Analysis of Arc-weld Pool Behavior of Double-Frequency Modulated Pulse TIG Root Pass Welding

doi:10.3901/JME.2023.12.245

Abstract

Abstract: An improved double frequency modulated pulse TIG process was applied to deeply weld the root pass metal with low angle and large root face for increasing the production efficiency and weld bead quality as well as meeting the new requirements of one-sided welding with double-sided formation in nuclear vessel made with medium-tick plates. The experimental control system was established, and multi-repeatable experiments were conducted with low frequency and double frequency modulated pulse current, respectively. A reliable one-sided welding with double-sided formation was successfully achieved with 60 degree and 5 mm thick root face. The increased mechanism of the weld penetration was also explained by analyzing the arc and weld pool behavior combined with the temperature filed evolution of the weld pool surface. The results indicated that the modulated pulse arc has a higher energy density and pierced force, easily piercing the liquid weld metal film and forming the keyhole. The variation of energy in the weld pool changes lower, and the thermal inertia of the weld pool is enhanced. The solidification velocity is also effectively decreased, the weld penetration, thus, is increased. Therefore, the added high frequency pulse current provides a good dynamic thermal-force balance for achieving a sound one-sided welding with double-sided formation.

Key words: pulse TIG, arc shape, weld pool, one-sided welding with double-sided formation, root pass welding

CLC Number:

TG444

ZHANG Gang, XU Zilong, SHI Yu, ZHU Ming, FAN Ding. Analysis of Arc-weld Pool Behavior of Double-Frequency Modulated Pulse TIG Root Pass Welding[J]. Journal of Mechanical Engineering, 2023, 59(12): 245-252.

