Green weed and grey barnacles encrust every part under the sea .
水下的部分则覆满了绿色的海藻和灰色的藤壶。
An engine 's heat melts the fine-ground rock , which proceeds to encrust the cooler parts of the mechanism , stopping it from working .
引擎的热量能熔化细岩石颗粒，然后熔岩会就在引擎装置温度较低的部位结成壳，并阻止它继续运行。
But concerns have emerged that salt in the seawater could damage machinery , clog pipes and encrust fuel rods , making it difficult for them to cool .
但有人担心，海水中的盐分会损坏机器、堵塞管道并在燃料棒外层结壳，导致燃料棒很难冷却下来。
This rarely happens , but there are other more practical limits to endurance , including the need to reset instruments and to remove the inevitable weed , barnacles and other marine life that would encrust a glider during very long voyages .
