A method for manufacturing a strip having a variable thickness along its length, comprising the steps: an initial strip of constant thickness is provided; homogeneous cold rolling of the initial strip along its length in order to obtain an intermediate strip of constant thickness along the rolling direction; flexible cold rolling of the intermediate strip along its length in order to obtain a variable thickness strip, having, along its length, first areas with a first thickness (e+s) and second areas with a second thickness (e), less than the first thickness (e+s), continuous annealing of the strip. The plastic deformation ratio generated, after an optional intermediate recrystallization annealing, by the homogeneous cold rolling and the flexible cold rolling steps in the first areas is greater than or equal to 30%.

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.

According to the embodiment of the present disclosure, it provides a method of manufacturing a piston of a pump for brake system, the piston fabricated using a piercing process by press forming to have an inlet path communicating with a suction port through which oil is introduced.

According to the embodiment of the present disclosure, it provides a method of manufacturing a piston of a pump for brake system, the piston fabricated using a piercing process by press forming to have an inlet path communicating with a suction port through which oil is introduced.

A rolling rod configured as an inner tool in the production of seamless hollow bodies, such as seamless pipes. The rolling rod has a nitrided surface layer and may consist of a heat-resistant steel material having a chromium equivalent calculated by a formula, as well as has a minimum hardness, yield point and tensile strength. A seamlessly hot-rolled, metallic hollow body is produced by a stretch-forming procedure in a multiple-stand rolling mill via the rolling rod which is threaded into the hollow block. Prior to threading the rolling rod into the hollow block, the rolling rod is provided with a liquid lubricant and is subsequently dried. The rolling rod is threaded in with a clearance with respect to the inner diameter of the hollow block. Prior to threading-in the rod, the hollow block may have an average temperature of at least 1000 C., with the rod having a determined speed.

A rolling rod configured as an inner tool in the production of seamless hollow bodies, such as seamless pipes. The rolling rod has a nitrided surface layer and may consist of a heat-resistant steel material having a chromium equivalent calculated by a formula, as well as has a minimum hardness, yield point and tensile strength. A seamlessly hot-rolled, metallic hollow body is produced by a stretch-forming procedure in a multiple-stand rolling mill via the rolling rod which is threaded into the hollow block. Prior to threading the rolling rod into the hollow block, the rolling rod is provided with a liquid lubricant and is subsequently dried. The rolling rod is threaded in with a clearance with respect to the inner diameter of the hollow block. Prior to threading-in the rod, the hollow block may have an average temperature of at least 1000 C., with the rod having a determined speed.

A powder lubricant composition according to the present invention includes 65 parts by mass to 95 parts by mass of sodium borate, and 5 parts by mass to 35 parts by mass of cryolite. A method for manufacturing a seamless steel pipe according to the present invention includes adhering the above-described powder lubricant composition to a pipe inner surface of a work piece which is piercing rolled to have a tubular shape, and elongation rolling on the work piece after the adhering of the powder lubricant composition.

A powder lubricant composition according to the present invention includes 65 parts by mass to 95 parts by mass of sodium borate, and 5 parts by mass to 35 parts by mass of cryolite. A method for manufacturing a seamless steel pipe according to the present invention includes adhering the above-described powder lubricant composition to a pipe inner surface of a work piece which is piercing rolled to have a tubular shape, and elongation rolling on the work piece after the adhering of the powder lubricant composition.

Method for forming a collar in a muffler shell including: providing a muffler shell made of a metal sheet and forming a muffler housing, the muffler shell having an exhaust gas opening, providing a collar forming head having a rotational axis and at least two movable expanders, introducing a collar forming head into a muffler housing, moving the expanders of the collar forming head introduced into the muffler shell radially away from the rotational axis of the collar forming head from a retracted position to an expanded position rotating the collar forming head around the of the collar forming head, bringing the rotating expanded collar forming head in contact with the metal sheet forming an outwardly projecting collar around the exhaust gas opening by flaring the edge of the metal sheet.

Method for forming a collar in a muffler shell including: providing a muffler shell made of a metal sheet and forming a muffler housing, the muffler shell having an exhaust gas opening, providing a collar forming head having a rotational axis and at least two movable expanders, introducing a collar forming head into a muffler housing, moving the expanders of the collar forming head introduced into the muffler shell radially away from the rotational axis of the collar forming head from a retracted position to an expanded position rotating the collar forming head around the of the collar forming head, bringing the rotating expanded collar forming head in contact with the metal sheet forming an outwardly projecting collar around the exhaust gas opening by flaring the edge of the metal sheet.