气氛压力对水下高压干法全位置焊缝成形的影响

IMPACT OF ATMOSPHERE PRESSURE ON ALL-POSITION WELD SHAPING OF HYPERBARIC WELDING

研究水下干焊空气环境压力对全位置打底焊接参数及焊缝质量的影响规律。研究表明,环境压力对焊接熔深有一定影响,在环境压力由0.1 MPa增至0.7 MPa时,平焊时的打底焊电流需相应线性递减,上坡焊、仰焊打底电流在0.1～0.3 MPa范围下降较快,之后变化不大,而下坡焊焊接电流在0.1～0.7 MPa范围内呈平缓下降趋势。环境压力对接头力学性能有较大的影响,随着环境压力的增加,焊接接头的抗拉强度、冲击韧度有下降的趋势,而焊缝和热影响区的硬度有上升的趋势。

The influence rule of air environment pressure on all position primary welding parameters and welding quality under hyperbaric environment is investigated. The investigation shows that the environment pressure has some effect on weld penetration. Primary welding current of downhand welding decreases linearly with the ambient pressure increasing from 0,1 MPa to 0,7 MPa; Primary welding current of overhead position welding and upward welding in the inclined position decreases greatly with the ambient pressure increasing from 0.1 MPa to 0,3 MPa and then changes little afterwards. Primary welding current of downward welding in the incline presents lenitive descent trend with the ambient pressure increasing from 0.1 MPa to 0.7 MPa. Ambient pressure has great affection on mechanical property of welding joint, tensile strength and impact toughness of joint decrease with the ambient pressure increasing, while the hardness of HAZ and welding seam increase.