Viscous inner and outer pressure forming method of thin-walled tube and its application

Abstract

Aiming at overcoming the difficulties in integral forming of thin-walled tubes with complex shapes, a novel forming method by inner and outer pressure through viscous was proposed. In this method, by dividing large deformation of the part into inner and outer pressure forming deformations, the limit deformation of tube part can be increased by several times. Meanwhile, the principle of viscous inner and outer pressure forming was provided, and key problems during the forming process such as reduction of the wall-thickness and instability wrinkling were analyzed. Thereby, the complex curved surface super-alloy GH3044 thin-walled tube with varying diameter ratio of 1.35 (the ratio between the maximum and minimum diameters of the part) can be integrally formed by this method. The experimental surface of the formed part is superior in quality and the wall-thickness distribution is uniform. The results show that the viscous inner and outer pressure forming can provide a new approach for integral forming of thin-walled tubes with complex shapes.

Keywords

thin-walled tube / inner and outer pressure forming / viscous medium / integral forming

References

[1] Elyasi M, Bakhshi-Jooybari M, Gorji A. Mechanism of Improvement of Die Corner Filling in a New Hydroforming Die for Stepped Tubes [J]. Materials and Design, 2009, 30: 3 824-3 830.

[2] Yuan SJ, Lang LH, Wang ZR. Progress in Research and Application of Tube Hydroforming [J]. Journal of Materials Processing Technology, 2000, 32: 60-63.

[3] Strano M, Jirathearanat S, Shr SG, et al. Virtual Process Development in Tube Hydroforming [J]. Journal of Materials Processing Technology, 2004, 146: 130-136.

[4] Shan DB, Kim Y, Lu Y, et al. Characteristics of Tee Tube Forming Deformation Zone Using Plastic Pressure Building Medium [J]. Metals and Materials, 2000, 6: 519-524.

[5] Lücke HU, Hartl C, Abbey T. Hydroforming [J]. Journal of Materials Processing Technology, 2005, 115: 87-89.

[6] Siegert K, Lopez P. Hydroforming at Tube with External High Pressure[C]. 1st International Conference on Hydroforming, Stuttgart, 1999 463-480.

[7] Prakash R, Singhal RP. Shear Spinning Technology for Manufacture of Long Thin Wall Tube of Small Bore [J]. Journal of Materials Processing Technology, 1995, 54: 186-192.

[8] Wang ZF, Piao FX, Wang ZY, et al. Electromagnetic Field Simulation and Crack Analysis of Electromagnetic Forming of Magnesium Alloy Tube [J]. J. of the Braz. Soc. of Mech. Sci. & Eng., 2011, 1: 41-44.

[9] Park YB, Kim HY, Oh SI. Design of Axial/Torque Joint Made by Electromagnetic Forming [J]. Thin-Walled Structures, 2005, 43: 826-844.

[10] Gao TJ, Wang ZJ, Gao HB. Integral Forming for Special-shaped Curved Surface Shell Parts of Turbofan Engine [J]. Journal of Propulsion Technology, 2007, 28: 437-440.

[11] Wang ZJ, Liu JG, Wang XY, et al. Viscous Pressure Forming (VPF): State-of-the-Art and Future Trends [J]. Journal of Materials Processing Technology, 2004, 151: 80-87.

[12] Singer W, Kaiser H, Singer X, et al. Hydroforming of Superconducting Tesla Cavities [J]. Journal of Metal Processing Technology, 2000, 87: 102-108.

[13] Liu J, Ahmetoglu M, Altan T. Evaluation of Sheet Metal Formability, Viscous Pressure Forming (VPF) Dome Test [J]. Journal of Materials Processing Technology, 2000, 98: 1-6.

[14] Wang ZJ, Wang XY, Wang ZR. Viscous Pressure Forming (VPF) of Corrugated Thin-walled Sheet Part with Small Radius [J]. Journal of Materials Processing Technology, 2004, 145: 345-351.