Maintenance is one of the duties that almost every underwater photographer wishes they didn't have to do.
水下相机的日常维护保养是所有水下摄影师都不太愿意去做的事情。
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The job of maintenance adopts the underwater diamond wire saw for cutting the oil - gas pipelines aiming at the characteristic of the benthal condition and the structure of the pipelines.
The investigations show that the secondary maintenance for steel pipe piles by the methods of underwater coating and drainage covering ia an effective measures.