mainsn.总线；主要管道名词main的复数形式.mains fluctuations电源波动mains power supply电力网供电,系统供电Mainstee evaporator梅因斯提蒸发器mains power failure电源电力故障mainshaft snap ring主轴开口环mains connection set电源设备mainshaft oil baffle主轴挡油圈mainshaft thrust cap主轴推压盖mainspring cock jewel条上钻mains voltage heating干线电压加热