连续性给油,用针阀式油杯、油绳式油杯、油环式等只能小量连续供油,采用油泵、浸入油池等方式,可大量供油,不仅保证了润滑,而且还能靠油带走热量,实现降温。
A campus emergency ______ occur at any time of the day or night, weekend, or holiday, with little or no warning.
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