Permanency versus evolution--The route of the development of mandrel mill technology--commemorating the 120th anniversary of the invention of the rotary piercing process by Mannessmann brothers是什么意思_Permanency versus evolution--The route of the development of mandrel mill technology--commemorating the 120th anniversary of the invention of the rotary piercing process by Mannessmann brothers在线翻译_英语_读音_用法_例句