Malleable iron pipe ﬁttings are malleable cast iron commonly known as Magnesium Steel, cast into white cast iron pieces, and then forgeable and annealed. The graphite in malleable cast iron is a ﬂocculent, which has little eﬀect on the separation of the matrix. Therefore, its mechanical properties are higher than that of gray cast iron, its ductility and toughness are good, but malleable cast iron cannot be forged. The malleable cast iron has diﬀerent matrix structure and its properties. It is not the same, of which the black heart malleable cast iron has high plasticity and toughness, and the pearlite malleable cast iron has high strength, hardness and wear resistance. Malleable iron pipe ﬁttings are suitable for petroleum, chemical, power, construction, water treatment and other ﬁelds.
What is the diﬀerence between American standard ﬁttings and national standard ﬁttings?