perforation coefficient射孔: perforation; gun perforation系数: coefficient; ratio; modulus; ...翻孔系数: burring coefficient锐孔系数: orifice coefficient镜孔系数；流量系数: orifice coefficient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:射孔系数，即可在微信中查询翻译
