... Inner cement line: Portland cement lining as per ISO4179 ductile iron pipeSpecifications: 1) The standard of pipe: ISO 2531 - 1998, EN545 ... NBR rubber, natural rubber, SBR rubber or EPDM rubber tightness ring as per ISO4633 7) DN 80 - 1,200 mm 8 ... ) High strength, lighter than gray iron, good corrosion resistance, no furring, small flow resistance, easy fixing ...