Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
B28B—SHAPING CLAY OR OTHER CERAMIC COMPOSITIONS; SHAPING SLAG; SHAPING MIXTURES CONTAINING CEMENTITIOUS MATERIAL, e.g. PLASTER
B28B21/00—Methods or machines specially adapted for the production of tubular articles
B28B21/56—Methods or machines specially adapted for the production of tubular articles incorporating reinforcements or inserts
B28B21/60—Methods or machines specially adapted for the production of tubular articles incorporating reinforcements or inserts prestressed reinforcements
B28B21/62—Methods or machines specially adapted for the production of tubular articles incorporating reinforcements or inserts prestressed reinforcements circumferential laterally tensioned