Analysis on Defects of Alloy Steel Pipe Centrifugally Casted;

With the development of Sinopec and the increasing proportion of the Sulfur in petroleum, the demand of the alloy steel pipe used in Sinopec producing equipments is unceasingly increasing.

Through testing and analysing of 12Cr1MoV low alloy steel tube,it is showed that the structure of weld and heat-affected zone is bainite and ferrite;the grain is fine and the microhardness is higher in weld and fine grained zone;the grain is coarse zone;the structure of mother metal is ferrite and pearlite and its microhardness is further lower.