References

[1] CUI S L,LIU Z M,FANG Y X,et al. Keyhole process in K-TIG welding on 4mm thick 304 stainless steel[J]. Journal of Materials Processing Technology,2017,243:217-228.
[2] 齐铂金,杨舟,杨明轩,等. 超高频脉冲GTAW工艺特性分析[J]. 机械工程学报,2016,52(2):26-32. QI Bojin,YANG Zhou,YANG Mingxuan,et al. Analysis on characteristic of ultra high frequency pulsed gas tungsten arc welding process[J]. Journal of Mechanical Engineering,2016,52(2):26-32.
[3] YANG M X,ZHENG H,LI L,et al. Arc shape characteristics with ultra-high-frequency pulsed arc welding[J]. Applied Sciences,2017,7(1):45-51.
[4] 孙福成,王伟波,张志强,等. 窄间隙热丝TIG焊在反应堆压力容器上的应用及质量控制研究[J]. 电焊机,2019,49(4):54-58. SUN Fucheng,WANG Weibo,ZHANG Zhiqiang,et al. Application and quality control of narrow gap hot wire TIG welding technology for reactor pressure vessel[J]. Electric Welding Machine,2019,49(4):54-58.
[5] OPDERBECKE T,GUIHEUX S. TOPTIG:Robotic TIG welding with integrated wire feeder[J]. Welding International,2009,23(7):523-529.
[6] TATHGIR R,BATISH. A-TIG welding process for enhanced-penetration in duplex stainless-steel:Effect of activated fluxes[J]. Materials and Manufacturing Processes,2019,34(15):1659-1670.
[7] VIDYARTHY R S,DWIVEDI D K. Activating flux tungsten inert gas welding for enhanced weld penetration[J]. Journal of Manufacturing Processes,2016,22:211-228.
[8] MATTHEWS J R,PORTER J F,CHURCH J,et al. An evaluation of T. I. M. E. welding of HY80 plate[J]. Welding Journal,1991,70(2):35-41.
[9] 樊丁,郑发磊,肖磊,等. 高效MAG焊接熔滴过渡行为及交变磁场控制试验分析[J]. 焊接学报,2019,40(5):1-5. FAN Ding,ZHENG Falei,XIAO Lei,et al. Droplet transfer behavior and alternating magnetic field controlled experimental study of high efficiency MAG welding[J]. Transaction of the China Welding Institution,2019,40(5):1-5.
[10] WU K,XIE P,ZHAN J,et al. Analysis of current phase influence on weld seam formation in double-wire DP-GMAW[J]. The International Journal of Advanced Manufacturing Technology,2019,103(9-12):4825-4835.
[11] 李俐群,郝雨,彭进. 表面张力对激光深熔焊熔池流动的影响[J]. 焊接学报,2019,40(2):13-19. LI Liqun,HAO Yu,PENG Jin. Effect of surface tension on flow in laser deep penetration welding molten pool[J]. Transaction of the China Welding Institution,2019,40(2):13-19.
[12] 汪为庆. 核电站控制棒导向筒组件半方管电子束焊缝熔深问题分析及改进运用[J]. 电焊机,2020,50(11):104-108. WANG Weiqing. Analysis and improvement application of welding depth of electron beam in half square tube of guide tube assembly of control rod in nuclear power plant[J]. Electric Welding Machine,2020,50(11):104-108.
[13] 李天庆,陈璐,张宇,等. 气流再压缩等离子弧焊接电弧行为[J]. 焊接学报,2020,41(5):50-55. LI Tianqing,CHEN Lu,ZHANG Yu,et al. Arc behavior of plasma arc welding with gas flow recompression[J]. Transaction of the China Welding Institution,2020,41(5):50-55.
[14] 刘光云,吕向阳,王义. STT焊接工艺参数对根焊质量的影响[J]. 焊接技术,2010,39(5):56-58. LIU Guangyun,LÜ Xiangyang,WANG Yi. Effect of welding parameters on root pass welding quality of STT[J]. Welding Technology,2010,39(5):56-58.
[15] 陈姬,武传松,Pittner A,等. ForceArc双面焊熔池流场与温度场的数值模拟[J]. 焊接学报,2015,36(7):9-12. CHEN Ji,WU Chuansong,PITTNER A,et al. Numerical simulation of flow field and temperature field in Force Arc double-sided weld pool[J]. Transaction of the China Welding Institution,2015,36(7):9-12.
[16] 杨明轩,齐铂金,从保强,等. 不锈钢超高频直流脉冲GTAW焊缝成形行为[J]. 焊接学报,2012,33(11):31-34. YANG Mingxuan,QI Bojin,CONG Baoqiang,et al. Weld appearance behavior in welding pool of stainless steel by ultrahigh frequency pulse GTAW process[J]. Transaction of the China Welding Institution,2012,33(11):31-34.
[17] 杨明轩,杨舟,从保强,等. 超高频脉冲电弧焊接熔池金属流动行为[J]. 北京航空航天大学学报,2015,41(4):589-593. YANG Mingxuan,YANG Zhou,CONG Baoqiang,et al. Metal molten behavior with ultra-high frequency pulsed arc welding[J]. Journal of Beijing University of Aeronautics and Astronautics,2015,41(4):589-593.
[18] 从保强,王义朋,齐铂金,等. 铝合金超音频双脉冲调制VPTIG深熔焊接技术[J]. 航空制造技术,2018,61(8):38-42. CONG Baoqiang,WANG Yipeng,QI Bojin,et al. Ultrasonic double pulsed deep penetration VPTIG welding for aluminum alloys[J]. Aeronautical Manufacturing Technology,2018,61(8):38-42.
[19] Beer D. Guidebook for the design of ASME section IX pressure vessels[M]. NewYork:ASME Press,2018.
[20] ZHU Z W,ZHANG G,WANG K F,et al. Joint penetration monitoring in low-frequency pulsed GTA root pass welding of medium-thick steel plates[J]. Welding Journal,2021,100(9):281-290.
[21] 邹江林,王利达,祝宝琦,等. 光纤激光-TIG电弧复合焊接等离子体形态的可视化观察[J]. 中国激光,2019,46(12):110-116. ZOU Jianglin,WANG Lida,ZHU Baoqi,et al. Visual observation of plasma morphology during fiber laser-TIG arc-hybrid welding[J]. Chinese Journal of Lasers,2019,46(12):110-116.