Research On Key Technology And Project Practice Of New Type 60m~2 Non-Arching Sintering Machine

With the increasing yield of steel and iron, the sintering machine supplying raw materials for the blast furnace is becoming more important. The draught mechanism of pallet cars is the core mechanism of the sintering machine, which directly affects the running of the sintering pallet cars and regular production of the sinter. In this paper, the draught mechanism of the Lurgi sintering machine is introduced and the problems during the course of operation are presented. In order to solve these problems, effective methods are proposed. Therefore, the research fruits have great theoretical and practical value not only for increasing the sinter production, but also for design, manufacture, installation and debug of the new type non-arching sintering machine for the future.Firstly, the development contents of the new type non-arching sintering machine are introduced, including the design of new type front and back sprocket wheels, the design of the wheel roadway, the force control method, the design of force control device to solve the arching of lower pallet cars and the determination of the fundamental parameters of the new type sintering machine, etc..Secondly, the research results show that the new type front and back sprocket wheels can not only effectively resolve the velocity fluctuation of the pallet cars but also make their contribution to decrease the arching of the lower pallet cars. Hence, 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 with sectionalized is established and expressed by universal equation. Aimed 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 60m2 sintering machine are designed and manufactured.Thirdly, by analyzing the mechanics relation between the back sprocket wheel and the upper and lower pallet cars, the non-arching mechanics model of the lower pallet cars is established. The force control methods of imposing the torque-loading on the main shaft of the back sprocket wheel and correctly collocating the back additional weight are brought forward to carry out the non-arching of the lower pallet cars. By the multi rigid body simulation for the pallet cars'draught mechanism of the new type 60m2 sintering machine, the time depended curves of the torque acted on the main shaft of the back sprocket wheel and the no controlled and controlled thrust forces brought bear from the back sprocket wheel to upper and lower pallet cars are gained, respectively. Meanwhile, basic data used to design new-type 60m2 non-arching sintering machine are obtained on the basis of a set of force control values。From the visualization, the simulation also proves that the mechanics model is correct, and that the force control methods are effective to eliminate the arching of the lower pallet cars. The force control database established according as the structure size and conversion quality of the pallet car of series type sintering machines offers certain reference value for the engineering design of the non-arching sintering machine.Lastly, based on the determination of the actuator of the hydraulic torque-loading device on the main shaft of the back sprocket wheel and the connection mode between the loading device and the main machine of the sintering machine, the working principle of the loading device is also elucidated in detail. Taking the new type 60m2 sintering machine for example, the installation of the hydraulic torque-loading device is elaborated and the choice of the key hydraulic components is expatiated. Moreover, industry test is proceed for the new type 60m2 non-arching sintering machine, including the installation and the running situations after installation of the sprocket wheels with even number and varying teeth space, the method of united debug test on hydraulic torque-loading device and back additional weight and the detailed analysis of the observed data, and so on. The debugging achievements attained in the field industry test about the new type sintering machine attest the correctness and reliability of the theories in this paper. Simultaneously, the shortages occurring in the debug stage also are illuminated。...