何为billet piercing(气瓶制造)? The present invention relates to a method of producing a cylindrical shell used for fabricating a gas cylinder to contain a gas. More particularly, the present invention relates to such a method in which a billet of circular, transverse cross-section is used to form the cylindrical shell by billet piercing . Even more particularly, the present invention relates to such a method in which the billet is formed of a first section of steel and a second section of liner material so that the cylindrical shell has an outer cylindrical form made of steel and an inner liner insert formed of the liner insert material. 求助各位。谢谢。查看更多1个回答 . 3人已关注