Jin Wei Fan

Analysis of Major Defects and Nondestructive Testing Methods for Solid Rocket Motor

The paper introduces the major defects and its causes of solid rocket motor,the harm and effects of the combustion chamber defects for the stability of motor were clarified,the main methods and their advantages and disadvantages of defect detection currently used in solid rocket motor are also cited and analyzed, and it points out the developing trends about various of detection technology used in conjunction.

Performance of Hydrostatics Spindle under Effect of Mass Unbalance

The static and dynamic model of spindle system is established in order to analyze the vibration response with the effect eccentricity of spindle. Natural frequency of spindle is calculated with ANSYS software. The variation of thickness and stiffness of oil film are analyzed, and the dynamic response is deduced. The deflection of spindle i.e. the machining error caused by the eccentricity is obtained. Key words: Hydrostatic bearings; Dynamic response; Stiffness; Deflection

Geometry Error Parameters Identification Methods of 3-Coordinate CNC Machine Tools

It is inevitable that the mechanical part has error when machining. To increasing the machining precision and decreasing the shape and position error, error compensation is one way. The geometry error parameter is necessary when the error compensation model is founded and the compensation data is calculated. The common measuring and identifying methods are introduced in this article. Their mathematic models and solutions are listed and their merits and drawbacks are compared. This method has been applied in CNC error compensation and the effect is advisable.

A Kind of Multi-Functional Wall Surface Nondestructive Testing Device

In this paper, non-destructive testing on the inner wall surface of the deep, invented a detection device, the device by numerical control systems, mechanical control devices and imaging device components. PC lower machine controlled by CNC system mechanical devices IPC and PLC can control the composition includes a manual lift the car up and down movement, control multistage axial movement of the cylinder and the axial rotation of the servo motor control to meet the imaging device the location requirements. Imaging device consists of a high-speed industrial cameras and miniature camera components. The device has a low cost, high accuracy, simple manufacturing process and so on.

CNC Cylindrical Grinding Machine Reliability Analysis and Optimization

CNC cylindrical grinding machine reliability is an important performance indicators, the level of reliability will directly affect the use of CNC cylindrical grinding machine. Reliability of the traditional classification method is not clear, standards are not uniform, the paper application taxonomy for 12 CNC grinding machines from September 2012 to July 2014 for two years more than 600 pieces complete failure and repair data for statistical analysis to identify a greater impact on the overall reliability of the fault location and cause of the malfunction. According to the probability of occurrence of each failure mode, the severity of harms comprehensive evaluation of the degree of fault of each site, identify the weak links of the whole system. As a result, the reliability of CNC cylindrical grinding machine will be greatly improved.

Robust PID Parameters Optimization Design Based on Improved Particle Swarm Optimization

The article, based on satisfying robustness of the system and put forward the objective function of time-domain performance and dynamic characteristics, introduced genetic operators into Particle Swarm Optimization. The algorithm improve the diversity of particles by selection and hybridization operations and strengthen the excellent characteristics of particles in the swarm by introducing crossover and mutation genes, which can avoid bog down into local optima and premature convergence and enhance searching efficiency. The simulation results indicate that when the algorithm is applied to the optimization of PID controller parameters of servo system of grinding wheel rack of MKS8332A CNC camshaft grinder, its performance is better than the single Genetic Algorithms or Particle Swarm Optimization, and it can also satisfy the demand of rapidity, stability and robustness.

Research on Reliability Growth Technology of CNC Grinding Machine

Based on the collected data to carry on the analysis, found that the CNC system in the CNC grinding machine fault rate, a large part of the station, the reliability growth of CNC system is studied in the paper, CNC system parameter selecting principles of reliability growth are particularly discussed. CNC system reliability ideal growth curve is settled to CNC system reliability, Thus increasing CNC system to improve the reliability of CNC grinder machine reliability is of great significance.

Research on Analytical Method of CNC Machine Tool Precision Recession

The focus of this paper is to find a new method analyzing the reasons of CNC machine tool precision recession. The modeling of the movement error of CNC machine tool is one of the most important problem for kinematics designing and accuracy analysis. In this dissertation, this study analyzes the six movement error parameters of guide and the model of the guide which including foundation deformation, material’s natural ageing and way rub has been established. A detailed example is given for the modeling precision recession of 3-axis CNC machine tool.

Modeling of Geometric Structure for Numerically Controlled Grinder Based on Multi-Body System Theory

According to the multi-body system theory and geometric topology analysis method, combining the geometric structure and working principle of thread NC grinder, made the kinematics analysis for each parts of NC grinder. And the mathematical model for geometric topology structure of grinding machine system was established; the precision machining equations of NC grinder was deduced. Furthermore, the paper used the coordinate transformation principle of homogeneous to deduce the precision processing equation of NC grinder, all of that was based on the moving relationship of the machine tool, the workpiece and the grinding wheel, and got a kind of method that it can use multiple line grinding wheel to grind small radius, small screw pitch and multiple thread. This method laid a theoretical foundation for NC grinder machine processing which used multi-line grinding wheel to grind threads, and improve the grinding efficiency and precision of multi-line grinding wheel; in addition, this method has obtained good effect in grinding thread production.

Profile Study of Formed Milling Cutter for Screw Based on Non-Instantaneous Envelope Method

Through analyzing the shape of screw of oil extraction progressing cavity pump, the spiral surface equation of screw was established; and from the relative motion between formed milling cutter and screw, the basic profile equation of formed milling cutter was established with the method of non-instantaneous envelope. According to the actual use of formed milling cutter, aim at the problem of wear for formed milling cutter, established profile equation of front cutting edge and constant back cutting edge, and finally to get a complete profile equation of formed milling cutter. The correctness of milling cutter profile is ensured by interference checking for profile equation of formed milling cutter. The profile equation of formed milling cutter provides a theoretical foundation for the design and manufacture, and it would have great significance to the actual production.