Acta Metallurgica Sinica (English Letters) ›› 2010, Vol. 23 ›› Issue (1): 72-80.DOI: 10.11890/1006-7191-101-72

• Research paper • Previous Articles    

Forming process and numerical simulation of making upset on oil drill pipe

Huaping TANG1,2, Changqian HAO1, Yongzheng JIANG1, Lei DU1   

  1. 1. School of Mechanical and Electrical Engineering, Central South University, Changsha 410083, China
    2. School of Mechanical Engineering, Nantong University, Nantong 226007, China
  • Received:2009-08-12 Revised:2009-12-06 Online:2010-02-25 Published:2010-02-09
  • Contact: Huaping TANG

Abstract:

The flow stress behavior of grade G-105 steel (API  standard) for oil drill pipe in hot compressive deformation was  studied by isothermal compression tests on Gleeble-1500  thermal-mechanical machine. Referring to established empirical  formulas, the constitutive equation of the flow stress for G-105  steel was obtained. For the grade G-105 oil drill pipe  (φ114.3×10.92 mm), through proper design of the die and  applying suitable process parameters, and using coupled rigid  viscoplastic thermo-mechanical finite element method, the forming  process of making upset on oil drill pipe was numerically simulated.  The simulation results show that the internal transition section of  the oil drill pipe is not only continuous and smooth but also long  (up to about 220-250mm).

Key words: Oil drill pipe, Constitutive equation, Endupsetting, Numerical simulation