A method for manufacturing an electric resistance welded steel pipe having an identifiable seam portion. The method includes electric resistance welding a steel pipe, cutting an inner surface bead and an outer surface bead of the steel pipe in such a manner so as to cut: (i) a whole the outer surface bead and a part of the inner surface bead to leave an uncut portion in the inner surface bead, or (ii) a whole of the inner surface bead and a part of the outer surface bead to leave an uncut portion in the outer surface bead, coating the steel pipe with zinc phosphate, and cold drawing the steel pipe using a plug and a die to make the seam portion of the steel pipe identifiable.

This disclosure provides a tube shaping tool for a torque mechanism to modify a tube end. The tube shaping tool can include a cup and an internal assembly. The internal tube assembly can include a stem and an internal body. The stem can be received by the torque mechanism and transmit torque generated from the torque mechanism to the components of the tube shaping tool. The tube shaping tool can roll form the outside diameter of the tube end using standard bearings and a flange bearing attached to the internal body. The flange bearing can also include a flange that can provide facing of the tube end.

This disclosure provides a tube shaping tool for a torque mechanism to modify a tube end. The tube shaping tool can include a cup and an internal assembly. The internal tube assembly can include a stem and an internal body. The stem can be received by the torque mechanism and transmit torque generated from the torque mechanism to the components of the tube shaping tool. The tube shaping tool can roll form the outside diameter of the tube end using standard bearings and a flange bearing attached to the internal body. The flange bearing can also include a flange that can provide facing of the tube end.

A method for producing a steel material for line pipes which has a tensile strength of 570 MPa or more, a compressive strength of 440 MPa or more, and a thickness of 30 mm or more, the method including heating a steel having a specific composition to a temperature of 1000 C. to 1200 C.; performing hot rolling such that a cumulative rolling reduction ratio in a non-recrystallization temperature range is 60% or more, a cumulative rolling reduction ratio in a temperature range of (a rolling finish temperature +20 C.) or less is 50% or more, and a rolling finish temperature is the Ar.sub.3 transformation point or more and 790 C. or less; and subsequently performing accelerated cooling from a cooling start temperature of the Ar.sub.3 transformation point or more, at a cooling rate of 10 C./s or more, until the temperature of a surface of a steel plate reaches 300 C. to 500 C.

A lubrication ring for a mechanical expander (1) for sizing large pipes comprises a conventionally manufactured ring (12) made of steel, in particular construction steel. Fluid bores are provided in the ring (12). A part (13) of the lubrication ring (6) is manufactured by an additive manufacturing technology.

A method for producing a steel material for line pipes including heating a steel having a specific composition to a temperature of 1000 C. to 1200 C.; performing hot rolling such that a cumulative rolling reduction ratio in a non-recrystallization temperature range is 60% or more, a cumulative rolling reduction ratio in a temperature range of (a rolling finish temperature +20 C.) or less is 50% or more, and a rolling finish temperature is the Ar.sub.3 transformation point or more and 790 C. or less; subsequently performing accelerated cooling from a temperature of the Ar.sub.3 transformation point or more, at a cooling rate of 10 C./s or more, to a cooling stop temperature of 200 C. to 450 C.; and then performing reheating such that the temperature of a surface of the steel plate is 350 C. to 550 C. and the temperature of the center of the steel plate is less than 550 C.

There are provided an electric resistance welded steel pipe for producing a high strength hollow stabilizer excellent in fatigue resistance and a high strength hollow stabilizer. In an electric resistance welded steel pipe (5) for producing a hollow stabilizer, an internal weld bead cut portion (30) has a three-peak shape and a depth (H) of a trough portion (30a) of the three-peak shape is 0.3 mm or less and an angle () formed by a central portion in the circumferential direction of the trough portion (30a) and the top of right and left peak portions (30b, 30c) located on both the right and left sides of the trough portion (30a) is 160 or more and less than 180.

This disclosure provides a tube shaping tool for a torque mechanism to modify a tube end. The tube shaping tool can include a cup and an internal assembly. The internal tube assembly can include a stem and an internal body. The stem can be received by the torque mechanism and transmit torque generated from the torque mechanism to the components of the tube shaping tool. The tube shaping tool can roll form the outside diameter of the tube end using standard bearings and a flange bearing attached to the internal body. The flange bearing can also include a flange that can provide facing of the tube end.

This disclosure provides a tube shaping tool for a torque mechanism to modify a tube end. The tube shaping tool can include a cup and an internal assembly. The internal tube assembly can include a stem and an internal body. The stem can be received by the torque mechanism and transmit torque generated from the torque mechanism to the components of the tube shaping tool. The tube shaping tool can roll form the outside diameter of the tube end using standard bearings and a flange bearing attached to the internal body. The flange bearing can also include a flange that can provide facing of the tube end.

The present invention provides an integrated method for forming and performance control of NiAl alloy thin-walled tubular parts. A Ni/Al laminated foil tube is obtained after Ni foils and Al foils are alternately laminated and coiled; and the Ni/Al laminated foil tube is subjected to plastic forming, reaction synthesis and densification treatment in a gas bulging forming die to obtain a NiAl alloy thin-walled tubular part. The present invention solves the problem in the prior art that the preparation of an existing NiAl alloy sheet and the formation of the thin-walled tubular part from the sheet feature difficulty in material flow and structural performance control and a complicated process. Data of embodiments shows that the NiAl alloy thin-walled tubular parts obtained by using the method of the present invention has a high forming rate, high dimensional precision, uniform composition distribution, good tubular part compactness and no defects on the surface.