Blast furnace hot-blast stove flue flange connecting part burst treatment method

Abstract

The invention relates to a blast furnace hot blast stove flue flange connecting part burst treatment method. The method comprises the following processing steps: 1, deeply analyzing the reason of frequent explosion welding of the flue valve flange of the blast furnace hot blast stove, performing double-sided welding on the joint of the flange and a flue pipe in design and construction in order toinsulate a flue steel shell and a weld joint, and then spraying a spray coating with the thickness of about 100mm on the joint of the flange and the flue pipe; step 2, performing beveling type deep welding on the original butt joint surface of the flange and the flue pipe by utilizing the opportunity that the blast furnace stops working in a short term and the hot blast stove stops working; 3, carrying out annular steel plate baling on the flange and the flue pipe, improving the strength of the joint of the flange and the flue pipe, and welding two slurry jacking holes; and 4, filling the flange bale with a heat insulation mass pressure slurry, performing reverse heat insulation from the outer portion of the original pipe shell, stabilizing the original weld joint temperature and materialstrength, and thus reducing bursting, caused by large temperature difference and strength reduction, of weld joint materials under the action of high pressure.

Description

technical field [0001] The invention belongs to the technical field of blast furnace hot blast stove equipment, and relates to a method for treating bursting of a flange connection part of a blast furnace hot blast stove flue. Background technique [0002] The pressure in front of the flange of the flue valve of the hot blast stove varies depending on the air supply pressure of the blast furnace, and usually can reach 0.3-0.4Mpa. The flue gas temperature in front of the flue valve flange is about 300-400°C. If the pipe from the flue pipe to the flange is vertically reduced in diameter, the sprayed coating on the flange of the flue valve flange will easily fall off under the temperature difference of 200°C and the alternating micro-pressure and high-pressure, resulting in the temperature difference between the flange and the flue pipe welding place. If it is too large, the strength of the original weld material will decrease, which will eventually lead to frequent explosion ...

AI Technical Summary

Problems solved by technology

[0003] In order to overcome the above-mentioned shortcomings of the prior art, the present invention provides a blast furnace hot blast stove flue flange connection part burst treatment method, which fully utilizes the heat insulation effect of refractory materials, can effectively stabilize the surface temperature of the steel shell, and prevents the welding gap from being caused by large temperature differences. , the weakening of the strength leads to the characteristics of bursting. In the case where double-sided welding cannot be performed inside the pipe and the refractory material is repaired, on the basis of welding the original interface externally, the original pipe shell is used as the bottom plate filled with heat insulation material, and pressed into the insulation After thermally pressing the slurry, the temperature of the original weld is stabilized from the outside of the original tube shell, and then the strength of the connection between the flange and the flue pipe is improved by welding with a packed steel plate, and the flange burst is thoroughly treated at one time, reducing the operation and point of the hot blast furnace. Reduce the labor load and maintenance cost of inspection and maintenance personnel, and eliminate potential safety hazards

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