Study On The Technology Feasibility Of The Big Calibre And Thick Wall Pipe With The Centrifugal Blank-Forging Composite Process

There are mainly three methods for the traditional manufacture of the thick-wall pipe. The first is the centrifugal casting, the advantages of which are the simple manufacturing technics, the low cost, and the high material utilization ratio. But when manufacturing a big calibre and thick wall component which is usually used in the condition of high pressure and high temperature, the component's properties would not meet the requirement, and the Size of the inner surface of the casting couldn't also control easily; The second is the general Forging (piercing-drawing), which can manufacture the big calibre and thick wall pipe, and the component's properties can also meet the requirement. But in the forging formation, the plentiful energy consume and the long lead time reduce the productivity and increase the cost production in the producing process of the big calibre and thick wall pipe; The third is the process of roll thick-walled pipe, the advantages of which is the simple manufacturing technics, and the high material utilization ratio. But this method can only manufacture the seamed steel pipe but the seamless steel pipe, so this method can't be usually adopt when the pipe must be used in the condition of high pressure and high temperature.The Centrifugal Blank-Forging composite process are used in manufacturing one big calibre and thick-wall cast pipe mold-forging blank, and one boiler tube-forging blank. The centrifugal casting is used in manufacturing one cast pipe mold-casting blank. There is a dissection test for the cast pipe mold-casting blank and the cast pipe mold-forging blank, both of which are also analysed comparatively for macrostructure, microstructure, homogeneity of chemical components, and mechanical properties; There is also anther dissection test for boiler tube-forging blank, which is analysed for macrostructure and mechanical properties. Discussion the Technology feasibility of the big calibre and thick wall pipes with the Centrifugal Blank-Forging composite process through the analysis of the dissection test.The analysis of the dissection test of the cast pipe mold indicate that the homogeneity of chemical components is basically consistent., The macrostructure of the casting blank and the forging blank is all right, and the mechanical properties of the casting blank is higher than the forging blank's. The analysis of the dissection test of the boiler tube-forging blank also indicates that the macrostructure of the boiler tube-forging blank is all right, and the mechanical properties can also basically meet the requirement of the technical index.According to the analysis of the test, Through controlling the smelting steel quality and the steel purity straitly. The Centrifugal Blank-Forging composite process would be feasible in the producing process of the big calibre and thick wall pipe.