A cross-rolling mill for rolling a block over a mandrel forms a hollow block. It includes a plurality of working rollers, each of which exerts a substantially radially aligned rolling force onto the block. The working rollers are supported in a roll stand, and the gap between the working rollers and preferably also the alignment of the rolling axis of at least one of the working rollers relative to the block can be modified. Hydraulic actuators, preferably hydraulic capsules, are provided in order to modify the rolling gap and preferably also the alignment of the rolling axis of at least one of the working rollers relative to the block.

A cross-rolling mill for rolling a block over a mandrel forms a hollow block. It includes a plurality of working rollers, each of which exerts a substantially radially aligned rolling force onto the block. The working rollers are supported in a roll stand, and the gap between the working rollers and preferably also the alignment of the rolling axis of at least one of the working rollers relative to the block can be modified. Hydraulic actuators, preferably hydraulic capsules, are provided in order to modify the rolling gap and preferably also the alignment of the rolling axis of at least one of the working rollers relative to the block.

The technical field of metal plastic forming processes and equipment, and provides a device and method for forming shaft part by two-roller flexible skew rolling. The device comprises two skew rollers, a guiding plate, two guiding cylinders and an axial pushing device; the skew rollers can do same-direction rotation motion, radial feeding motion and tilt angle adjustment motion; the guiding plate is arranged between the two skew rollers and is used for limiting the radial movement of a blank; the two guiding cylinders are arranged on the two sides of the two skew rollers to limit swing of the blank; and the axial pushing device is arranged at one end of the blank and is used for applying axial pushing force to the blank, and the blank is rolled into a shaft part in a space defined by the skew rollers and the guiding plate. The method of the invention includes a radial compression forming process, a roller tilting forming process, a skew rolling diameter reduction forming process and a roller leveling forming process. The device and method for forming shaft part by two-roller flexible skew rolling have the advantages that forming equipment is simple, the tonnage is small, flexible production can be achieved, and core loose defects can be reduced and even avoided.

The technical field of metal plastic forming processes and equipment, and provides a device and method for forming shaft part by two-roller flexible skew rolling. The device comprises two skew rollers, a guiding plate, two guiding cylinders and an axial pushing device; the skew rollers can do same-direction rotation motion, radial feeding motion and tilt angle adjustment motion; the guiding plate is arranged between the two skew rollers and is used for limiting the radial movement of a blank; the two guiding cylinders are arranged on the two sides of the two skew rollers to limit swing of the blank; and the axial pushing device is arranged at one end of the blank and is used for applying axial pushing force to the blank, and the blank is rolled into a shaft part in a space defined by the skew rollers and the guiding plate. The method of the invention includes a radial compression forming process, a roller tilting forming process, a skew rolling diameter reduction forming process and a roller leveling forming process. The device and method for forming shaft part by two-roller flexible skew rolling have the advantages that forming equipment is simple, the tonnage is small, flexible production can be achieved, and core loose defects can be reduced and even avoided.

A cross-rolling unit and a method for setting the roll pass of a cross-rolling unit, having at least two rolls and a roll housing, in which at least one of the rolls is mounted such that its position can be adjusted in order to change the roll pass, allow the roll pass to be adjusted by means of a roll-positioning apparatus even during rolling, which roll-positioning apparatus is characterized by a housing-connected part and a roller-mill-connected part, which can be moved relative to the housing-connected part during rolling, which parts can be repositioned relative to each other, and/or which roll-positioning apparatus characterized by a drive which is dimensioned in such a way that rolling forces can be applied.

A cross-rolling unit and a method for setting the roll pass of a cross-rolling unit, having at least two rolls and a roll housing, in which at least one of the rolls is mounted such that its position can be adjusted in order to change the roll pass, allow the roll pass to be adjusted by means of a roll-positioning apparatus even during rolling, which roll-positioning apparatus is characterized by a housing-connected part and a roller-mill-connected part, which can be moved relative to the housing-connected part during rolling, which parts can be repositioned relative to each other, and/or which roll-positioning apparatus characterized by a drive which is dimensioned in such a way that rolling forces can be applied.

The seamless pipe in which a thin-walled portion in a pipe circumferential direction is formed in a pipe axial direction, in which a line segment formed by connecting one end and the other end of the thin-walled portion along a pipe surface with a shortest distance in a formation direction of the thin-walled portion is inclined at an angle α of 5.0° or more with respect to the pipe axial direction. It is preferable that one end and the other end of the thin-walled portion are set from a region in a pipe selected with a shorter length between a length of 1.0 m in the pipe axial direction and 90% of a length in the pipe axial direction where the thin-walled portion turns once in the pipe circumferential direction.

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.

Method of manufacturing zirconium alloy tubular products containing (wt. %): niobium—0.9-1.7; iron—0.04-0.10; oxygen—0.03-0.10; silicon—less than 0.02, carbon—less than 0.02, and zirconium—as the base of the alloy. This includes an ingot melting by multiple vacuum arc remelting, mechanical processing of the ingot, heating, hot working of the ingot, subsequent mechanical processing for the production of tubular billets, heat treatment of the tubular billets, application of a protective coating and heating to a hot pressing temperature, hot pressing, removal of the protective coating, multi-stage cold radial forging, vacuum thermal treatment, multiple cold rolling runs with a total deformation degree of 50-80-% per run and a tubular coefficient of Q=1.0-2.7 with intermediate vacuum thermal treatment after each cold rolling operation, and final vacuum thermal treatment of the resulting tubular products carried out at the final size with subsequent final finishing operations.