High-precision Thickness Setting Models for Titanium Alloy Plate Cold Rolling without Tension

Due to its highly favorable physical and chemical properties,titanium and titanium alloy are widely used in a variety of industries.Because of the low output of a single batch,plate cold rolling without tension is the most common rolling production method for titanium alloy.This method is lack of on-line thickness closed-loop control,with carefully thickness setting models for precision.A set of high-precision thickness setting models are proposed to suit the production method.Because of frequent variations in rolling specification,a model structural for the combination of analytical models and statistical models is adopted to replace the traditional self-learning method.The deformation resistance and friction factor,the primary factors which affect model precision,are considered as the objectives of statistical modeling.Firstly,the coefficient fitting of deformation resistance analytical model based on over-determined equations set is adopted.Additionally,a support vector machine（SVM）is applied to the modeling of the deformation resistance and friction factor.The setting models are applied to a 1450 plate-coiling mill for titanium alloy plate rolling,and then thickness precision is found consistently to be within 3%,exceeding the precision of traditional setting models with a self-learning method based on a large number of stable rolling data.Excellent application performance is obtained.The proposed research provides a set of high-precision thickness setting models which are well adapted to the characteristics of titanium alloy plate cold rolling without tension.

NEW TECHNOLOGY AND MACHINE TOOL FOR THE FORMING OF THE REAR AXLE SHAFT OF LIGHT TRUCK

A new technology of forward extrusion and cross rolling has been developed to process the rear axle shaft sleeve of light truck with the use of tube billets. This technology is characterized by large reductions of material, energy and cost of production and has significant economical benefits. This technology is stable and reliable. The three rolls transverse rolling mill built based on this technology has novelty construction, higher production efficiency, non-vibration and noise. The research results have been extensively applied to light trucks and farm transport with load of 1 to 3 tones.

Mechanical model for double side self-propelled rolling machine based on rigid and flexible contact dynamics

The objective of the present research was to establish a mechanical model to study the performance of double side self-propelled rolling machine.There are two key models in the modeling process.The first model is the soft cover dynamics model,which is an important innovation in this study.And the insulation quilt was established based on the Macro-modeling technology.The second model is the double side self-propelled rolling machine virtual prototype model.By specifying multiple contact constraints and loadings between the soft cover dynamics model and the rigid component,the virtual prototype model was built successfully and the double side self-propelled rolling process was completely simulated.Moreover,the interaction mechanisms of the rigid and flexible coupling mechanics were investigated.The virtual rolling processes of different insulation quilt lengths were analyzed under different thickness treatments.The simulated results showed a good agreement with the experimental measurements,which suggested that the established model is an effective approach to evaluating and optimizing the rolling machine.The successful establishment of the mechanical model can facilitate the study of the performance of the product and further optimization,and also is of great significance to shorten the development cycle and reduce costs.