Advanced Materials Research Vols. 482-484

Abstract: This paper introduces the general temperature data processing procedure which stems from the thermocouple.On the base of summing up exsiting methods,the problem is detailed studied on how to select the special points of thermocouple.And a system is designed to collecting multichannel temperature data.By means of analysing the data,the mathematical model of thermocouple is founded. Proved by experiments, this method increases the temperature measurement precision and fits to actual request,which is wide rang with high pricise.

Abstract: The design of the third-order non-circular planetary gear is presented. In order to design the third-order non-circular planetary gear, the pitch of those gears is needed. Firstly theory and composition of the third-order non-circular planetary gear mechanism is introduced. Then according to the two conditions that the pitch should meet, the non-circular pitch formulas of the third-order non-circular planetary gear mechanism is given. Finally an application case of the center distance 3-4 type planetary gear mechanism was calculated by using the designed MATLAB program and created high-order elliptic curve. The design of the third-order non-circular planetary gear is achieved.

Abstract: In the system of the machine tool, the position error is directly affected by the thermal deformation of ball screw. Screw system is a complex thermal system, which is affected by the processing conditions, the processing cycle, the use of cooling fluid, and the surrounding environment. Due to non-linear and interaction of the thermal error, a RBF network thermal error model is proposed in the paper and the model is tested in XHFA2420 large machining center.

Abstract: A 3D elastic-plastic thermo-mechanical coupled finite element model of AZ31 Mg alloy profile during warm bending process was established. The effect of bending angle on the geometric accuracy of the profile was investigated. The results indicate that with increasing bending angle, the springback angles increase from 7.56° to 8.27°; the bending radii decrease from 90.15 mm to 90.01 mm; the cross-section distortion of the bent profile increases.

Abstract: An improved piezoresistive pressure sensor is designed for harsh environment application. The highlight of this design is that the Wheatstone bridge circuit is put in lower surface of pressure diaphragm and sealed in the vacuum pressure cavity. The bridge circuit is led out by embedded Al electrodes on bonding surface. ANSYS software has been used to analyze the stress distribution of the diaphragm. By using the MEMS technology, the pressure sensor with the dimension of 1.5mm×1.5mm×500µm is fabricated. The performance of piezoresistive pressure sensor, including output, sensitivity, and nonlinearity, are investigated. The test results show that sensitivity is 20mV/V-MPa and maximum nonlinearity is 2.73%, which meet the requirements for the modern industry.

Abstract: This study is focused on the temperature field distribution of the connecting rod. The temperature field and the time for reaching thermal equilibrium condition of the rod in a certain working environment are examined by means of finite element analysis (FEA). A verification experiment is implemented on the connecting rod. Comparison between our experiment and simulation shows that simulation values are in good agreement with experimental data. Findings from the study are supposed to provide a basis for reduction of the thermal deformation of rod as well as for improvement of the thermal characteristics and precision of high speed press.

Abstract: In order to select threshold of CT image of asphalt mixture for image segmentation more accurately, the perlite powder was added in asphalt mixture to increase the density contrast, three different mixture gradations in which added different levels of perlite powder were prepared and compacted in laboratory, the X-ray CT was used to scan the asphalt mixture specimen to obtain continuous CT images, the CT images were transformed to be histograms which formed double peak. Through comparing with the double peak situation of three mixture types, AC-13 has the best double peak situation, AK-13 and SMA-13 have similar feature of histogram. The results indicate that the addition levels of perlite powder influence the double peak situation significantly. This new approach is an effective way to identify aggregates, mastic and air voids exactly.

Abstract: Supply chain has become a leading role in this severely competitive market, while the research on supply chain performance has not been paid enough attention to improve overall operational abilities and effectiveness. Based on the view of an integrated supply chain, we develop a theoretical model of factors affecting supply chain performance from the points of material flow, commercial flow and information flow. It also describes the main procedure to finish this empirical research on this subject and explores hypothetical model building and measurement development. In this way, we pave the way for doing further empirical research on this subject.

Abstract: Currently, most of Chinese oil companies have getting in the later production period, the oil wells are processed frequently and the cost is increasing. In view of the higher problems existed popular in the oil fields such as multiple layers, big interlayer, the technology composited perforation and high energy gas fracturing has to construct with every layer alone, operate long time, cost high. The author puts forward the design research on the composite process of consecutive perforation-strong pulse fracturing for multiple oil layers and thick interlayer This paper introduces the basic design principle and technology method. The design is realized by using the technology of the perforation-symmetrical overpressure fracturing technology, the multi-pulse multistage fracturing, to efficiently guarantee the effect of perforating and pulse fracturing in every layer. The designed multistage detonating device makes the once completed construction technology used in the single well of the multiple oil layers with big interlayer come true. The field test application has gained good effects, greatly reduced the construction cost, and also promoted the application and generalization of the technology composited perforation and high energy gas fracturing.

Abstract: To reduce the impact of exhaust system hanger layout on the vehicle vibration performance and research the method about the reasonable layout of the hanger, forst established the FE model of an automotive exhaust system and fixed up hanger locations by modal analysis and load distribution by statics analysis. Then according to the displacement and force response to the engine’s torque loaded on powertrain’s mass centroid, adjusted hanger locations. At last, got the reasonable hanger location layout. The exhaust system hanger layout is used on a heavy truck and has the obvious effect.