Abstract: A method for making a riser component includes: positioning a coupler adjacent and end of a tube such that a region of the coupler forms an interface with the tube's end, wherein the region includes a material (in some embodiments an aluminum alloy), and the tube's end includes a groove and another material (in some embodiments a steel alloy) that is different than the region's material; heating the region of the coupler to increase the region's malleability; and exerting pressure on the region of the coupler to plastically deform the region to insert some of the region's material into the groove in the tube's end. By fixing the coupler to the tube in this manner, the coupler may be strongly secured to the tube, and thus able to withstand high, dynamic loads frequently experienced in service. Also, the material of the coupler may be different than the material of the tube, and thus the material of the coupler may be lighter than the material of the tube.

Abstract: A method for making a riser component includes: positioning a coupler adjacent and end of a tube such that a region of the coupler forms an interface with the tube's end, wherein the region includes a material (in some embodiments an aluminum alloy), and the tube's end includes a groove and another material (in some embodiments a steel alloy) that is different than the region's material; heating the region of the coupler to increase the region's malleability; and exerting pressure on the region of the coupler to plastically deform the region to insert some of the region's material into the groove in the tube's end. By fixing the coupler to the tube in this manner, the coupler may be strongly secured to the tube, and thus able to withstand high, dynamic loads frequently experienced in service. Also, the material of the coupler may be different than the material of the tube, and thus the material of the coupler may be lighter than the material of the tube.

Abstract: The present invention provides a tool for forming a friction stir weld joint in a workpiece. According to one embodiment, the tool includes a rotatable pin having first and second ends and defining a stirring portion therebetween structured to frictionally engage the workpiece so as to at least partially form the friction stir weld joint. The tool includes a rotatable first shoulder defining an aperture therethrough structured to slidably receive the first end of the pin. The tool also includes a second shoulder defining an aperture structured to receive the second end of the pin such that the pin extends between the first and second shoulders and such that the second shoulder is in rotatable communication with the pin. The first shoulder is structured to rotate independently of the pin and the second shoulder.

Abstract: The present invention provides a tool for forming a friction stir weld joint in a workpiece. According to one embodiment, the tool includes a rotatable pin having first and second ends and defining a stirring portion therebetween structured to frictionally engage the workpiece so as to at least partially form the friction stir weld joint. The tool includes a rotatable first shoulder defining an aperture therethrough structured to slidably receive the first end of the pin. The tool also includes a second shoulder defining an aperture structured to receive the second end of the pin such that the pin extends between the first and second shoulders and such that the second shoulder is in rotatable communication with the pin. The first shoulder is structured to rotate independently of the pin and the second shoulder.

Abstract: The present invention provides a tool for forming a friction stir weld joint in a workpiece. According to one embodiment, the tool includes a rotatable pin having first and second ends and defining a stirring portion therebetween structured to frictionally engage the workpiece so as to at least partially form the friction stir weld joint. The tool includes a rotatable first shoulder defining an aperture therethrough structured to slidably receive the first end of the pin. The tool also includes a second shoulder defining an aperture structured to receive the second end of the pin such that the pin extends between the first and second shoulders and such that the second shoulder is in rotatable communication with the pin. The first shoulder is structured to rotate independently of the pin and the second shoulder.

Abstract: A method for superplastically forming a preform to manufacture a structural assembly with a contoured configuration is provided. The preform includes first and second structural members in a stacked configuration, with at least one additional peripheral member abutting the stack and joined thereto by a friction welded butt joint. In some cases, the preform defines dissimilar forming characteristics throughout, such as variations in material or thickness according to the amount of superplastic forming to be performed in each portion of the preform.

Abstract: A method for superplastically forming a preform to manufacture a structural assembly with a contoured configuration is provided. The preform includes first and second structural members in a stacked configuration, with at least one additional peripheral member abutting the stack and joined thereto by a friction welded butt joint. In some cases, the preform defines dissimilar forming characteristics throughout, such as variations in material or thickness according to the amount of superplastic forming to be performed in each portion of the preform.

Abstract: The present invention provides a tool for forming a friction stir weld joint in a workpiece. According to one embodiment, the tool includes a rotatable pin having first and second ends and defining a stirring portion therebetween structured to frictionally engage the workpiece so as to at least partially form the friction stir weld joint. The tool includes a rotatable first shoulder defining an aperture therethrough structured to slidably receive the first end of the pin. The tool also includes a second shoulder defining an aperture structured to receive the second end of the pin such that the pin extends between the first and second shoulders and such that the second shoulder is in rotatable communication with the pin. The first shoulder is structured to rotate independently of the pin and the second shoulder.

Abstract: The present invention provides a tool for forming a friction stir weld joint in a workpiece. According to one embodiment, the tool includes a rotatable pin having first and second ends and defining a stirring portion therebetween structured to frictionally engage the workpiece so as to at least partially form the friction stir weld joint. The tool includes a rotatable first shoulder defining an aperture therethrough structured to slidably receive the first end of the pin. The tool also includes a second shoulder defining an aperture structured to receive the second end of the pin such that the pin extends between the first and second shoulders and such that the second shoulder is in rotatable communication with the pin. The first shoulder is structured to rotate independently of the pin and the second shoulder.

Abstract: The present invention provides a tool for forming a friction stir weld joint in a workpiece. According to one embodiment, the tool includes a rotatable pin having first and second ends and defining a stirring portion therebetween structured to frictionally engage the workpiece so as to at least partially form the friction stir weld joint. The tool includes a rotatable first shoulder defining an aperture therethrough structured to slidably receive the first end of the pin. The tool also includes a second shoulder defining an aperture structured to receive the second end of the pin such that the pin extends between the first and second shoulders and such that the second shoulder is in rotatable communication with the pin. The first shoulder is structured to rotate independently of the pin and the second shoulder.

Abstract: The present invention provides a tool for forming a friction stir weld joint in a workpiece. According to one embodiment, the tool includes a rotatable pin having first and second ends and defining a stirring portion therebetween structured to frictionally engage the workpiece so as to at least partially form the friction stir weld joint. The tool includes a rotatable first shoulder defining an aperture therethrough structured to slidably receive the first end of the pin. The tool also includes a second shoulder defining an aperture structured to receive the second end of the pin such that the pin extends between the first and second shoulders and such that the second shoulder is in rotatable communication with the pin. The first shoulder is structured to rotate independently of the pin and the second shoulder.