Standard API A106 GR.B A53 Gr.B tubo in acciaio senza saldatura / Tubo in acciaio ASTM A106 Gr.B A53 Gr.B AP175-79, DIN2I5L , ASTM A106 Gr.B, ASTM A53 Gr.B, ASTM A179/A192/A213/A210 /370 WP91, WP11, WP22. DIN17440, DIN2448, JISG3452-54. Materiale API5L,Gr.Un&B, X42, X46, X52, X56, X60, X65, X70, X80, ASTM A53Gr.A&B,ASTM A106 Gr.A&B, ASTM A135, ASTM A252, ASTM A500, DIN1626, ISO559, ISO3183.1 / 2, KS4602, GB / T911.1 / 2, SY / 5037,