This paper described the work of welding process design for the " West-East" pipeline project, which is high pressure, large diameter and heavy wall thickness. According to the different geographical situation, clim...This paper described the work of welding process design for the " West-East" pipeline project, which is high pressure, large diameter and heavy wall thickness. According to the different geographical situation, climate, culture and the flexibility of the welding methods, this work recommended the semi-automatic process at the east and middle sections and automatic process at the west section of the pipeline project. The manual process is recommended on the tie-in joints and repairs. The double joint pipe and the 3 joint pipe are recommended at the water net place and some in-ditch welding place to reduce the welding volume. Also the special redesigned bevels are recommended for the automatic process and the semiautomatic process. Through all destructive tests, the results shows the welds are meet the requirements of related standards, specifications and design documents.展开更多
The weldabiUty of some material is analyzed with simple calculating program in this paper, and weldability testing data are shared through database system. The welding procedures are designed with help of expert syste...The weldabiUty of some material is analyzed with simple calculating program in this paper, and weldability testing data are shared through database system. The welding procedures are designed with help of expert systems, and the knowledge is shared among welding engineers. Not only the preparing progress of the welding documents is completed with database systems but also the complex decision on the necessity of the qualification test according to the present procedure qualification records (PQRs) and manufacture codes is made. Moreover, the artificial neural network (ANN) technique is proven to be one of the effective ways to predict mechanical properties of welded joints when there are enough tested data to train the models. Finally, the achievements in modeling microstructure of welded joints are introduced, especially in solid transformation and grain growth in both heat-affected zone (HAZ) and welded molten pool.展开更多
文摘This paper described the work of welding process design for the " West-East" pipeline project, which is high pressure, large diameter and heavy wall thickness. According to the different geographical situation, climate, culture and the flexibility of the welding methods, this work recommended the semi-automatic process at the east and middle sections and automatic process at the west section of the pipeline project. The manual process is recommended on the tie-in joints and repairs. The double joint pipe and the 3 joint pipe are recommended at the water net place and some in-ditch welding place to reduce the welding volume. Also the special redesigned bevels are recommended for the automatic process and the semiautomatic process. Through all destructive tests, the results shows the welds are meet the requirements of related standards, specifications and design documents.
基金Acknowledgements Financial support by the National Natural Science Foundation of China under Grant No. 50775112 is gratefully acknowledged.
文摘The weldabiUty of some material is analyzed with simple calculating program in this paper, and weldability testing data are shared through database system. The welding procedures are designed with help of expert systems, and the knowledge is shared among welding engineers. Not only the preparing progress of the welding documents is completed with database systems but also the complex decision on the necessity of the qualification test according to the present procedure qualification records (PQRs) and manufacture codes is made. Moreover, the artificial neural network (ANN) technique is proven to be one of the effective ways to predict mechanical properties of welded joints when there are enough tested data to train the models. Finally, the achievements in modeling microstructure of welded joints are introduced, especially in solid transformation and grain growth in both heat-affected zone (HAZ) and welded molten pool.