MADEN PARCALARININ SICAK OLARAK OYUL-MASINA MUETEALLIK ISLAHAT

摘要

1280606 Billet piercing CEFILAC (COMPAGNIE DU FILAGE DES METAUX ET DES JOINTS CURTY) 9 Feb 1970 [19 Feb 1969] 6152/70 Heading B3H [Also in Division C1] In a billet piercing process a frusto-conical plug 6 of glass lubricant is placed in the end of a pre-drilled bore 2 of the billet 1 to lubricate the piercing ram 4. The plug is made of glass powder, sodium silicate and water moulded in a closed mould as in Specification 795,989. The plug may have an axial bore of the same size as the billet bore. The billet is heated before piercing.