This content is not included in your SAE MOBILUS subscription, or you are not logged in.
EFFECT OF FIT-UP CONDITIONS WHEN USING CONSTANT CURRENT CONTROL SYSTEMS FOR RESISTANCE SPOT WELDING
ISSN: 0148-7191, e-ISSN: 2688-3627
Published March 01, 1993 by SAE International in United States
Annotation ability available
Resistance welding control systems utilizing secondary current feedback receive widespread utilization both in Europe and Japan. However, these types of control systems are only beginning to be used in any extended basis in this country. Currently, two variants of these systems are available; so called “self-teaching” systems, and “learning curve” systems. Either system has been shown to be capable of providing a stable secondary resistance welding current within two cycles. Recent work has indicated, however, that the self-teaching type control systems may be adversely affected by non-optimum set-up conditions, particularly poor fit-up and the introduction of organics (sealers or adhesives) at the faying surface. This work examines the performance of learning curve type constant current control systems under these adverse set-up conditions. Six conditions were selected for study; three degrees of progressively poorer fit-up, with and without an organic sealer. For each condition, current range curves were generated, and process measurements taken. For all sets of conditions, the learning curve control system performed well. Current range results indicated no premature expulsions associated with controller function, and in fact current range curves for all conditions were quite similar. Process results indicated that in all cases the current waveforms were quite stable. Current, voltage and dynamic resistance waveforms were quite similar for all trials. For the trials without adhesive, the firing angle results indicate that the controller functioned by compensating for variations in dynamic resistance throughout the process. A similar relationship between firing angle and dynamic resistance was not noted for the welds made with sealer.
CitationGould, J., Kimchi, M., and Mitchell, T., "EFFECT OF FIT-UP CONDITIONS WHEN USING CONSTANT CURRENT CONTROL SYSTEMS FOR RESISTANCE SPOT WELDING," SAE Technical Paper 930451, 1993, https://doi.org/10.4271/930451.
- Androvich, D. A. 1992 Resistance welding constant current heat control Sheet Metal Welding Conference V AWS Detroit Section Detroit, Michigan
- Ferguson, H. S. 1986 Programmed constant-total weld pulse current control Sheet Metal Welding Conference II AWS Detroit Section Detroit, Michigan
- Dickinson, D. W. Franklin, J. E. Stanya, A. 1980 Characterization of spot weld behavior by electrical parameter monitoring Welding Journal Research Supplement 59 6 170s 176s
- Gould, J. E. Peterson, W. A. 1988 Resistance welding research evaluations of coated steels: part two, dynamic resistance studies EWI Research Report MR8809 Edison Welding Institute Columbus, OH
- 1974 Welding acceptance test for galvanized steel Ford Laboratory and Chemical Engineering Test Methods Detroit, Michigan
- Rivett, R. M. Hurley, J. P. 1990 Weld bonding of zinc coated sheet steels Sheet Metal Welding Conference IV AWS Detroit Section Detroit, Michigan
- Gould, J. E. Peterson, W. A. 1988 Resistance welding research evaluations of coated steels: part three, nugget development studies EWI Research Report MR8814 Edison Welding Institute Columbus, OH
- Gould, J. E. Campbell, D. H. 1988 The effect of conducting primers on the resistance spot weldability of automotive type sheet steels Sheet Metal Welding Conference III AWS Detroit Section Detroit, Michigan
- Higdon, A. Ohlsen, E. H. Stiles, E. B. Weese, J. A. 1967 Mechanics of Materials, Second Ed. John Wiley and Sons New York
- Savage, W. F. Nippes, E. F. Wassel, F. A. 1977 Static contact resistance of series spot welds Welding Journal Research Supplement 56 11 365s 370s