设计的，现在胶皮部分有些老化，弹性差了，铁环和胶片之间密封就差了，推铁环就是让密封的紧一些

来源: LWL 于 2020-05-09 09:32:24 [旧帖] [给我悄悄话] 本文已被阅读：次

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