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Tong H.,Tianjin University | Zhao P.,Tianjin University | Huang C.,University of Alberta | Zhang H.,Tianjin University | And 2 more authors.
Desalination and Water Treatment

To meet the growing demand for potable water, desalinated water is becoming a significant component of the overall water supply. As a result, there is an increased need to understand how the addition of desalinated water within aging water distribution systems impacts water quality and the ability to deliver safe drinking water when unlined cast iron pipes and cement mortar-lined cast iron pipes are both present in the distribution systems. In this paper, we studied the relationship of turbidity, total iron content, and the effects of pH, alkalinity, and hardness on the dissolved silica. Then, we presented the mathematical and pilot-scale empirical development and quantification of three nonlinear regression models and used pH, alkalinity, total hardness, temperature, and hydraulic retention time as water quality variables. The dependent variables were the total iron concentration, the increase in turbidity, and the concentration of dissolved silica. Based on the three models, which use a genetic algorithm, an integrated solution for simultaneously minimizing the release of iron, the increase of turbidity, and the dissolved silica content was presented. This solution provides an economical and efficient method for water plants to identify specific water quality parameters that require adjustment to maintain an acceptable water quality. © 2014 Balaban Desalination Publications. All rights reserved. Source

Li X.,University of Science and Technology Beijing | Fan Y.,China Petroleum Pipeline Research Institute | Ma X.,McMaster University | Subramanian S.V.,McMaster University | Shang C.,University of Science and Technology Beijing
Materials and Design

The objective of the present study is to elucidate the impact of Martensite-Austenite (M-A) constituents formed at different intercritical temperatures on toughness. Gleeble thermal simulation technique has been used to produce different intercritically reheated coarse grained heat affected zone (ICCGHAZ) microstructures corresponding to different reheating temperatures between Ac1 and Ac3. The instrumental Charpy impact test results of dual pass thermal simulation showed that Charpy impact toughness improved with the increasing of second peak temperature. The fraction of M-A constituent was similar at each temperature. Near-connected coarse necklacing M-A constituents (2.4μm) formed at 760°C (near to Ac1) led to the worst toughness (42J) while those formed at 800°C and 840°C (near to Ac3) resulted in better toughness, respectively 80J and 105J. M-A constituents formed at 800°C were still coarse (2.2μm) but had larger interspace compared to 760°C. And those formed at 840°C were refined (1.9μm) and well dispersed by matrix. Notable difference in toughness values is attributed to the size and distribution of M-A constituents formed at different intercritical temperatures. It is possible to achieve better toughness if M-A constituents are well controlled: smaller in size and larger in interspacing. © 2014 Elsevier Ltd. Source

Liu Y.,China Petroleum Pipeline Research Institute | Liu Y.,National Engineering Laboratory for Pipeline Safety | Ma A.,Tian Jin SERI Machinery Equipment Co. | Feng B.,China Petroleum Pipeline Research Institute | Feng B.,National Engineering Laboratory for Pipeline Safety
Materials Science Forum

In this paper, the simulation heat affected zone (HAZ) continuous cooling transformation (SHCCT) curve of X90 pipeline steel was drew by using Gleeble 3500 simulator. The results show that the trend of hardening of the weld HAZ of X90 pipeline steel was moderate, and softening tendency was not significant. When cooling rate was between 1°C/s and 10°C/s, the microstructure of X90 pipeline steel weld HAZ were composed of granular bainite and lath bainite. The recommended welding heat input of X90 pipeline steel was between 21kJ/cm and 66.4kJ/cm, and the weld preheating temperature was controlled about 100°C. In conclusion, optimization control measures on the microstructure and properties of X90 pipeline steel weld HAZ are presented by above comprehensive analysis. © 2016 Trans Tech Publications, Switzerland. Source

Cheng M.,China Petroleum Pipeline Engineering Corporation | Zhang W.,China Petroleum Pipeline Engineering Corporation | Sun P.,China Petroleum Pipeline Research Institute | Huang L.,China Petroleum Pipeline Research Institute
ICPTT 2012: Better Pipeline Infrastructure for a Better Life - Proceedings of the International Conference on Pipelines and Trenchless Technology 2012

When MTBM is used to construct a tunnel in cohesive soil area, the main force need to resist is adhesive force generated by soil or clay around the machine, which can be reduced by the lubrication. In this case, the most commonly used lubrication is bentonite mud, which is injected through ports in the jacking head and filled outside of the pipes. In rock area, the formation is hard enough to support the pipes, if both entrance and exit are sealed well enough to prevent the lubrication lose, and also make sure the mud be injected continuously and around the pipe all the time which makes the pipes "float", frictions between pipes and rocks will be nearly zero under this "perfect" status. So we can conclude that in rock area, the lubrication system is not only to reduce the resistance force coming from the soil, but also to lower the frictional force coming from rocks. In some sedimentary rock areas, clean water might be the best lubrication. This theory has been successfully used and proved in different crossings of MTBM site in China's second West-East Gas pipeline project. © 2013 American Society of Civil Engineers. Source

Liu Q.,China Petroleum Pipeline Research Institute | Li J.,China Petroleum Pipeline Research Institute | Chen P.,Tianjin University
IET Conference Publications

The forgings is widely used in mechanical manufacturing industry. The online measurement with high-precision is very important for the quality control. In order to measure the large forgings' size, a system that using linear structured light source and CCD image sensor is developed. The system puts forward to test the deformation of the light plane when the light meets the surfaces of workpieces. By analyzing the laser curve image, it calculates the spacial conic and the parameters thought coordinates transition. The measuring principle and the building process of the system are described. To detect the structuredlighted- stripe vision sensor model, a new calibration method based on the combined target is proposed. The experiments demonstrate the high repeatability and accuracy of the system. The experimental results have proved that the repeatable accuracy is within 0.04mm and the measured relative error is less than 0.13%. Source

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