN
2 Punjab Engineering College, Chandigarh, IN
Source
Indian Welding Journal, Vol 23, No 3 (1991), Pagination: 127-133Abstract
Weld bead geometry and heat affected zone which are generally dependent on the welding parameters may also be influenced by the chemical composition of flux i.e. the flux base and its basicity in submerged arc welding. The different flux constituents which impart different physical/chemical properties to the flux may also affect the weld bead geometry and heat affected zone.
Investigation have been carried out to study the combined effect of welding parameters and flux basicity which is one of the measure for chemical nature of the flux on weld bead geometry and heat affected zone in the case of mild steel.
It has been found that the welding parameters and flux basicity appreciably influence the depth of penetration and the weld bead width. The reinforcement is also influenced by the welding parameters, however, flux basicity does not seem to affect reinforcement appreciably.
The widths of heat affected zones at the centre line of the weld bead and at the toe of the weld are appreciably influenced by the welding parameters. Higher basicity fluxes generally give rise to lower width of heat affected zones as compared to low basicity fluxes.
- Enhancement in Mechanical Properties of Tailored Welded Blanks Due to Pulsed Tig Welding
Authors
1 Bharat Heavy Electrical Limited, Haridwar, IN
2 Institute of Petroleum Technology, Gandhinagar, IN
3 Department of Mechanical and Industrial Engineering, Indian Institute of technology Roorkee, Roorkee, 247 667, IN
Source
Indian Welding Journal, Vol 42, No 4 (2009), Pagination: 38-45Abstract
The present paper reports experimental results on enhancement in mechanical properties of tailored welded blanks due to Pulsed TIG welding. Experimental evaluation of various mechanical properties has been made under the influence of varying peak current, pulse frequency and pulse width. The resulting welds have been checked for ultimate tensile strength, % elongation, hardness, toughness and fatigue life. The mechanical properties of Pulsed TIG welded tailored blanks have further been compared with that produced by conventional TIG welding. It has been observed that the Pulsed TIG welding can successfully be employed to improve the mechanical properties of tailored welded blanks. The results of experiments have been analyzed and related discussion has been presented.
Keywords
Pulsed TIG Welding, Mechanical Properties, Tailored Welded Blanks.- Impact of Process Modelling on Current Direction of Welding Research and Future Targets
Authors
1 Institute of Petroleum Technology, Gandhinagar - 382 007, IN
2 Indian Institute of Technology Roorkee, Roorkee - 247 667, IN
Source
Indian Welding Journal, Vol 41, No 4 (2008), Pagination: 43-50Abstract
The present paper gives a description of process modelling and its impact on current direction of welding research and future targets. It analyses the research work carried out in the filed of process modelling and presents quantitative analysis. The present work classifies and subsequently quantifies the welding research on the basis of approaches including modelling and simulation, product development, cause-effect analysis and sensor and control. The analysis indicates that modelling based research is primarily reported for existing technologies and existing materials. Research in new technologies using modelling is still is in developing stages and new materials based research is primarily carried out with cause-effect based analysis. The paper also mentions the future targets in welding research and indicates the role of process modelling in achieving the targets.
Keywords
Process Modelling, Welding Research, Future Targets.- Modified Mathematical Models for Melting Rate in Submerged Arc Welding
Authors
1 Institute of Petroleum Technology, Gandhinagar, IN
2 Department of Mechanical and Industrial Engineering, Indian Institute of Technology, Roorkee, IN
3 Department of Mechanical and Industrial Engineering, IN
Source
Indian Welding Journal, Vol 40, No 4 (2007), Pagination: 21-32Abstract
Modified mathematical models for melting rate during submerged arc welding with straight and reverse polarities have been proposed. The present work is a result of a critical analysis of existing models and subsequent modification in order to improve the predictability and practicability. The proposed models bridge the gap between less scientific shop-fioor-friendly models and scientifically correct but not so shop-floor- friendly models. Instead of experimental measurement of electrode extension or making the assumption that the electrode extension is equal to contact tube to work-piece distance, the present work models the role of electrode extension during melting by considering the effect of process parameters on it. On the other hand, influence of process parameters on arc heating has also been incorporated. The developed models cover the effect of fundamental parameters like current, voltage, electrode extension and wire diameters.
Simulated annealing has been used to calibrate the proposed models and subsequently the models are validated with data points different from the points used for model calibration. The modified models provide better accuracy than the models that have been constituted with the above stated assumption as well as it is more practical than those models in which actual electrode extension has been experimentally measured. The outcome of investigation has been analyzed in terms of improvement in the predictability, resemblance with physics of the process and generalization capacity of the models. The approach of the present work is applicable for future research in other welding processes.