低气压对自保护药芯焊丝焊缝成形的影响

对低气压地区自保护药芯焊丝电弧焊接的焊缝成形及其影响因素进行了研究.结果表明,在相同焊接工艺参数设定下,气压愈低,焊缝的熔深愈浅、熔宽愈宽、余高愈小;气压降低导致电弧的冷却作用减弱,弧柱区的直径与正常气压相比将增大,电弧的稳定性和挺度下降.电弧行为的改变影响了焊缝成形质量,气压越低,焊缝成形的对称性越差;焊炬高度的增加对焊缝成形及电弧稳定性同样有不利影响,适当增加送丝速度和降低电弧电压有助于焊缝成形质量的改善.研究结果为低气压地区的自保护药芯焊丝焊接工艺参数制定和优化提供了科学依据.

Effect of low atmospheric pressure on weld formation of arc welding with self-shielded flux-cored wire

The weld formation and its influence factors of arc welding with shelf-shielded flux-cored wire in low atmospheric pressure areas were studied. The research results show that at the same welding parameters, the lower atmospheric pressure is,the more shallow the weld penetration depth is, the wider the weld width is,and the lower the weld reinforcement is. Due to weakened cooling effect to the arc by low atmospheric pressure, arc diameter increases compared with the normal pressure, arc stability and stiffness decrease. The change of the arc behavior influences the weld formation. The symmetry of weld formation becomes poor. The increase of welding torch height has negative influence on weld formation and arc stability as well. The increase of wire feeding rate and decrease of arc voltage in a certain range can be good for improving the weld quality. The research results provide scientific basis for formulating welding process specifications and parameters optimization of arc welding with self-shielded flux-cored wire in low atmospheric pressure areas.