The Simulation And Optimization Of The Anneal Technique Of The Full-hydrogen Bell-type Annealer Furnace

The full-hydrogen annealer furnace is a widely used industrial furnace for steel stripannealing after cold rolling. Since the first rolled scroll bell furnace was introduced andmanufactured in the1950s, bell furnace in our country has changed from introducing andassimilate foreign products to independent design and manufacture. But some restrictiveproblem still exists in design and application as well as improvement of full-hydrogenannealer furnace: pool annealing quality, prone to appear bonding and oxidation colorphenomenon of the steel coil, the full-hydrogen annealer furnace annealing curve of thesteel coil can only rely on production experience to formulate at present, without a scientificand reasonable formulation and evaluation method. To solve these problems, studies areconducted on simulation and optimization of annealing process of full-hydrogen bellfurnace.The development of the full-hydrogen bell furnace domestic and overseas was reviewed inthis paper, and various aspects of the research work are analyzed and assessed, such asannealing process curve formulation method, problems occur in the annealing process andso on, which laid the foundation for the subsequent research. Then, studies are conductedfrom the following aspects:First the structure of the full-hydrogen annealer furnace is introduced and the workingprocess of the full-hydrogen annealer furnace and phenomenons often appear during usagesuch as inner cover breakage is analysised. Then the computer numerical calculationmethod was used to simulate the combustion space of the heating process of thefull-hydrogen annealer furnace. Numerical simulation results show that the existingcommon full-hydrogen annealer furnace burner is divided into two layer uniformarrangement in the burner lower, this causes full-hydrogen annealer furnace combustionspace corresponding lower appear local high temperature region, which makes the innercover uneven distribution of temperature, easy to cause damage. If the burner is divided intomultiple rows of evenly dispersed layout in heating hood, then can reduce the temperaturedifference in different height position of the furnace, make temperature distribution moreuniform, which is good for the inner cover to transfer heat to steel coil.Then the energy coupling analysis has been made on the working process of thefull-hydrogen annealer furnace, and temperature calculation model, heating covertemperature calculation model, cover temperature calculation model, protective hydrogen temperature calculation model, cooling cover temperature calculation model and steel rolltemperature calculation model of the full-hydrogen annealer furnace are establishedaccording to the characteristics of its working process. Then according to all kinds of theestablished full-hydrogen annealer furnace mathematical model of annealing process,designed annealing curve formulate program, this program can be realized on the basis ofthe existing steel coil annealing process each phase time calculation for steel coil in theprocess of annealing temperature, or according to the steel coil annealing temperaturecalculated demand of steel coils annealing process of each stage duration. This article testedthe result of the computation program with the field test data, and the results indicate that,this full-hydrogen annealer furnace annealing curve formulate program for the calculationof the result is reliable and reasonable.For the steel roll bonding and oxidation color defect that is now widely existing in thefull-hydrogen annealer furnace, the reasons were analyzed and summarized in this paper,and analyzed with the test data got in a insert experiment, indicate that, steel coil annealingprocess curve set is not reasonable, and steel coil annealing process of thermal stress is themain reason cause steel roll bonding. And steel roll are premature is the main reason causeoxidation color.In the end of this article, regenerative cross combustion technology is applied tofull-hydrogen annealer furnace, a new type of full-hydrogen annealer furnace heating coveris designed. The original burner system, heat pipe heat exchanger system of thefull-hydrogen annealer furnace is changed to regenerative burner, scattered layout in heatinghood. The advantages of the new full-hydrogen annealer furnace heating cover are save fuel,combustion chamber temperature uniformity, steel coil annealing are of good quality andinner covers have long life.