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Inner-and-outer steel flange has gained many attentions in China. This type flange has both inner and outer rings, as well as bolts. To gain insight into the intrinsic characteristics of the flange, an experimental study is conducted, taking into account that the tension and bending loads are imposed simultaneously. The varying of relative displacement between two adjacent flange planes with external loading is surveyed. It is indicated that the deformation is almost linearly increased with the external loads, if there is no yielded bolt. Strain gauges are employed to capture the strain distribution in the ribs as well as the tube. The internal tension force of bolt is also measured in the test. It is revealed that the failure mode of the flange is the breaking of the outer bolts. Moreover, the existence of the tension load would reduce the bending bearing capacity of the flange, and prying force could be ignored. It is concluded that the plane-section assumption holds approximately. Accordingly, formulas are given to compute the bearing capacity of the flange. It is found that the computing method is quite conservative if the position of rotation axis takes a value of 0.8 times of the diameter of the steel tube.

In order to understand the characteristics of fire whirls in the inclined shaft with corner gap, large eddy simulations (LES) of thermal flow field in a 9-meter-high inclined shaft were employed. In the inclined shaft, the conrner gap is 0.3m and 0.7m in width, and the inclination angle is 5°, 30°, 45°, 50° and 55° from the vertical orientation axes respectively. It is found that a whirling flow field could be formed under proper inclination angles and corner gap width. Rotational axis of fire whirls in the inclined shaft would have same inclination angles with the shaft. Similar to the case of fire whirls in a vertical shaft, the width of corner gap of inclined shaft also influences the whirling motion of the flame. In this paper, for the same fire and inclination angle, the 0.3-meter-wide corner gap is easier to form stable fire whirls than the 0.7-meter-wide corner gap. By comparison with buoyancy, the slightly greater Coriolis force was found above a height 3m for inclined fire whirls when the width of croner gap is 0.3m, however, the Coriolis force acts only on the lower part of the shaft when the width of croner gap is 0.7m.

This paper presents how in the Reverse Engineering process can be integrated specific software tools, developed by the authors, which allow for digitized rectangular parts with internal surfaces of revolution, to obtain solid models and CNC program. The first tool named Rotational Axis Primitives and Recognition has implemented a set of algorithms and it is used for recognizing, from a cloud of points associated with a rotational part, the axis and geometrical parameters. The second tool named Hole_Application is created for forward engineering and it can be used to design and manufacture the industrial products with rectangular shape using intelligent technological objects for holes.

Recently, the idea of sustainable development has become more and more important. In the previous report, we focus on downsizing industrial goods and discuss the environmental load of industrial goods. As a result, by downsizing machine tools we verified that the environmental load of mother machines in making copies of themselves could be reduced. On the other hand, we verified that the environmental load of use of the machine itself increased relatively. Thus, in desktop machine tools, we verified that reducing the environmental load of use of the machine itself would increasingly become an issue in the future. In this paper, we discuss methods of using desktop machine tools from the aspect of power consumption. As a result, we verified that in cutting along the linear-axis and rotational-axis, we have to consider back clearance after cutting.

The robot joints are usually rotational axis by two link joints, bionic features is not strong. The shortcomings of intelligent MR damper control multi-axis bionic knee can only provide resistance and certain sizes of regain momentum, cannot provide larger power, therefore this paper gives by the multi-axis four-bar structure, ball screw transmission hybrid drive multiaxial bionic active knee institutions. And analysis the human leg institutions and commonly used two-bar structure, solve the ball screw transmission installation location parameters. And established based on hybrid drive of the bionic active the knee's virtual prototype.

The purpose of reverse engineering is to convert a large points cloud into a CAD model. Parameters extraction for rotational surface from measure data is an important problem in reverse engineering. Rotational axis is a crucial parameter of rotational surface. In this paper, random sampling consensus algorithm combined with Least-Squares method is used to extract the rotational axis of rotational surface. Experimental results show effectiveness, robustness and accuracy of this proposed approach.

Micro machining by wire electrical discharge machining (WEDM) has become prosperous owing to its ability to machine conductive, exotic and high strength and temperature resistive (HSTR) materials with the scope of generating intricate shapes and profiles. In order to achieve the very high accuracy micro machining, one of the key factors is the preparation before actual machining. According to the authors' experiences and studies in micro machining by WEDM, for the first time, this paper introduces the preparation process for WEDM in micro machining. From the gauge setup, wire alignment adjustment, working coordinate setup to calibration method for rotational axis, the preparation process has been studied and introduced in detail, which forms the solid basis for high accuracy micro machining by WEDM. Experimental results show the accurate geometrical features can be fabricated based on the proposed preparation process.

Considering gyroscopic effect and flexibility of the shaft, the eight freedoms dynamic model is established. The dynamic characteristic and control quantity in different bearing rigidity and rotation axis are studied and discussed by optimal control theory. Furthermore, the controlling and the responding are discussed. The simulation results show that the bearing rigidity has great effect on the control quantity so that the elasticity of bearing must be considered. The asymmetry rigidity of rotational axis has little influence on stability. The conclusion may bring up theoretical references for precision control for rotor magnetic bearing system.

Truing and dressing are essential processes of grinding wheel preparation. They make the wheel geometry true with respect to its rotational axis and its cutting surface sharp. These factors significantly influence the quality of the final profile and surface produced from the grinding process. Prediction of the optimum wheel surface for grinding, defined as one which produces an accurate profile and cuts most efficiently can greatly minimize the time to optimize grinding wheel performance. This paper describes virtual dressing and truing operations, takes under account vibration of the dressing apparatus and shows how to generate wheel surface replica under different conditions.