Applied Mechanics and Materials Vols. 80-81

Abstract: The applicability and accuracy of whole set oil-immersed pump lectotype are the key points to improve the recovery ratio of oil field and to conserve energy. This paper have conceived the construction and implementation of the expert system of whole set oil-immersed pump lectotype and discussed in several aspects: such as systematic analysis and design, the construction of engineering control platform, the development of plug-in software, the construction of intelligent system and the execution of software design and so on. It has integrated the synthetic approach with expert System of Whole Set Oil-immersed Pump lectotype.

Abstract: In this paper, the basic theory of Virtual Design was described and the application of 3D design software SolidWorks 2009 in loader working device was introduced as well. In SolidWorks 2009, Loader working device was taken for example to discuss the process of parametric modeling. Meanwhile, it could be approved from the virtual assembly process of working device that the whole process was fully in line with the assembly process in actual production.

Abstract: Many factors influence WEDM(Wire-cut Electrical Discharge Machining) machining precision, and the influence of various factors on the machining precision are expressed by wire electrode dynamic form ultimately. In this paper, the transverse vibration theoretical model of the axially moving electrode wire coupled with thermal stresses is established by the principle of Hamilton. The influence of various processing parameters on machining precision are analyzed and simulated. This study provides a relevant theoretical basis for optimizing processing parameters, reducing the wire vibration and improving machining precision of workpiece.

Abstract: According to the limit working conditions of the gantry milling machine column, this paper adopts Parametric Design Language APDL to set up finite element model and make finite element analysis. Based on the analysis, the topology optimization method of column structure is proposed, and the optimal design method is established to minimize the weight. The finite element analysis is made again to analyze the rearranged column structure. Compared with the design made through experience, optimally designed column can reduce 10% weight. And the critical displacement and maximum stress are not affected.

Abstract: Due to absence of an integral mathematical model, quality control in spinning process has been hard problem for a long time. Rough sets theory (RST) is a methodology that effectively deals with the problems with inexact, uncertain or vague knowledge in a complex information system. Considering a mass of data from spinning process and inspection, as well as the variety of knowledge and experience from domain experts, an RST-based intelligent control model for spinning process is presented in this paper. In order to analyze the yarn strength when the characteristics of fibers are given, a rule extraction method based on RST is researched. The logical rules extracted from the decision table indicate that the initial strength of fibers is a key factor influencing on the yarn strength. At the same time, the different values combination of the final reduced attributes also obviously influence on the yarn strength in different degree when the certain nominal yarn is being processed. Therefore, RST method can be taken into account for spinners to choose suitable fiber materials in order to ensure the quality and reduce cost.

Abstract: A novel adaptive force control table for rotary ultrasonic machine tool was developed for processing micro holes. The adaptive force control table, a mechanical balancing device by which the load can be adaptively adjusted without numerical control was adopted as an attachment in an ultrasonic machine tool. To verify the performance, micro holes were drilled on SiC workpiece. The drilling force, tool wear and profiles of these machined micro holes were investigated. According to the experimental results, it is confirmed that the newly developed table attached on the ultrasonic machine tool is an economical and efficient approach for machining micro holes on hard and brittle materials.

Abstract: This study aims to analyze the relevant mechanical properties of woodball shafts by applying numerical methods. The structures of woodball were constructed in Solidworks 2007 to form the solid models, and the numerical model was analyzed in ABAQUS to acquire the simulation resluts. The collision speed between ball and mallet was from the experiment of motion analysis. As the maximal stress of mallet was concentrated in the proximal part of bottle, some enforcement design could be carried out in this part to reduce the fracture incidence. Another important finding is the contact area at the mallet head was really small, the rubber cover at head part may thicken at the centre part and thinner at the outside area. For further study, it is important to represent the higher fidelity of the input conditions for the finite element analysis (FEA).

Abstract: Deep drawing of square boxes of tailor-welded blanks (TWBs) was studied by experiment and simulation in this paper. When the tailor-welded square boxes with different thickness was drawn to square boxes, the weld seam moved towards the thick part on the bottom and towards the thin part on the wall of square boxes. If the blank-holder force was very small, the wrinkling will happen on the thin part. If the blank-holder was very large, fracture will occur on thin part. Draw beads and non-uniform blank-holder force were investigated to control the deformation of the TWBs workpieces in this paper. When using the draw beads during TWBs drawing, using draw beads in both sides was better measures to control the movement of the weld seam. When non-uniform blank-holder force was used to control the movement of weld seam of tailor-welded blanks, it should be choice that the non-uniform blank-holder force on thick part was a half of that on thin part. It was shown that draw beads give better effects on the control of TWBs drawing than other methods. The variation of thickness was little in the bottom, and the variation of thickness was obviously in the corner of bottom. The maximal variation of thickness of TWBs workpieces on different area was both about 90.1%.

Abstract: Five-axis turning-milling center is an important and advanced NC machine in fields of military industry, aerospace, automobile and medical machinery. The model of machining center is established by using ADAMS and designing the variable parameters. The error of machining center is simulated by Monte Carlo method. The command file is compiled to simulate the machining center and the motion reliability is computed using simulation results. The whole process avoids establishing and solving complicated mathematical equations. So, it is an effective method for the analysis and computation of motion reliability. Compared with traditional methods, this method is more accurate and quick and it is suitable for complicated mechanism.

Abstract: This paper presents a novel model of lay out of cutter head of TBM(tunnel boring machine). Rock-broken mechanism during the operation of the cutter head is analyzed to study the layout of cutters. A model of the cutters under the action of forces during TBM’s working has therefore been developed, thus proposing a scheme to improve the rock breakability of TBM’s cutter head on which the cutters are lay out. Then, a nonlinear multi-objective mathematical model with complex constraints is developed, with an optimization program provided via an intelligent algorithm for the layout design of cutters on the cutter head of a TBM. The cutter head of an EPB6.28 TBM, an optimized design is given to set up a prototype with digitized cutter head, to which a simulation is done for the verification of equilibrium of forces. Comparing analytically the cutter wear and equilibrium of forces between a previous and a newly designed cutter heads, the results shows digitally that the new one is more practicable than the previous one.