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This article presents a new integrated geometric model that takes worktable as reference for five-axis machine tools. It could simplify the description of different machine kinetic structures and uniform the measurement coordinate system and machining coordinate system. Based on this model, a new method of measuring geometric errors with conventional instruments is proposed. It could break through some existing limitations, such as special instrument, specific machine kinetic structures, or errors incompletion. In addition, some deviation errors in measuring process could be eliminated to improve accuracy further. Finally, a series of experiments are conducted on a five-axis machine tool with rotary worktable and tilting head. The results show that the error model and measuring method are effective and applicable.

The narrow face of continuous casting mold is the first impact region of the jet from the submerged entry nozzle (SEN), and against the characteristic a new pattern of electromagnetic brake device is proposed, which is called Vertical Electromagnetic Brake (V-EMBr) and its magnetic poles can cover the free surface and the frontier region of solidified shell. The effect laws of magnetic flux density, casting speed and the submergence depth of the SEN on flow field in mold with V-EMBr are investigated by numerical simulation method. The results show that with the magnetic flux density increasing, inhibitory effect of electromagnetic force on molten steel from SEN is increased gradually, impact strength of molten steel stream on narrow face is weakened gradually, the vortex center of lower recirculation zone is moved up gradually and the flow velocity of free surface is decreased gradually. These can reduce the fluctuations of free surface and chance of slag effectively, suppress impinging depth of molten steel in lower recirculation zone and float air bubbles and inclusions beneficially. In addition, the V-EMBr technology can also be applied to different casting speed and different submergence depth of the SEN in continuous casting process. The significantly metallurgical effects and flexibility of application range which are generated by V-EMBr is in line with the original intention of the V-EMBr design.

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