NF E29-018:1986 Industrial pipework. Bracing rings for flanges with female (groove or spigot), or male (tongue or spigot) faces. ISO PN 2,5 to ISO PN 50.
1986NF E29-018:1986 Industrial pipework. Bracing rings for flanges with female (groove or spigot), or male (tongue or spigot) faces. ISO PN 2,5 to ISO PN 50.