【单选题】关于球墨铸铁管推入式和机械式安装的特点说法错误的是()
A.
推入式接口具有可靠的严密性、良好的抗震性和耐腐蚀性
C.
机械式接口安装时不需要安装机具,推入式接口安装时需要
D.
机械式接口不需要橡胶圈,推入式接口需要橡胶圈
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