The thesis is mainly contained Large-scale vertical heat exchanger manufacturing.It can be divided into three parts:Bundle machining and assemble;shell forming and machining,main weld weling and heat treating,and fina...The thesis is mainly contained Large-scale vertical heat exchanger manufacturing.It can be divided into three parts:Bundle machining and assemble;shell forming and machining,main weld weling and heat treating,and finally the requirement of drawing and specification can be reached.展开更多
This paper presents the research on the whole body restoration of over-service-time reforming reactors from the experiment study to the development of normalizing procedure.It is found that parts of alloy element in s...This paper presents the research on the whole body restoration of over-service-time reforming reactors from the experiment study to the development of normalizing procedure.It is found that parts of alloy element in solid solution transform to carbide, and carbide phase transformation occurs forming carbide precipitation concentrated at grain boundaries. As a result,the material toughness becomes worse seriously and the whole unit can not be run normally.Through the study of specimens,it is found that the best way to repair it is to use a special heat treatment procedure i.e. normalization under spray type cooling.A special spray cooling unit was designed for this purpose. The test-plate examination results prove that material physical properties have been improved after normalizing for the whole body reactor under spray type cooking. Through the assessment, the reactor can be used again.展开更多
文摘The thesis is mainly contained Large-scale vertical heat exchanger manufacturing.It can be divided into three parts:Bundle machining and assemble;shell forming and machining,main weld weling and heat treating,and finally the requirement of drawing and specification can be reached.
文摘This paper presents the research on the whole body restoration of over-service-time reforming reactors from the experiment study to the development of normalizing procedure.It is found that parts of alloy element in solid solution transform to carbide, and carbide phase transformation occurs forming carbide precipitation concentrated at grain boundaries. As a result,the material toughness becomes worse seriously and the whole unit can not be run normally.Through the study of specimens,it is found that the best way to repair it is to use a special heat treatment procedure i.e. normalization under spray type cooling.A special spray cooling unit was designed for this purpose. The test-plate examination results prove that material physical properties have been improved after normalizing for the whole body reactor under spray type cooking. Through the assessment, the reactor can be used again.
