Papers by Keyword: Vibration Test

Abstract: This paper aims at the phenomenon of uneven wear of working roll and the work-side wear is much higher than the drive-side of an acid rolling mill tension leveler for dynamics simulation analysis, analyzes the vibration characteristics of working roll in different process parameters and different bias conditions of rolls and vibration test is carried out to test the rolls by Donghua5920 test-collection system, and combined with the field vibration data of bending roll, points that unilateral severe wear of bending roll is mainly the zero problems of tension leveler.

Abstract: In order to facilitate dynamic analysis of spindle, improve the vibration characteristics of the spindle and achieve the goal of control of spindle motion stability. A spindle vibration testing system is developed with necessary sensor, signal conditioner and data acquisition card based on Labview software in this paper. The spindle vibration testing and analysis system is formed based on virtual instrument graphical programming language Labview. The hardware is reduced in testing process. At the same time, acquisition, processing and analysis for vibration signal are realized, and the costs of hardware are greatly reduced. The testing work is made more convenient and quick by this system, and test is made more intuitive by its real-time display function. It will provide a scientific basis for searching for measures to reduce the spindle vibration and developing a new generation of mechanical structure of the spindle.

Abstract: In this paper, a set of spindle vibration test equipment has been designed by using modern design method, on the basis of in-depth study of spindle vibration source .The device includes three parts: machinery, detection and control .In the mechanical part, using sensor fixed machine mobile systems, the design of the spindle drive part and test board was carried on respectively .In the detection part ,the virtual instrument Labview graphical programming language was adopted to form a spindle vibration test and analysis system, realizing the acquisition, processing and analysis of the vibration signal .In the control part, Yan Hua movement control cards are adopted to realize control of motor speed, through Labview programming.

Abstract: Implants and bone reconstruction have known a great development recently. Synthesized bone tissues must have mechanical, physiological and biological properties closer to natural bone, as much as possible. Bioceramics are materials which fulfill these conditions, being biocompatible with mechanical strength similar to bone. One material widely used is hydroxyapatite. Hydroxyapatite is slightly different from bone tissue and it forms the mineral part of bone tissue. In order to improve mechanical properties and biological compatibility hydroxyapatite is doped with different compounds, mainly chemical elements. Magnesium, a chemical element present in human bone structure is one of these compounds.

Abstract: In view of the structure and running characteristics of gearbox of large and special crane, we have respectively carried out vibration test of fault and free-fault gearbox containing planetary gear in the work. With the help of Matlab engineering software, we can read and process the collected vibration signal of gearbox and draw the time-domain and frequency-domain graph. Through the comparative analysis of vibration information of gearboxes, we can determine the link between fault type and signal characteristic value, effectively realize the fault diagnosis of gearbox.

Abstract: The purpose of this paper is to determine Young's modulus and the shear modulus of some welded joints made with usual tubular steel by flexural vibration tests. This is the case of the type carbon steel plates S235 JR according to EN 10025, with a thickness of 3 mm welded with MIG/MAG welding process with R713 tubular wire with a diameter of 1.2 mm, using SelcoNeoMig 3500 equipment. The technological part is detailed: welding parameters used, advantages and disadvantages of tubular wires use, problems regarding ambient protection, punctual applications of welding procedures with tubular wire. Processing the obtained signal based on vibration response the elasticity modulus is determined and its value is then compared with the value of elasticity modulus obtained through tensile stress and also with the value obtained by theoretical way.

Abstract: An experiment gun mount system is used to clamp the small arms and replace gunner to conduct the automatic shooting in the shooting accuracy test. Because of the concomitant phenomena such as high shock and vibration when shooting, to study the vibration characteristics of the system, a modal analysis method was proposed and the experimental points, including the exciting points and the vibration pickup points, were determined on the basis of its geometric model. Based on the Fast Fourier Transform technique, the CRAS modal testing system was built. The modal experiment of the system was carried out by hammer blow method. The exciting signals, spectra of impacting prompt power, vibration acceleration and their frequency response functions were obtained. The first six order vibration modes, damping ratio and the corresponding vibration frequencies were obtained, which laid the foundation for dynamic response calculation and further optimization design of the system in the future.

Abstract: This paper introduces a combination of testing and finite element simulation for the abnormal vibration of a truck cab in specific speed. Vibration characteristics of the truck is tested. The factors that caused the abnormal vibration of the truck is found. The finite element model is established and the modal analysis is performed, the correctness of the test results is verified, and a reliable finite element model for the follow-up solution is provided. The abnormal vibration was caused by the frequencies of radial force variation which almost equal to the truck natural frequency under the vehicle velocities of 50km/h. The approach described in this paper can be applied to similar vibration problem diagnosis.

Abstract: t is presented a method for determining the mechanical characteristics based on the vibration response of the CMT (Cold Metal Transfer) joints from thin sheets of stainless steel joined with CuSi3 filler wire. The experimental results obtained by vibration testing will be compared with the theoretical results, and with those obtained by classical methods from stress-strain diagram. Technical details are given also for obtaining these joints (parameters, equipment specifications) indicating also their applicability.

Abstract: Applicability of the welded structures in different operating conditions requires experimental research developed in conditions previously imposed for each punctual application. There are analyzed in this case, in terms of vibration testing, some welded joints made with usual tubular steel wire. This is the case of the type carbon steel plates S235 JR according to EN 10025, with a thickness of 3 mm welded with MIG/MAG welding process with R713 tubular wire with a diameter of 1.2 mm, using SelcoNeoMig 3500 equipment. By processing the received signal based on the vibrations response to determine the elastic modulus of the welded structure, which will then be compared both with the modulus value obtained by tensile tests, and with the theoretical value obtained. The results thus obtained will be the basis of design, in optimal conditions of the welded structures regarding the appropriate behavior to the demands imposed.