Research into Technology of Bao Steel's Pickling Tension Leveler

According to the survey of Bao Steel's pickling tenstion leveler,the technology of the tension leveler is analysed systematically.In order to solve the problem which hinders the production,the given technological parameters of this leveler have been improved and good results achieved.

Numerical simulation on the process of multi-point forming for tube

To apply the multi-point forming technology to the field of tube processing,the process of multi-point forming for tube is studied.Numerical simulation for the process of multi-point forming for tube is achieved by using elastic-plastic FEM in ABAQUS.During simulation,reasonable coefficient of mass scaling and friction model of penalty function are used.The influence of several major technological parameters on the process is analyzed.When the tube diameter is 60 mm and the forming curvature radius is 1000 mm,the distortion rate of cross-section and the absolute forming error gradually decrease with the increasing of tube wall thickness;However,when the tube wall thickness is constant,the smaller the curvature radius,the larger the distortion rate of cross-section,but as to forming part,its absolute forming error becomes smaller.

Effect of technological parameters on optical performance of fiber coupler

To find out the influence of technological parameters on optical performance of fused optical fiber device, the fiber coupler was served as subject investigated by using the fused biconical taper machining as experimental setup. Fused fiber coupler's optical performances such as insertion loss, excess loss, directivity and uniformity were tested with the optical test system that was constituted of tunable laser and optical spectrum analyzer. Especially the relationship between optical performance and drawing speed was investigated. The experimental results show that the optical performance is closely related to process conditions. At fused temperature of 1 200 ℃, there exists a drawing speed of 150 μms, which makes the device's performance optimum. Out of this speed region, the optical performance drops quickly. At drawing speed of 200 μms, the excess loss is relatively small when the fused temperature is above 1 200 ℃. So the technological parameters have close relationship with optical performance of the coupler, and the good performance coupler can't get until the drawing speed and fused temperature match accurately.

Numerical prediction of the incremental melting and solidification process

A mathematical formulation is applied to represent the phenomena in theincremental melting and solidification process (IMSP), and the temperature and electromagneticfields and the depth of steel liquid phase are calculated by a finite difference technique using thecontrol volume method. The result shows that the predicted values are in good agreement with theobservations. In accordance with the calculated values for different kinds of materials anddifferent size of molds, the technological parameter of the IMS process such as the power supply andthe descending speed rate can be determined.

BP Neural Network of Continuous Casting Technological Parameters and Secondary Dendrite Arm Spacing of Spring Steel

The continuous casting technological parameters have a great influence on the secondary dendrite arm spacing of the slab, which determines the segregation behavior of materials. Therefore, the identification of technological parameters of continuous casting process directly impacts the property of slab. The relationships between continuous casting technological parameters and cooling rate of slab for spring steel were built using BP neural network model, based on which, the relevant secondary dendrite arm spacing was calculated. The simulation calculation was also carried out using the industrial data. The simulation results show that compared with that of the traditional method, the absolute error of calculation result obtained with BP neural network model reduced from 0. 015 to 0. 0005, and the relative error reduced from 6, 76 % to 0.22 %. BP neural network model had a more precise accuracy in the optimization of continuous casting technological parameters.

Investigation and Application of Non-sinusoidal Oscillation Technique of Mold

To improve the slab quality, a kind of non-sinusoidal oscillation technique of mold driven by elliptic gears was developed. The waveform functions of non-sinusoidal oscillation were determined, and the calculation method and curves of technological parameters for non-sinusoidal oscillation were given. At the case of waveform deviation factor a equal to 0.31 and oscillation amplitude h equal to ±2.7 mm, the relationship between oscillation frequency and casting speed is determined, and the technological parameters for non-sinusoidal oscillation are calculated. The testing results of industrial application indicated that this technique could not only improve the Slab surface quality, but also reduce the steel breakout.

Effect of Nb on Austenite Recrystallization in High Temperature Deformation Process

By analyzing the stepped test pieces with optical microscope,the influence of the technological parameters including rolling temperature and reduction on the austenite recrystallization fraction of steel with Nb content of 0.08% deformed at high temperature processing was studied,and the deformed austenite recrystallization figures of the test steel were obtained.The result indicates that when the reduction is 60%,the critical temperature of complete recrystallization is 1070 ℃ and the borderline temperature of non-recrystallization is 900 ℃.In contrast with general HSLA steel,the recrystallization and non-recrystallization temperatures are respectively 120 ℃ and 100 ℃ higher than those of ordinary HSLA,so the steel with high content of Nb has better hot processing performance because Nb has great function of holding back recrystallization.