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.

The disclosure relates to a method for controlling a stretch-reducing mill. Tube ends of stretched tubes are optimized by controlling one or more motors of the stretch-reducing mill. The method includes at least one outlet-side wall thickness measurement and an automatic adjustment of the value of a speed change of the motors to the tube wall thickness profile. The progression of the speed changes over time of individual or all motors is also automatically adjusted on the basis of the tube wall thickness measured values.

The disclosure relates to a method for controlling a stretch-reducing mill. Tube ends of stretched tubes are optimized by controlling one or more motors of the stretch-reducing mill. The method includes at least one outlet-side wall thickness measurement and an automatic adjustment of the value of a speed change of the motors to the tube wall thickness profile. The progression of the speed changes over time of individual or all motors is also automatically adjusted on the basis of the tube wall thickness measured values.

An apparatus for forming an oval shaped duct, as well as a round duct for all required sizes and thicknesses for an AC system, in one continuous operation where two driving rolls advance a flat metal sheet to at least one multi-positioning bending roll, where the at least one bending roll is moveable to a bending position for different curvatures and a non-bending position. The driving rolls advance the sheet through while the bending roll bends the sheet to form the curved sides, and the bending roll in the non-bending position form the flat sides of the oval shaped duct. A position sensor detects the position of the flat metal sheet in the rolls to control the location along the sheet where the bending roll is moved to either of the bending or non-bending positions while the driving rolls are stopped. An adhesive dispenser joins both ends of the sheet, resulting in a complete duct.

An apparatus for forming an oval shaped duct, as well as a round duct for all required sizes and thicknesses for an AC system, in one continuous operation where two driving rolls advance a flat metal sheet to at least one multi-positioning bending roll, where the at least one bending roll is moveable to a bending position for different curvatures and a non-bending position. The driving rolls advance the sheet through while the bending roll bends the sheet to form the curved sides, and the bending roll in the non-bending position form the flat sides of the oval shaped duct. A position sensor detects the position of the flat metal sheet in the rolls to control the location along the sheet where the bending roll is moved to either of the bending or non-bending positions while the driving rolls are stopped. An adhesive dispenser joins both ends of the sheet, resulting in a complete duct.

A rolling mill stand for rolling rod-shaped bodies, in particular tubular bodies, said stand comprising at least three rolls (10) mutually arranged to define a rolling pass line for said rod-shaped and/or tubular bodies, wherein at least one of said three rolls (10) is rigidly mounted on a roll holder shaft (20), freely fixed in turn in a rotational manner to said stand by means of a first hollow support (40) and a second hollow support (30) arranged on opposite sides of said at least one roll (10), respectively, wherein a first portion (21) and a second portion (22) of said roll holder shaft (20) are housed in said first hollow support (40) and in said second hollow support (30), respectively, where the constraint between at least said first hollow support and said first portion (21) of the roll holder shaft is of elastic type.

An apparatus and a process for forming an oval shaped duct, as well as a round duct for all required sizes and thicknesses for an AC system, in one continuous operation where two driving rolls advance a flat metal sheet to a multi-positioning bending roll, where the bending roll is moveable to a bending position for different curvatures and a non-bending position. The driving rolls advance the sheet through while the bending roll bends the sheet to form the curved sides, and the bending roll in the non-bending position form the flat sides of the oval shaped duct. A position sensor detects the position of the flat metal sheet in the rolls to control the location along the sheet where the bending roll is moved to either of the bending or non-bending positions while the driving rolls are stopped.

An apparatus and a process for forming an oval shaped duct, as well as a round duct for all required sizes and thicknesses for an AC system, in one continuous operation where two driving rolls advance a flat metal sheet to a multi-positioning bending roll, where the bending roll is moveable to a bending position for different curvatures and a non-bending position. The driving rolls advance the sheet through while the bending roll bends the sheet to form the curved sides, and the bending roll in the non-bending position form the flat sides of the oval shaped duct. A position sensor detects the position of the flat metal sheet in the rolls to control the location along the sheet where the bending roll is moved to either of the bending or non-bending positions while the driving rolls are stopped.

A method and an installation for continuously shaping longitudinally slotted pipes from a flat material minimizes or avoids markings in the material by evenly introducing into the roll stand the rolling forces of at least two rolls acting successively on the flat material and/or by allowing the two successively acting rolls to align freely relative to one another.

A method and an installation for continuously shaping longitudinally slotted pipes from a flat material minimizes or avoids markings in the material by evenly introducing into the roll stand the rolling forces of at least two rolls acting successively on the flat material and/or by allowing the two successively acting rolls to align freely relative to one another.