Papers by Keyword: Accuracy Control

Abstract: In this research work, the analysis of a parallel structure, hexapod type, was studied from the rigidity point of view. The modelling of the structure and the assembly were designed in SolidWorks one of the most used software for the design in the construction of machine tools, automotive and aeronautics field. The modal, the static analysis, forces and moment loading, were performed with ANSYS programme by finite element method, for each of the three studied positions of the structure.

Abstract: For solving the technical problem of accuracy control during manufacturing and vertically matching the curved steel tower of the bridge, this paper studies the accuracy control technique about it, as project example with the world’s first curved steel tower of No.3 Nanjing Yangtze River Bridge in China. Emphatically research the linear control during manufacturing and vertically matching the tower. Advance the conception of the accuracy control and build up an appropriate “Accuracy Control System” (ACS). Expound the contents of accuracy control, procedure and controlling means. Stress the research on the definition of the reference system of the tower, accumulated height error control, accumulated axis bias error control and accumulated torsion error control. Finally, in accordance with the results of accuracy control, give implement principle and method of manufacturing and vertically matching the tower. The check results show that accuracy of the control meets the design requirements and the research results are practical and reliable.

Abstract: In 3DP process, part has a large contour error due to the print machine, printing parameters, the characters of part materials and other factors. In this paper, based on the result from the Part I, the experimental method is used to study on the part contour error by placing 56 cubes in the manufacturing box in 3DP process. When the binder saturation level and the powder layer thickness are fixed, the contour error for cubes in X, Y and Z directions is obtained, and the leaking error compensation value, also means bleed compensation for the binder in different directions are achieved, and bleed compensation is used to calibrate the printer parameters. The case study also verifies the result in 3DP process, which is effectiveness in parts’ contour error compensation.

Abstract: The technique of hull block accuracy control is the main concern for modern shipbuilding. The method of no-excess block construction is introduced in Sevan Driller, the world’s first cylindrical ultra-deep offshore drilling platform. According to the structural characteristics of the drilling platform and production capacity, the partition and construction programs of the hull blocks are proposed. Modeling and drawing for platform in the design stage is analyzed. In the manufacturing stage, the factors affecting the block accuracy include plate-cutting, plate alignment, marking, assembling and welding. Additionally, the range of accuracy controlling aspect and compensation values are confirmed. The application of no-excess block construction in this drilling platform results in the improved quality of the drilling platform, reduced shipbuilding costs and the shortened shipbuilding cycle.

Abstract: The computer aided measuring system is established to evaluate geometrical information of the structure in subsection manufacture. The cloud points data of surface are collected by laser tracker so as to explore continuing data processing software and evaluate the error of dimension and shape, and then the real measuring model, matched by the corner information, is compared with CAD through the best-fit algorithm. The lack of fitting information which will cause the low measuring precision is solved by the least square method constrained by radius in structure with large radius and small central angle. As the research object, the tunnel structure is used in the quality control of manufacturers.