| The curved pipe sensor is the key component of curved pipe flow-meter, the metrical precision based on the structural accuracy of curved pipe. For the sake of high metrical precision, searching after more appropriate methods of production and more reasonable manufacturing technique is the pursuing target of curved pipe flow-meter all the times.Based the cold extrusion bending without mandrel of curved pipe sensor as main context, this paper has provided information of the quality parameters influenced on the deformation quality, analyzed theoretically the status of force and strain and stress during the deformation process, provided the formula about deformation force, maximal thickness and minimum thickness after deformation.By FEM software Deform, the deformation quality under different structural parameters and the extruding force,the quality parameters at different t/D have been discussed. Many aspects have been analyzed comparatively, for example, the effective strain,the effective stress and velocity. It is found that theoretical consequence corresponds to simulated result, the deformed quality and law in theory and in simulation basically match each other, the reasonableness of part and die has been verified, provided the referenced basis for subsequence die design. It can conclude that the consequence is not ideal by cold extrusion bending without mandrel, it should manufacture with mandrel or adjust the cavity after deformation.By FEM software Deform, the numerical simulation of open die cold extrusion bending has been carried on too, and has drawn the conclusion that the instability happened in this condition.According to the experiment of curved pipe with open die cold extrusion, it is found that the instability to a greater or less extent happened. By comparing the experimental results and simulated ones, it is found that they both basically match each other. |
