The gray cast iron straight pipe produced by centrifugal technology aremainly used in drainpipe through a flexible linkage, which has been past thetest of the Hebei Institute of  Products QualityIntendance and Inspection and the provincial appraisal and has supply theprovincial gap. The product has totally get the standards: ISO6594, DIN19522/EN877,GB12772, ASTMA888, CISPI301, and KSD4307, and has the following advantages: flatand straight, even pipe wall, high strength and density, high smoothness on theinner and outer surface of the wall, no defects in foundry, easy maintain, longlife, helpful to environment, fireproofing and no noise.