Rugged: Virtually indestructible and practically maintenance free.

坚固：几乎无法毁坏，不需维修。

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The flywheel energy storage unit, which replaces the conventional chemical battery, is maintenance free, has long life and emits no pollution.

飞轮储能单元代替传统的化学电池，具有免维护、寿命长、无污染的特点。

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In view of the defects of steam soot-blowers, WS-10 type maintenance free sonic soot-blowers are used to replace the original steam ones in the Power Plant of Guangzhou Petrochemical General Works.

由于蒸汽吹灰器存在较多缺点，广州石油化工总厂动力厂采用了WS-10型声波吹灰器取代原来的蒸汽吹灰器，实现了免维护。

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With a top speed of 14 mph it was anything but fast, but it was virtually maintenance free.

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Highly effective, and completely maintenance free, it kept their pueblos warm in winter, and cool in the summer using only stone age technology.

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His maintenance-free bike uses a "secret" mix of organic materials to make it waterproof and fireproof, and is then lacquered to give it a friendlier appearance.

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