When these lines expand within the outer pipe, they often move and flex in a process  called thermal mechanical bending or TMB.

当这些管线在外管内膨胀时，它们通常会在称为热机械弯曲或 TMB 的过程中移动和弯曲。

Over hundreds or thousands of cycles of TMB, the paper insulation around each conductor  can begin to soften or tear, eventually leading to a dielectric breakdown (in other words, arcs and short circuits).

经过数百或数千次 TMB 循环，每个导体周围的纸绝缘体可能会开始软化或撕裂，最终导致介电击穿（换句话说，电弧和短路）。