Research On Key Technology And Project Practice Of Sintering Apparatus

Mixer and sintering machine is the core equipment of sintering plant. With the large-scale of equipment and increasing of blast furnace volume, the strength, particle size and chemical composition, especially smelting characteristics of charging including iron are called for increasingly high quality. Therefore, as necessary equipments of producing high quality sinter production, mixing and sintering equipments becomes particularly important. Constantly expanding scale of blast furnace causes many problems. After a long period of continuous operation, material in mixer sticks to inner wall and is difficult to be removed. Meanwhile, the granulating effects of mixed materials are very poor and sever wear of rubber tires occurs. Air leakage of sintering machine leads to a decline of sinter quality, decreasing of production and increasing of return fines ratio and energy consumption. So, it has a direct impact on the production of blast furnace.Aiming at above problems, research works were carried out as follows:Firstly, the movement of material during mixing and granulating was analyzed and it's six motion states in mixer were summarized. Based on the influence factors analyzing for uniform mixing and granulating of drum mixer, optimal operation parameters of mixing and twice-mixing were lucubrated and the process was optimized.Secondly,the author analyzed the radial mechanical properties of mixing drum cylinder and derived from calculating method of radial force. Under analyzing axial force of cylinder of drum mixer, three-moment equation was proposed. Combined with the force of tire and its radial displacement, these equations used to solve the force of support tire were established. The results obtained by the method seem more tally to actual operation. Furthermore, the effects of sliding frictional force between cylinder and tire on wear also were analyzed and calculation example was given. Pressure distribution between all support tires, stress, strain, and displacement of tires were simulated with ANSYS. And the relation curve between force of tire and radial displacement was educed. Thirdly, by analyzing air leakage and seal forms of sinter machine, author presented the sealing technique of head and tail of sinter machine for the first time and magnetism-fluid sealing was utilized on the bellows chute. All the measures and technologies have been applied in tens of steel enterprises. After a long period of testing of sealing, air leakage rate has a obvious decreasing and a good effect was achieved.Finally, two kinds of teeth space arranged alternately and the even number of teeth are determined for the sprocket wheel according to the interval changed wheelbases of the rolling wheels in the pallet cars. By combining the meshing principle with the actual working condition between the sprocket wheel and the pallet cars, the practical tooth profile curve is established and expressed by universal equation. Aiming at the tooth surface damage of the sprocket wheel while working, the contact stress of the tooth surface is calculated by using the Hertz theory, and various measures to improve the load capacity of the sprocket wheel tooth surface are studied. The distributions of the contact stress simulated with nonlinear FEM in the ideal working condition and the actual working condition show further that the damage reasons of the tooth surface and prove the availability of the methods for improving the load capacity. Based on the study results mentioned above, the front and back sprocket wheels with even number of teeth, varying teeth space and high load capacity for new type sintering machine are designed and manufactured. The speed fluctuation of pallet cars of belt-type sinter machine was effectively solved. It is more important that the arch problem of lower pallet cars was also eliminated and bearing capacity was also increased.