symmetrical administration对称: symmetry; symmetrical管制: control非对称管制: asymmetrical administration; asymmetrical control对称管伸缩: symmetric stretch标称管壁厚: nominal wall thickness下载手机词典可随时随地查词查翻译关注微信公众号:chachacidian,回复:对称管制,即可在微信中查询翻译