Numerical and experimental study on the inner diameter uniformity of hollow shafts in cross-wedge rolling with mandrel

Abstract Electromagnetic crimping is a solid state, high-speed, and high strain-rate joining process. Finite element analysis, as well as experimental study, was carried out on three types of field shapers, namely, tapered, taper-stepped, and stepped. In all three field shapers, the effective length, outer diameter, inner diameter, total length, and materials properties were constant. These field shapers were kept inside the same multi-turn solenoid coil for all the experiments. It was found that the taper-stepped field shaper results better regarding impact velocity, Lorentz force, temperature generation, less heating, and uniformity in crimping among the three types of field shapers.

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Modified Cross-Wedge Rolling for Creating Hollow Shafts

Procedia Manufacturing ◽

10.1016/j.promfg.2018.02.094 ◽

2018 ◽

Vol 21 ◽

pp. 53-59 ◽

Cited By ~ 6

Author(s):

Dirk Landgrebe ◽

Jürgen Steger ◽

Uwe Böhmichen ◽

Markus Bergmann

Keyword(s):

Cross Wedge Rolling ◽

Hollow Shafts

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Producing Hollow Shafts in a New Horizontal Mill by Novel Flat-Knifing Cross-Wedge Rolling With Single Guide

10.21203/rs.3.rs-569126/v1 ◽

2021 ◽

Author(s):

Longfei Lin ◽

Baoyu Wang ◽

Jinxia Shen ◽

Tao Liu

Keyword(s):

Numerical Simulations ◽

Experimental Tests ◽

Radial Force ◽

Transportation Industry ◽

Cross Wedge Rolling ◽

Forming Defect ◽

Engineering Significance ◽

Novel Method ◽

Hollow Shafts ◽

Rolling Stability

Abstract To meet the requirement of lightweight, there are increasing solid shafts being designed to be hollow in transportation industry. In this study, a novel method of flat-knifing cross-wedge rolling (FCWR) with single guide is proposed including a modified roller, a horizontal mill and a single-guide structure, and its key problems are studied by numerical simulations and experimental tests. A mathematical model of FCWR roller is established, which reveals the wedge length of rollers is effectively reduced by modifying knifing wedge from normalized roller. Further, a horizontal multifunctional mill is invented and constructed to carry out the FCWR experiment with single guide. According to the results from the numerical simulations and corresponding experiments, it is observed that the typical defects of hole expansion and knifing groove are absolutely avoided because the improved flat-knifing wedge produces a radial force to shrink the inner hole and avoid the deformation concentration of the outer surface during knifing stage. Moreover, the single guide rolling performed in the horizontal mill efficiently improve rolling stability because the workpiece is restricted into a smaller workspace. To the authors’ knowledge, all these integrated improvements of FCWR roller, single guide rolling and horizontal mill are innovative, which are of great engineering significance to manufacture hollow shafts on account of the advantages of avoiding forming defect, reducing roller diameter, improving rolling stability and simplifying mill structure.

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Effect of mandrel diameter on non-circularity of hollow shafts in cross wedge rolling

Procedia Engineering ◽

10.1016/j.proeng.2017.10.1011 ◽

2017 ◽

Vol 207 ◽

pp. 2376-2381 ◽

Cited By ~ 4

Author(s):

Xu Huang ◽

Baoyu Wang ◽

Jianguo Lin ◽

Chuanbao Zhu

Keyword(s):

Cross Wedge Rolling ◽

Mandrel Diameter ◽

Hollow Shafts

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The Experimental Study on Prestress Losses of Steel Stranded Wire in Non-Coherent Prestressed Concrete Silos

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.243-249.1331 ◽

2011 ◽

Vol 243-249 ◽

pp. 1331-1334

Author(s):

Hai Rong Huang ◽

Hao Zhang ◽

Lu Min Wang ◽

Qi Keng Xu ◽

Da Ying Zhang

Keyword(s):

Experimental Study ◽

Prestressed Concrete ◽

Prestress Losses ◽

Inner Diameter

In this paper, non-coherent prestressed steel stranded wire being introduced in one concrete silo model of 10m inner diameter is tensed at both ends. The prestress losses of wires are tested. Based on the tested result, the trend of prestress losses and prestressing wires strain is educed.

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An Experimental Study on the Cooling Effect of Die Casting Die Insert Cooling Devices

Heat Transfer, Volume 1 ◽

10.1115/imece2003-42160 ◽

2003 ◽

Author(s):

Feng Sun ◽

D. Schwam ◽

G.-X. Wang ◽

J. F. Wallace

Keyword(s):

Experimental Study ◽

Hot Spot ◽

Die Casting ◽

Relative Effectiveness ◽

Water Flow Rate ◽

Cooling Water ◽

Cooling Effect ◽

Cooling Channel ◽

Steel Cylinder ◽

Inner Diameter

Water is usually introduced into a die insert in die casting through a water line to reduce the temperature of the die insert and thus prevent its cracking. In many cases, a drilled waterline circuit is not possible due to confinement of the space. Bubblers or baffles then become typical water passage systems for die insert cooling. This paper presents an experimental study of the relative effectiveness of bubbler and baffle in die insert cooling. An internally channeled steel cylinder was designed as a die insert, with the blind channel drilled for water-cooling. Commercially available bubblers and baffles were inserted in the channel and water was introduced to cool the specimen when it was either heated in an air furnace or cyclically dipped into a molten aluminum bath. Thermocouples were mounted inside the wall of the cylinder to monitor the variation of the insert temperature under various cooling conditions. Experimental results indicate that both the bubbler and baffle can effectively lower the surface temperature of a die insert, with a bubbler being more suitable to cool a specific “hot spot” than a baffle. For a given cooling channel, within the experimental range, the bubbler with a smaller inner diameter has a better cooling effect to a “hot spot” than a bubbler with a larger inner diameter. Increasing the water flow rate always enhances the heat transfer between the cooling water and the sidewall of the cooling channel.

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