The grey cast iron straight pipe produced by centrifugal technology are mainly used in drainpipe through a flexible linkage, which has been past the test of the Hebei Institute of Products Quality intendance and Inspection and the provincial appraisal and has supply the provincial gap. The product has totally get the standards, ISO6954, DIN19522/EN877,GB12772,ASTM-A888, CISPI301,and DS D4307, and has the following advantages: flat and straight, even pipe wall, high strength and density, high smoothness on the inner and outer surface of the wall, no defects in foundry, easy installation, easy maintain, long life ,helpful to environment, fireproofing and no noise.