气体绝缘开关设备充气箱激光封焊工艺研究

Study on laser welding technology of gas insulated switchgear

气体绝缘开关设备作为电网中重要部件之一,对其制造的精度和气密性要求极高。目前主要采用手工氩弧焊和人工组装的方式对气体绝缘开关设备充气箱进行焊接,存在焊接变形大、气密性较差等问题,难以保证充气箱的焊接质量。针对上述难点,开发了用于气体绝缘开关设备充气箱激光焊接的自动工装夹具和激光焊接工艺。通过试验验证,开发的自动工装夹具可确保充气箱焊接质量和变形可控;相较于TIG工艺,激光焊接可减小充气箱的焊接变形量,且焊缝质量优异,稳定可靠;采用试验设计法进行工艺优化,激光气密性封焊的最佳工艺参数为激光功率1800 W,焊接速度20 cm/min,保护气为N_(2),保护气流量15 L/min~18 L/min。最后通过氦质谱检漏发现充气箱无漏气情况,密封性良好。

As one of the important components in the power grid,gas-insulated switchgear requires high manufacturing precision and gas tightness.At present,the gas-insulated switchgear filling box is mainly welded by manual argon arc welding and manual assembly,which is difficult to ensure the welding quality of the filling box due to the problems of large welding deformation and poor airtightness.In view of the above difficulties,the automatic tooling fixture and laser welding process for gas-insulated switchgear gas tank laser welding were developed.Through experimental verification,the developed automatic tooling fixture can ensure the welding quality and deformation control of the inflatable box;compared with the TIG process,laser welding can reduce the welding deformation of the inflatable box,and the weld quality is excellent,stable and reliable;using the experimental design method of process optimization,the optimal process parameters of the laser gas-tight sealing welding for laser power of 1800 W,the welding speed of 20 cm/min,shielding gas N_(2),shielding gas flow 15-18 L/min,and finally,no leakage of gas in the inflatable box is found by helium mass spectrometry,and the sealing is good.