Tuesday, September 13, 2022
问题:接触高浓度刺激性气体可引起喉头水肿或痉挛,表现为(),(),()...
Friday, September 16, 2022
Sunday, September 11, 2022
问题:登高作业时为了便于安装,脚手板宽度不得大于0.6米。...
Sunday, September 11, 2022
Tuesday, September 13, 2022
问题:焊接电流增加时,导致电弧潜入熔池,使电弧摆动范围缩小,促使熔宽()...
Thursday, October 5, 2023
问题:小孔型等离子弧焊也可以采用脉冲电流焊接,脉冲频率可以是()Hz。A、10B、15C、20...
Saturday, March 25, 2023
Friday, April 11, 2025
Saturday, September 17, 2022
问题:MIG焊适用于铝及铝合金、不锈钢等材料中、厚板焊接。...
Friday, September 16, 2022
问题:从业人员只要了解其作业场所和工作岗位上的安全生产规章制度和操作规...
Tuesday, September 13, 2022
问题:高真空电子束焊的加速电压为40kV~150kV。...
Saturday, October 19, 2024
问题:浸沾钎焊的优点是(),液态介质保护焊件不氧化。A、加热速度快B、生产效率高C、保温性好...
Sunday, February 5, 2023
Friday, September 16, 2022
Thursday, September 15, 2022
问题:建设项目的安全设施应当与主体工程同时设计、同时施工、同时投入生产...
Tuesday, September 13, 2022
Friday, September 16, 2022
问题:弧柱中所进行的电过程较复杂,而且它的温度不受材料沸点的限制,因此...
Tuesday, September 13, 2022
Friday, September 16, 2022
问题:体外心脏挤压法为提高效果,应增加挤压频率,最好能达到每分钟()次...
Tuesday, September 13, 2022