HL-2A装置真空室内部件数目繁多，容器本体上的密封部位多达几百个，特别是真空室内多极场线圈真空套从真空室的预装阶段开始，经常会出......

There are many inner items in vacuum vessel, and hundreds of seals on the vessel borts in the HL-2A tokamak, so it is di......