Tool joints friction welded

The tool joints made by forging are heat treated by quenching and tempering. They are either friction welded or flash welded to the pipe body. For friction... 

Seamless steel pipe manufactured to API Specification 5D for Drill Pipe is used during the drilling operations. Available grades are E-75, X-95, G-105, and S-135 with specified minimum yield strengths (SMYS) of 75, 95, 105, and 135 ksi (517, 655, 724, 931 MPa), respectively. Drill pipe lengths are connected by tool joints, which involve a threaded pin and a box coupling. The couplings are friction welded to the pipe. 

Cylindrical pin hutt joint tools were used in the hrst friction stir lap welding (FSLW) attempts. These tools produced uplift adjacent to the friction stir zone and thinning of the upper sheet (Fig. 2.20). Interface uplift is produced by verhcal flow adjacent to the pin, which sharply moves the joint interface upward (typically on the advancing side of the tool). The angle of uplift can reach 90° and greatly reduces the fahgue resistance of the joint. Thinning of the... 

Threadless Tools. A simple lap welding tool consisting of a tool with two shoulders (Fig. 2.21) was developed by TWI and designated the Multistage tool (Ref 100). The first shoulder rested on the top surface of the overlapping plates. The second shoulder was located at the interface between the two lapped plates and was designed to disrupt the oxides at the lap joint interface. A variation of the Multistage tool was later used to friction stir weld 2.4 mm (0.09 in.)... 

A.P. Reynolds and W. Tang, Alloy, Tool Geometry, and Process Parameter Effects on Friction Stir Welding Energies and Resultant ESW Joint Properties, Friction Stir Welding and Processing, K.V. Jata, M.W. Mahoney, R.S. Mishra, S.L. Semi-atin, and D.P. Eield, Ed., TMS, 2001, p15-23... 

M. Ericsson and R. Sandstrbm, Fatigue of FSW Overlap Joints in Aluminum Welded with Different Tool Designs, Proceedings of the Fifth International Conference on Friction Stir Welding, Sept 14-16, 2004 (Metz, France), TWI, paper on CD... 

As a result of this process, a joint is produced in solid state. Because of various geometrical features of the tool, the material movement around the pin can be quite complex. During FSW process, the material undergoes intense plastic deformation at elevated temperature, resulting in generation of line and equiaxed recrystallized grains. The fine microstructure in friction-stir welds produces good mechanical properties of the joints, both static and dynamic. 

Friction stir welding uses the frictional heat to soften the material at the Joint area using a wear resistant rotating tool. 

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