drop.3, stepped transition port eliminates the cavity, where material will accumulate.4, short length of face to face, reduced raw material cost and installation space, strengthened the pipeline strength.5, scientific design for sealing packing box, makes the sealing more safe and wear well.Materials of construction1, size range: 2''-64'' (DN50mm-DN1600mm)2, pressure grade be 1.0Mpa & 1.6 M pa.3, body construction and material : one-piece body with wafer or flange connection end, cast iron & st