【判断题】【消耗次数:1】
气环的密封原理除了自身的弹力外,主要还是靠少量高压气体作用在环背产生的背压而起的作用。
正确
错误
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相关题目
【判断题】 气环的密封原理除了自身的弹力外,主要还是靠少量高压气体作用在环背产生的背压而起的作用
①  正确
②  错误
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