A SYMPOSIUM FOR APPRAISING THE OUTSIDE SPIRAL PIPES AND THEIR PRODUCTION PROCESS HELD AT TIANJING SEAMLESS STEEL PIPE FACTORY是什么意思_A SYMPOSIUM FOR APPRAISING THE OUTSIDE SPIRAL PIPES AND THEIR PRODUCTION PROCESS HELD AT TIANJING SEAMLESS STEEL PIPE FACTORY在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句