Papers by Author: Zhi Wei Zhang

Abstract: A new structure of ship motion simulation platform and its hydraulic control system were designed. Matlab/Simulink was used for the analyses of hydraulic control system. Virtual prototype of the ship motion simulation platform was built up by ADAMS under the seasickness test condition, and the kinematics analysis was also carried on. The results show the effectiveness on the model of platform.

Abstract: According to the testing craft and requirements of CNC Lathe about main spindle box, testing system of hardware and software structure was designed in this paper. It adopts sensors, data acquisition cards, industrial control computer, frequency converter and so on as hardware, good data analysis methods, and LabVIEW as software tool, to realize real-time monitoring of main spindle box testing conditions.

Abstract: In fluid hydrostatic closed-type slideways systems, restrictor will take an important role of improving the performance of machine tools. Generally there are four types of restrictors to be utilized, capillary type, orifice type, slot type, and dynamic feedback type. The general oil film stiffness model of different types of restrictors was constructed and the characteristics of different types of restrictors are analyzed and compared. The analysis results demonstrated that the stiffness of restrictors depend on the geometry and structure parameters, and according to the analysis results the all types of restrictors can be designed optimally.

Abstract: Electroslag Remelting (ESR) technology is a main method of special metallurgy; and split pillar is one of the most important mechanical units of ESR. The split pillar works not only as the mother body of ESR cross arm, but also as the rotation driving device of the cross arm. Since the tremendous mass of the cross arm and electrodes, serious inertia torque generates when the split pillar rotates, which leads to motion instability and problems of angle location and even safety threatens. In this paper, based on virtual machine technology, dynamic research of the rotation process of the electroslag-remelting-furnace split pillar was proceeded; influences of driving torque applied on the split pillar was researched, as the driving torque being constant, anti-step and with brake torque. 3D solid model of the split pillar and clamping device were established; main technical parameters were accomplished; and simulation research of the dynamic process was proceeded. It was found that, appropriate brake torque was important to better motion stability of the split pillar. The best brake torque was acquired, and the action time of the brake torque was obtained.

Abstract: This article is to provide a method to make the structure of machine tools lightened and improve its anti-vibration capacity. Modal analysis with pre-stress of High-speed Turning Center’s spindle box was performed using ANSYS Workbench; based on the above results, we optimized the spindle box using topological optimization and dimensional optimization methods. Finally, we make the spindle box’s weight reduce by 4.44%, its first order frequency increase by 15.82%, its first mode maximum amplitude decrease by 9.18%.

Abstract: The necking-in product is widely used in many fields in the world. An improved necking-in machine is introduced in this paper. Matlab/Simulink is the popular simulation software in the dynamic system simulation field due to its powerful computing capability. DSHplus is the hydraulic special simulation software with graphical programming environment and abundance of model libraries and the system model can be built quickly. The co-simulation of DSHplus and Matlab/Simulink can take the advantage of their merits, which can study the control algorithm that applied on the hydraulic proportional system better. The Fuzzy PID control algorithm can apply logistic inference to tune the PID parameters automatically according to the working condition, which can solve many engineering problem of high performance requirements. So the Fuzzy PID algorithm is applied in this paper to improve the performance of the hydraulic system.

Abstract: Oil mist lubrication is currently widely used as a lubrication method now. It has some advantages as follows: low fuel consumption, uniform lubrication and high efficiency. In job site, oil mist condensation occurs in the pipeline, and this will not only reduce the efficiency, but also lead to accidents. Nowadays, CFD numerical simulation software has been widely applied in design, but the research of oil mist condensation in the transmission process based on CFD is very fare. In this paper, to choose the right the working parameters and a reasonable pipeline layout in job site, the oil mist condensation in the pipeline was simulated based on CFD. And it was found that, the diameter of oil mist particle is mainly influenced by temperature, and the best temperature range is made out.

Abstract: The density of oil mist in this paper is an important factor of oil mist lubrication technology, according to which the effect of lubrication will be known and from which the study on atomization effect will also benefit. In general, the oil mist density of oil mist lubrication system in working condition is 3-12g/ m3 , the median diameter is 1-3 [1], which is difficult to measure with conventional detection methods. The paper takes advantage of optical rotation principle as a measuring method for density of oil mist and achieves a good experimental result.

Abstract: The core of shape control depends on the control of the rolling seam. At present, bending rolling control system is used extensively. It mainly depends on the hydraulic cylinder which generates bending rolling force to improve the shape. The dynamic characteristics of bending rolling force have a big influence to the shape. This paper builds the theory modeling firstly, and takes the advantage of MATLAB to simulate and analyze the key characteristics of bending rolling force.

Abstract: Hydraulic grinding saw is a kind of important equipment broadly used in billet precise cutting in metallurgical industry. In order to improve productivity significantly, control feeding speed reasonably, at the same time to compensate the variation of driving torque caused by the change of contacting area between grinding wheel and slab, thus to obtain the optimized match between the feed of the grinding wheel and the driving motor, the application of hydraulic servo system in the control of the feeding speed of grinding wheel is discussed in this thesis. This article introduces the principle of hydraulic grinding saw, brings out the project of constant power PID control based on the relationship between driving torque and motor current. The transfer function of the hydraulic servo system, the optimized PID controller is also worked out. According to the result of simulation analysis, the controlling factors can be well obtained.