Method for eliminating carbon deposition in roller-bottom continuous nodulizing annealing furnace

Abstract

The invention discloses a method for eliminating carbon deposition in a roller-bottom continuous nodulizing annealing furnace. The method comprises the following steps: closing an RX gas intake valve of the annealing furnace and furnace doors in the two sides in a no-load state of the annealing furnace; then heating the annealing furnace, controlling a temperature in a hearth to achieve 650+/-10 DEG C and keeping constant temperature, and detecting tail gas of the annealing furnace; stopping heating when the content value of CO2 in the tail gas is not changed any more, and opening the furnace doors in the two sides; closing the furnace doors in the two sides again after air enters the annealing furnace and the hearth is fully filled with air, and repeating the heating treatment process; and stopping operation when the content value of CO2 in the tail gas is lowered to 0.3%-0.5%, and then completing elimination for the carbon deposition in the annealing furnace. The elimination method is capable of efficiently and thoroughly eliminating the carbon deposition in the roller-bottom continuous nodulizing annealing furnace, so that the annealing furnace recovers to an initial use effect; and moreover, the elimination method is short in elimination operation period, low in elimination and maintenance cost, and capable of effectively preventing recarburization in the case of ensuring no decarburization of an annealing material through regular implementation, thereby ensuring the annealing quality of refined wire products, reducing pollution to environment, and increasing the production efficiency.

Description

Technical field [0001] The invention relates to the technical field of removing carbon deposits in a continuous annealing furnace, in particular to a method for removing carbon deposits in a roller hearth type continuous spheroidizing annealing furnace. Background technique [0002] The spheroidizing annealing of bearing forging billet steel and alloy tool steel is an extremely important heat treatment process. The carbides of spherical pearlite should be uniformly, finely, dispersed, and roundly distributed. The surface of the annealed parts should be free of oxidation and depleted carbon to ensure implementation Cold rolling, cold drawing, cold extrusion, cold rolling and expansion and other high-quality materials, so high-quality spheroidizing annealing is a key process for stable control and ensuring ideal microstructure, creating conditions for subsequent heat treatment to ensure quenching of parts When obtaining the ideal structure of cryptocrystalline and fine crystalline ...

AI Technical Summary

Problems solved by technology

[0003] The roller hearth continuous spheroidizing annealing furnace meets the requirements of the rapid isothermal spheroidizing annealing process in terms of furnace body design. The spheroidizing annealing time is short, the annealing quality is good, and the energy consumption is low. Working in a gas environment for a long time, carbon powder (carbon crystallization) will inevitably be produced on the inner wall and pipes. If it accumulates to a certain extent, it will affect the composition of the RX gas protective atmosphere, cause carbonation of the annealed material, and cause a significant reduction in the quality of the steel after spheroidizing annealing and safety. Hidden danger

[0004] In order to deal with the carbon deposition problem of the annealing furnace, the method of replacing the furnace lining and cleaning the pipes is usually used at present. A professional processing team is required to dismantle the furnace lining and clean the pipes. The construction period generally takes 7 to 15 days, and the construction is highly specialized and the cycle time long, high maintenance costs, and the solid waste generated after cleaning is likely to cause environmental pollution

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