Please use this identifier to cite or link to this item: http://hdl.handle.net/1959.3/220594

Title

The influence of power source characteristics on particulate fume generation and composition

Author(s)

French, I. E.;  Tyagi, V. K.;  Brooks, Geoffrey

Abstract

Particulate fume generation rates and fume composition have been measured for a range of continuous wire arc welding consumables as a function of power supply type. Welding wires considered included gas-shielded cored wires of the rutile-flux, basic-flux and metal core types, for joining structural steels; gas-shielded solid and flux-cored wires for stainless steel; and an open-arc surfacing wire. The range of power supply types used included conventional (transformer-rectifier) DC units, conventional (transistor switched) pulsed supplies as well as both low frequency and high frequency inverter-based power supplies. The inverter type power supplies were used in both the DC and pulsed modes. In all cases fume measurements were made at average welding currents at the low and high ends of the normal operating ranges. Significant decreases in fume formation rate, compared to that from conventional DC power supplies, were found for several combinations of power source and consumable type. The magnitude of these reductions depended on the particular power source/wire combination. For the cored joining wires for structural steels the reductions in fume formation rates were generally in the range 20 to 50% with the most consistent reductions occurring with the conventional-pulsed and pulsed high frequency inverter supplies. Both the solid and cored wires for stainless steel also showed considerable reductions in fume generation rate with certain power supplies. Reductions of about 60% compared to those from conventional DC power supplies were found from both stainless steel wire types with the most consistent reductions occurring with the conventional-pulsed power supply. Fume generation rates from the open-arc surfacing wire were found to be reduced by 30 to 50% in some instances and again the most consistent reduction was with the conventional-pulsed supply. Chemical analyses of the collected fume indicated that in most instances power source type did not have a major influence on the chemical composition. This was certainly the case for the flux-cored wires for structural steel. However the results for the stainless steel and hardfacing wires suggested that the lowest hexavalent chromium (Cr(VI)) levels were achieved with the conventional DC power source.

Publication type

Conference paper

Source

Selected papers from 'Productivity beyond 2000', the IIW Asian Pacific Welding Congress 1996, incorporating the 58th NZIW Annual Conference and the WTIA 43rd National Welding Congress, Auckland, New Zealand, 04-09 February 1996, Vol. 2, pp. 591-610

Publication year

1996

Keyword(s)

Flux-cored arc welding;  Gas metal arc welding;  GMAW;  Hardfacing;  Inverters;  Power supply;  Pulsed welding;  Welding fume

Publisher

Abington Publishing

ISBN

9781855733169, 1855733161

Publisher URL

http://www.woodheadpublishing.com/en/

Copyright

Copyright © 1996, The New Zealand Welding Committee.

Peer reviewed