Examination of working condition for reducing thickness variation in tube drawing with

The present research carried out a series of analyses using the finite element method (FEM). The analyses investigated the effect of working condition on thickness variation after drawing a tube with initial thickness distribution. As a result, it was notably revealed that application of dies with small half angle below 5 degrees was prominently effective for levelling the thickness variation. This effect was strengthen by employing tubes with thicker walls and larger diameters. Moreover, the mechanism of levelling the thickness variation was also examined. The small die angle affects the contact length at die approach, and the contact length at thinnest side becomes longer than that at the thickest side. The difference of the contact lengths equalizes the thicknesses of the thinnest and thickest sides. The analyses also predicted the thickness variation should almost be zero under an optimum condition

Effect of initial thickness deviation and reduction on longitudinal and cross-sectional precision after tube drawing using plug

In this research, 2D and 3D FEM models are composed for the clarification of the effect of initial thickness distribution on its distribution after drawing and the residual stresses. In the 2D FEM, the minimum bare element numberwas determined in terms on both residual stress precision and calculation time. Based on the results of 2D FEM, the element numberin3D FEM wasdetermined. Using the obtained 3D FEM, the effect of initial thickness distribution was clarified with the combination of thicknessreduction. It was revealed that light reduction in thickness in plug drawing sometimes lead to increase of thickness deviation, against intuitiveprediction based on tube drawing without plug.On the other hand, increase of thickness reduction resulted in decrease of thickness deviation. The mechanism of thickness change was also examined

Oncogenic FGFR1 mutation and amplification in common cellular origin in a composite tumor with neuroblastoma and pheochromocytoma

Neuroblastoma (NB) and pheochromocytoma (PCC) are derived from neural crest cells (NCCs); however, composite tumors with NB and PCC are rare, and their underlying molecular mechanisms remain unknown. To address this issue, we performed exome and transcriptome sequencing with formalin-fixed paraffin-embedded (FFPE) samples from the NB, PCC, and mixed lesions in a patient with a composite tumor. Whole-exome sequencing revealed that most mutations (80%) were shared by all samples, indicating that NB and PCC evolved from the same clone. Notably, all samples harbored both mutation and focal amplification in the FGFR1 oncogene, resulting in an extraordinarily high expression, likely to be the main driver of this tumor. Transcriptome sequencing revealed undifferentiated expression profiles for the NB lesions. Considering that a metastatic lesion was also composite, most likely, the primitive founding lesions should differentiate into both NB and PCC. This is the first reported case with composite-NB and PCC genetically proven to harbor an oncogenic FGFR1 alteration of a common cellular origin

Effect of initial thickness deviation and reduction on longitudinal and cross-sectional precision after tube drawing using plug

In this research, 2D and 3D FEM models are composed for the clarification of the effect of initial thickness distribution on its distribution after drawing and the residual stresses. In the 2D FEM, the minimum bare element numberwas determined in terms on both residual stress precision and calculation time. Based on the results of 2D FEM, the element numberin3D FEM wasdetermined. Using the obtained 3D FEM, the effect of initial thickness distribution was clarified with the combination of thicknessreduction. It was revealed that light reduction in thickness in plug drawing sometimes lead to increase of thickness deviation, against intuitiveprediction based on tube drawing without plug.On the other hand, increase of thickness reduction resulted in decrease of thickness deviation. The mechanism of thickness change was also examined