A device for handling mandrel rods in a rolling plant for rolling seamless tubes comprises an inserter. The inserter moves a mandrel rod in a rolling direction such that the mandrel rod, starting from an initial state, is pushed into a tube blank situated upstream of the mandrel rod. A retaining device has a fixing unit that is movable along the rolling line and is designed to temporarily hold the mandrel rod at an action point at a rear end of the mandrel rod and to carry out a working stroke. The mandrel rod can be inserted into the rolling mill in the rolling direction and pulled out of the rolling mill counter to the rolling direction by the retaining device. The retaining device is designed such that the starting position of the fixing unit lies between the two ends of the mandrel rod in the initial state.

A device for handling mandrel rods in a rolling plant for rolling seamless tubes comprises an inserter. The inserter moves a mandrel rod in a rolling direction such that the mandrel rod, starting from an initial state, is pushed into a tube blank situated upstream of the mandrel rod. A retaining device has a fixing unit that is movable along the rolling line and is designed to temporarily hold the mandrel rod at an action point at a rear end of the mandrel rod and to carry out a working stroke. The mandrel rod can be inserted into the rolling mill in the rolling direction and pulled out of the rolling mill counter to the rolling direction by the retaining device. The retaining device is designed such that the starting position of the fixing unit lies between the two ends of the mandrel rod in the initial state.

In a multi-roll table ring-rolling mill and method, a mandrel roll can be switched from a rolling state into a free-running state, when a predetermined ring diameter is reached, even if the roll gap minimum has not yet been reached, in order to improve the size accuracy of the rolled rings. A mandrel roll table rotating about a mandrel table axle is used, along with at least one main roll rotating about a main roll axle and first and second mandrel rolls that are mounted in the mandrel roll table, and a relief device to relieve at least the first mandrel roll of rolling forces. The main roll axle and the mandrel roll table axle are mounted in unchangeable manner and eccentric to one another, at least during the rolling process. The relief device acts independent of the main roll axle and the mandrel roll table axle are eccentric to one another.

In a multi-roll table ring-rolling mill and method, a mandrel roll can be switched from a rolling state into a free-running state, when a predetermined ring diameter is reached, even if the roll gap minimum has not yet been reached, in order to improve the size accuracy of the rolled rings. A mandrel roll table rotating about a mandrel table axle is used, along with at least one main roll rotating about a main roll axle and first and second mandrel rolls that are mounted in the mandrel roll table, and a relief device to relieve at least the first mandrel roll of rolling forces. The main roll axle and the mandrel roll table axle are mounted in unchangeable manner and eccentric to one another, at least during the rolling process. The relief device acts independent of the main roll axle and the mandrel roll table axle are eccentric to one another.

The present invention relates to a device for guiding a movable element, in particular a driving bar of a mandrel or a mandrel, in a rolling mill with mandrel. The device according to the invention comprises a support structure for the advancement of the movable element along an advancement direction. The device comprises a first slide and a second slide which are carried by said support structure and are slidable along a transverse direction which is substantially orthogonal to said advancement direction, in which each slide carries two abutment surfaces for guiding the movable element and in which each slide is movable along said transverse direction between at least a first operating position, upon reaching which said abutment surfaces are susceptible to coming into contact with a movable element of a first predefined diameter, and at least a second operating position, upon reaching which said abutment surfaces are susceptible to coming into contact with a movable element of a second predefined diameter. According to the invention, the device comprises actuating means which move the slides along the transverse direction between the operating positions and lock the slides themselves when one of said operating positions is reached.

The present invention relates to a device for guiding a movable element, in particular a driving bar of a mandrel or a mandrel, in a rolling mill with mandrel. The device according to the invention comprises a support structure for the advancement of the movable element along an advancement direction. The device comprises a first slide and a second slide which are carried by said support structure and are slidable along a transverse direction which is substantially orthogonal to said advancement direction, in which each slide carries two abutment surfaces for guiding the movable element and in which each slide is movable along said transverse direction between at least a first operating position, upon reaching which said abutment surfaces are susceptible to coming into contact with a movable element of a first predefined diameter, and at least a second operating position, upon reaching which said abutment surfaces are susceptible to coming into contact with a movable element of a second predefined diameter. According to the invention, the device comprises actuating means which move the slides along the transverse direction between the operating positions and lock the slides themselves when one of said operating positions is reached.

The present invention relates to a device for guiding a movable element, in particular a driving bar of a mandrel or a mandrel, in a rolling mill with mandrel. The device according to the invention comprises a support structure for the advancement of the movable element along an advancement direction. The device comprises a first slide and a second slide which are carried by said support structure and are slidable along a transverse direction which is substantially orthogonal to said advancement direction, in which each slide carries two abutment surfaces for guiding the movable element and in which each slide is movable along said transverse direction between at least a first operating position, upon reaching which said abutment surfaces are susceptible to coming into contact with a movable element of a first predefined diameter, and at least a second operating position, upon reaching which said abutment surfaces are susceptible to coming into contact with a movable element of a second predefined diameter. According to the invention, the device comprises actuating means which move the slides along the transverse direction between the operating positions and lock the slides themselves when one of said operating positions is reached.

The present invention relates to a device for guiding a movable element, in particular a driving bar of a mandrel or a mandrel, in a rolling mill with mandrel. The device according to the invention comprises a support structure for the advancement of the movable element along an advancement direction. The device comprises a first slide and a second slide which are carried by said support structure and are slidable along a transverse direction which is substantially orthogonal to said advancement direction, in which each slide carries two abutment surfaces for guiding the movable element and in which each slide is movable along said transverse direction between at least a first operating position, upon reaching which said abutment surfaces are susceptible to coming into contact with a movable element of a first predefined diameter, and at least a second operating position, upon reaching which said abutment surfaces are susceptible to coming into contact with a movable element of a second predefined diameter. According to the invention, the device comprises actuating means which move the slides along the transverse direction between the operating positions and lock the slides themselves when one of said operating positions is reached.

A rolling mill for rolling hollow or, in all cases, concave rod-shaped bodies, in particular tubes, in particular seamless tubes, said rolling mill comprising a rolling section (10) with a plurality of mill stands and/or rolling dies (11) arranged in succession to define a rolling axis Y, said rolling mill further comprising moving means for moving a mandrel (20) and a tubular blank (21) fitted onto an end portion (22) of said mandrel (20) along said rolling axis and through said mill stands or rolling dies (11) in succession; wherein said moving means are structured so as to move said mandrel (20) and said blank (21) along said rolling axis Y and through said mill stands or rolling dies (11) in succession by applying a traction on said mandrel.

A rolling mill for rolling hollow or, in all cases, concave rod-shaped bodies, in particular tubes, in particular seamless tubes, said rolling mill comprising a rolling section (10) with a plurality of mill stands and/or rolling dies (11) arranged in succession to define a rolling axis Y, said rolling mill further comprising moving means for moving a mandrel (20) and a tubular blank (21) fitted onto an end portion (22) of said mandrel (20) along said rolling axis and through said mill stands or rolling dies (11) in succession; wherein said moving means are structured so as to move said mandrel (20) and said blank (21) along said rolling axis Y and through said mill stands or rolling dies (11) in succession by applying a traction on said mandrel.