This paper carries out the analysis of mechanics of a grip system of three-key-board hydraulic tongs developed for offshore oil pipe lines which has been successfully used in oil fields in China. The main improvement ...This paper carries out the analysis of mechanics of a grip system of three-key-board hydraulic tongs developed for offshore oil pipe lines which has been successfully used in oil fields in China. The main improvement of this system is that a lever frame structure is used in the structural design, which reduces greatly the stresses of the major components of the oil pipe tongs. Theoretical analysis and numerical calculation based on thirteen basic equations developed Show that the teeth board of the tongs is not easy to slip as frequently happens to other systems and is of higher reliability.展开更多
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 es...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 220-250 mm）.展开更多
文摘This paper carries out the analysis of mechanics of a grip system of three-key-board hydraulic tongs developed for offshore oil pipe lines which has been successfully used in oil fields in China. The main improvement of this system is that a lever frame structure is used in the structural design, which reduces greatly the stresses of the major components of the oil pipe tongs. Theoretical analysis and numerical calculation based on thirteen basic equations developed Show that the teeth board of the tongs is not easy to slip as frequently happens to other systems and is of higher reliability.
文摘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 220-250 mm）.
