Cross sector seamless line, namely rail bar, rail bar and rail switch direct welding; the vertical force and displacement are direct transmitted between rail bars.

跨区间无缝线路，即轨条与轨条、轨条与道岔直接焊接，轨条之间直接传递纵向力和位移。

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Lederman and his team of engineers spent 25 years dissolving and welding plastic until they had a totally seamless, continuous surface that minimizes the threat of clots.

FORBES: Lonely Heart