From the composition of pipe system, cast iron drainage pipe can be divided into three categories: straight pipe, pipe fittings and auxiliary parts. Direct pipe is the main component of the pipe system; various kinds of pipe fittings are the guarantee of the drainage system function (collecting, turning, ventilation, closing water, elimination can slow pressure, check and clear obstacles, etc.); auxiliary parts mainly connect and seal function. The A-type pipe has the advantages of high interface strength, good sealing performance and strong seismic performance.
