PULVERIZED COAL INJECTION LANCE

摘要

PURPOSE: A pulverized coal injection lance is provided which is not bended by dead load even at a high temperature by forming expansion transformation members on upper and lower parts of the outer circumferential surface of an inner tube of the pulverized coal injection lance consisting of a dual pipe. CONSTITUTION: In a pulverized coal injection lance which is consisting of a dual pipe of an outer tube and an inner tube in a hollow blow pipe positioned at tuyere inside a blast furnace to inject pulverized coal into the blast furnace, the pulverized coal injection lance comprises a first expansion transformation member(14) which is mounted on the upper part of the outer circumferential surface(12) of the inner tube(10) arranged in the blow pipe and has a low thermal expansion coefficient compared to the inner tube(10); and a second expansion transformation member(16) which is mounted on the lower part of the outer circumferential surface(12) of the inner tube(10) arranged in the blow pipe and has a high thermal expansion coefficient compared to the inner tube(10), wherein the pulverized coal injection lance is not bended by dead load in a high temperature atmosphere by using difference of thermal expansion coefficient between the first and second expansion transformation member(14,16) and the inner tube(10).