Applied Mechanics and Materials Vols. 599-601

Abstract: In order to solve the stub bar defects and improve the material utilization, this paper proposes the method of using billet with circular arc shape on the end face to control the end concavity. It establishes the cross wedge rolling finite element model by DEFORM-3D software, and through the displacement method to analyze the flow law of metal of rolled piece on the end face, and obtains the influence law of end concavity with different circular arc angles by numerical simulation. Finally, it gets the result that the end concavity length decreases with the increase of the circular arc angle. In comparison with the original billet, when the angle is 90°, the end concavity of rolled piece reduces by 69.04%. The results provide a theoretical basis for saving material and achieving the cross wedge rolling production without the stub bar.

Abstract: Basised on the study of effect with different loading ways on v-shaped components forming process. Put forward a kind of split open control loading technology aiming at forming this kind of components. Studied the effect of key process parameters of split open loading on the quality of finish forging, the key process parameters scopeis given by avoid the finish forging defects. Using shunt split open loading process forming v-shaped components, make internal complex mold cavity filled full, improved the deformation uniformity, reduced the forming load.

Abstract: According to the specific structure of the hopper and cylinder of twin screw cone feeder machine, 16MnR and austenitic hopper and machine cylinder and stainless steel 1Cr18Ni9 are used for construction by welding process instead of cast steel ZG310-570 galvanized originally. The weld technology process is formulated. In the process of implementation of the program, the difficulties of the process as follows are solved: Selection the alternative materials; rational design of cooling water structures; form and position tolerances between double cone screw and inner sphere – conical surface, reduction of the difficulty of processing the double cone cambered, welding deformation control, post - weld heat treatment of removal residual stresses.

Abstract: When turning and grinding the long axis with cone thin-walled, they are clamped to be deformation easily and positioned difficultly. Based on the existing theory of clamping with the conical sleeve, we design a new type of fixture in this paper. The outer cone of the fixture cling to the inner cone of the workpiece, it is sealed hermetically at the both ends. The head of the sleeve stretch out of a cylindrical boss, we can use the three-jaw chuck to position it on the machine tool. Also we use the steady rest to fix the end of the sleeve. The steady rest connect with the shell of a rotary joint. The end of the rotary joint screw with the sleeve, the other end of it is connected with a getter pump. It formatted a vacuum between the sleeve and the workpiece by the use of holes around the circumference of the sleeve. The utility model to the fixture used for thin wall conical parts with long shaft.

Abstract: To make up the shortage of the existing calibration equipments of the wave measurement instruments, the WTTVS is designed, and the design of the wave height standard device as a subsystem of the WTTVS is introduced in this paper. The subsystem consists of two invar leveling staffs, a laser range finder and an incremental encode, in which the invar leveling staffs and the laser range finder are used to calibrate the encode. At the same time, the uncertainty of the subsystem is evaluated. As the result, the uncertainty is 3.48mm (confidence probability is 99%), which proves the feasibility of the design.

Abstract: This paper is mainly discussed the establishment of the unified constraint expression of simulation optimization model. Express all kinds of element constraints with unified physical mathematical mapping mechanism, uniform the model representation of product components in each domain and establish the unified expression model, in order to facilitate the follow-up simulation solution of multi-domain constraint system.

Abstract: An automobile will sustain various incentives from the outside and inside in the process of being driven, in which the impact of the wheel and the vibration of engine mainly dominates. This paper gets the inherent frequency through modal analysis on finite element model in a heavy vehicle’s driving cab. And then it conducts the forced response analysis on finite element model by modeling a condition where the vibration of driving cab is caused by outside incentive. Through analyzing, it finds the main response region generated in driving cab when affected by outside incentive. At the same time, it can provide certain theoretical basis for controlling the noise of driving cab in the future.

Abstract: . This study successfully simulated the single crystal copper nanocutting by a rigid body /elastic tools with nose radius at the nitrogen gas environment using molecular dynamics, and analyzed the workpiece temperature distribution and dislocation during nanocutting. After simulations, it can be found that when cutting with the elastic body tool, the tool itself was still distorted slightly, however, the cutting results of the elastic tool and the rigid body tool of the tool are not the same. The chip temperature was highest near the central rake and nose.The workpiece temperature when the elastic body tool cutting was lower; the temperature in the nose and rake plane is the highest, the more away from the nose, the lower the temperature.

Abstract: As the needs of profiled rings continuously increase, studies about profiled ring rolling processes is becoming a hot problem. This paper established a FE model of hot ring rolling process of inner L-shaped ring based on ABAQUS/Explicit software. The reasonable value range of mandrel feed rate is determined at first. Then the deformation characteristics of rings are analyzed and compared in L-shaped ring rolling process under four different ring blank dimensions. Finally, for realizing a steady rolling process and obtaining good dimensions properties of rolled ring, an appropriate ring blank dimension is given.

Abstract: Globoidal indexing cam mechanism is the spatial indexing mechanism of high speed, high precision and widely used in modern machine and automatic production line.But the working profile of the globoidal indexing cam mechanism is not fair for the space curved surface and it is difficult to model. The traditional design method requires a great deal of calculation, and the design process is complexed, we have to repeat the entire design process when changing any parameters, lead to low design efficiency and poor universality. To solve above disadvantages, this paper used the space meshing principle and space coordinate transformation method, based on 3 d modeling software Pro/ENGINEER, using vc + + and Pro/toolkit for secondary development, realize the parametric modelling of globoidal indexing cam mechanism, and the simulation and analysis of the generated cam mechanism.