Jia F.,Nanjing Southeast University |
Xu F.,Nanjing University |
Xia Z.,Yancheng Institute of Technology |
Zhou H.,Nanjing Southeast University |
Zhang D.,CSR Nanjing Puzhen Co.
Journal of Mechanical Science and Technology | Year: 2016
The power of a metro vehicle is supplied by the pantograph on the vehicle roof. During pantograph lifting, the insulator set of the pantograph is prone to fracture caused by the impact load. In this work, a Single-arm pantograph–insulator system (SPIS) of metro vehicles was studied for the fatigue fracture of the insulator set induced by impact load. The basic structure of the SPIS was first introduced. The dynamic axial force test and fatigue and fracture damage experiments was then conducted on SPIS for both simulation experiment platform and real vehicles to analyze the causes of the insulator fracture. A method to improve the design structure of the back-end insulator set was proposed to resolve the problems of both the impact failure of the insulator steel core and the stress concentration on the interface between a steel core and an epoxy resin. The finite element analysis results indicated that the improved insulator set shows a much smaller stress concentration. Therefore, the improved insulator set has a greatly reduced fatigue damage subjected to shear effect, which validated the feasibility of the improved structure design. © 2016, The Korean Society of Mechanical Engineers and Springer-Verlag Berlin Heidelberg.
Xia N.,CSR Nanjing Puzhen Co. |
Zhu Z.,CSR Nanjing Puzhen Co. |
Chen H.,Southwest Jiaotong University
Advanced Materials Research | Year: 2013
6005A aluminum alloys were welded at different relative humidity conditions. The effects of relative humidity on the salt fog corrosion of the welding joints were researched. The results showed that the weight loss of the joints after 14 days corrosion was higher than that corroded after 7days, but the corrosion rate was lower. The corrosion rate first increased then declined with the increase of environmental humidity for the joints corroded for 7days. However, when the environmental humidity was 80%, corrosion rate achieved the maximum, when environment humidity was 70%, corrosion rate was the lowest. After corroded for 14 days, corrosion rate was the maximum when the environmental humidity was 50%, and it was the lowest when the environmental humidity was 90%. The tensile strength declined obviously after corrosion. © (2013) Trans Tech Publications, Switzerland.
Li B.,Southwest Jiaotong University |
Wu M.,CSR Nanjing Puzhen Co. |
Jin W.,CSR Nanjing Puzhen Co. |
Zhou Y.,Southwest Jiaotong University |
And 2 more authors.
Corrosion Science and Protection Technology | Year: 2014
The corrosion behavior of the pure Al clad alloy A7N01P-T4 and its welding joints for conventionally making high speed train was studied by means of neutral salt spray corrosion tests. The results showed that the corrosion of the welding line was the most serious, the heat affected zone next, and the base metal was most slight. The corrosion process originated in pits on the aluminum clad. Meanwhile both the density and dimension of the pits increased with time, they even connected with each other to form large ulcer-like area. Energy dispersive spectroscopy and infrared spectrum showed that the corrosion products of A7N01P-T4 consisted of three elements: O, Al and C. The measurement of polarization curves proved that the free corrosion potentials negatively shift and the corrosion currents increase following a serie: the base alloy with Al clad, the weld zone and the base alloy without Al clad, in other words, of which the corrosion resistance decreased in the same direction. It is believed that the Al clad may be beneficial to enhancement of the corrosion performance of the matrix and the heat affected zone of A7N01P-T4.
Li X.,CSR Nanjing Puzhen Co. |
Li C.,CSR Nanjing Puzhen Co. |
Zhu Z.,CSR Nanjing Puzhen Co. |
Xu F.,CSR Nanjing Puzhen Co.
Hanjie Xuebao/Transactions of the China Welding Institution | Year: 2014
It is a great challenge to control the welding deformation of aluminum alloy sheet because of its characteristics of both material and structure. This kind of deformation is a key problem of welding quality in the railway industry. In this paper, more attentions have paid to welding distortion of joints made of aluminum alloy sheet by MIG welding. Herein, numerical simulation was served as an effective tool for simulating welding deformation. Based on moving heat source model and sectional temperature function, the welding process of top slab of end wall with 2.2mm thickness was simulated. Results showed that range of error between the deformation values of simulation and actual measurement was within 20%, the morphology of the welding pool simulated was basically in agreement with the experimentally measured results. Backward deformation and simulated structure coincide well with the results of actual welding process, welding process optimization of top slab of end wall was carried out by controlling arm pressure and position, welding sequence and backward deformation method.
Li C.G.,CSR Nanjing Puzhen Co. |
Dai Z.C.,CSR Nanjing Puzhen Co. |
Yun Z.H.,CSR Nanjing Puzhen Co. |
Li D.F.,CSR Nanjing Puzhen Co. |
Cao X.H.,CSR Nanjing Puzhen Co.
Advanced Materials Research | Year: 2014
Using the Renka Cline algorithm provided by OriginPro8. 6 to fit the longitudinal residual stress through parts of the measurement value on the A7N01-T5 aluminum alloy butt welded joints compared with the whole measurement value. The result shows that the fitting value approximates the measurement value. The fitting value is reliable. So, Renka Cline algorithm is a reliable method to analyze the longitudinal residual stress on a plate region. © (2014) Trans Tech Publications, Switzerland.
Csr Nanjing Puzhen Co. | Date: 2012-07-17
The present invention relates to a flexible direct-drive bogie and implements a flexible frame by using a flexible cross beam, so as to make it easy for left and right side-frames to nod relatively to adapt to a larger twist of a track. As the frame is flexible, a primary suspension of the present invention is simplified to a thin layer of rubber pad, so that the production cost is reduced. Flexible drive devices enable flexible suspension of a permanent magnetic motor, and at the same time, can transmit torque, improve transmission efficiency, and reduce a weight of a transmission mechanism