Disclosed are differential temperature push bending method and device for tube with small bending radius, the device comprising: a push bending die, core, fillers and pushers, wherein the core and the fillers are both arranged in a bending chamber of the push bending die, an inlet and an outlet end of the push bending die are respectively provided with a front guiding sleeve and a rear guiding sleeve, the pusher in the front guiding sleeve abuts against a plurality of fillers, and the pusher in the rear guide sleeve abuts against the core. A heat rod is provided at an outer end of the bending chamber. The present disclosure adopts differential temperature type push bending, flow performance of the tube blank at the outer corner of the die can be improved, and the material can be timely fed to prevent excessive stretching and thinning of the outer material.

Disclosed are differential temperature push bending method and device for tube with small bending radius, the device comprising: a push bending die, core, fillers and pushers, wherein the core and the fillers are both arranged in a bending chamber of the push bending die, an inlet and an outlet end of the push bending die are respectively provided with a front guiding sleeve and a rear guiding sleeve, the pusher in the front guiding sleeve abuts against a plurality of fillers, and the pusher in the rear guide sleeve abuts against the core. A heat rod is provided at an outer end of the bending chamber. The present disclosure adopts differential temperature type push bending, flow performance of the tube blank at the outer corner of the die can be improved, and the material can be timely fed to prevent excessive stretching and thinning of the outer material.

The present disclosure discloses an apparatus and a method for forming a large-scale thin-walled ring shell by hot-press bending with internal gas pressure. The method comprises: welding a first head and a second head to the pipe; arranging a first electrode and a second electrode at the two ends of the pipe; charging compressed gas to the heated sealed pipe assembly; placing the sealed pipe assembly between the convex part of the first die and the concave part of the second die, controlling the temperatures of the first and second dies to perform press bending; increasing the gas pressure in the bent sealed pipe assembly, to attach the bent sealed pipe assembly to the die cavity profile; discharging the compressed gas, cutting the first head, second head and extra material to obtain a formed ring shell segment; welding formed ring shell segments to obtain a large-scale thin-walled ring shell.

The present disclosure discloses an apparatus and a method for forming a large-scale thin-walled ring shell by hot-press bending with internal gas pressure. The method comprises: welding a first head and a second head to the pipe; arranging a first electrode and a second electrode at the two ends of the pipe; charging compressed gas to the heated sealed pipe assembly; placing the sealed pipe assembly between the convex part of the first die and the concave part of the second die, controlling the temperatures of the first and second dies to perform press bending; increasing the gas pressure in the bent sealed pipe assembly, to attach the bent sealed pipe assembly to the die cavity profile; discharging the compressed gas, cutting the first head, second head and extra material to obtain a formed ring shell segment; welding formed ring shell segments to obtain a large-scale thin-walled ring shell.

The purpose of the present invention is to provide a method for producing a pipe material and to provide a mandrel with which resistance between a member to be processed and the mandrel during bending processing can be reduced and overall processing time can be shortened. The method for producing a pipe material includes: a step for inserting a mandrel, which is provided on the inside thereof with a flow path through which dry ice powder flows and spray holes at the tip thereof for spraying the dry ice powder, inside pipe material; a step for spraying the dry ice powder from the spray holes inside the pipe material; and a step for performing bending processing on the pipe material wherein the mandrel has been inserted.

The purpose of the present invention is to provide a method for producing a pipe material and to provide a mandrel with which resistance between a member to be processed and the mandrel during bending processing can be reduced and overall processing time can be shortened. The method for producing a pipe material includes: a step for inserting a mandrel, which is provided on the inside thereof with a flow path through which dry ice powder flows and spray holes at the tip thereof for spraying the dry ice powder, inside pipe material; a step for spraying the dry ice powder from the spray holes inside the pipe material; and a step for performing bending processing on the pipe material wherein the mandrel has been inserted.

A method and apparatus for bending a pipe to mitigate internal wrinkling, with particular benefit when bending a lined pipe upon spooling. Bending is performed continuously by advancing the pipe through a bending zone while an internal mandrel is held at the bending zone to resist wrinkling. In one variant, the mandrel comprises longitudinally-spaced pipe-engaging elements and a tensile link between the elements allows relative movement between the elements. A holdback connection on one of the elements applies hold-back force to that element to be transmitted to the other element via the tensile link. In another variant, the mandrel comprises an elongate pipe-engaging body with a hold-back connection at one end of the body. The body is flexible to bend with the pipe and is shaped to engage an inner surface of the pipe along most of the length of the body.

The present disclosure discloses an apparatus and a method for forming a large-scale thin-walled ring shell by hot-press bending with internal gas pressure. The method comprises: welding a first head and a second head to the pipe; arranging a first electrode and a second electrode at the two ends of the pipe; charging compressed gas to the heated sealed pipe assembly; placing the sealed pipe assembly between the convex part of the first die and the concave part of the second die, controlling the temperatures of the first and second dies to perform press bending; increasing the gas pressure in the bent sealed pipe assembly, to attach the bent sealed pipe assembly to the die cavity profile; discharging the compressed gas, cutting the first head, second head and extra material to obtain a formed ring shell segment; welding formed ring shell segments to obtain a large-scale thin-walled ring shell.

The present disclosure discloses an apparatus and a method for forming a large-scale thin-walled ring shell by hot-press bending with internal gas pressure. The method comprises: welding a first head and a second head to the pipe; arranging a first electrode and a second electrode at the two ends of the pipe; charging compressed gas to the heated sealed pipe assembly; placing the sealed pipe assembly between the convex part of the first die and the concave part of the second die, controlling the temperatures of the first and second dies to perform press bending; increasing the gas pressure in the bent sealed pipe assembly, to attach the bent sealed pipe assembly to the die cavity profile; discharging the compressed gas, cutting the first head, second head and extra material to obtain a formed ring shell segment; welding formed ring shell segments to obtain a large-scale thin-walled ring shell.

Disclosed are differential temperature push bending method and device for tube with small bending radius, the device comprising: a push bending die, core, fillers and pushers, wherein the core and the fillers are both arranged in a bending chamber of the push bending die, an inlet and an outlet end of the push bending die are respectively provided with a front guiding sleeve and a rear guiding sleeve, the pusher in the front guiding sleeve abuts against a plurality of fillers, and the pusher in the rear guide sleeve abuts against the core. A heat rod is provided at an outer end of the bending chamber. The present disclosure adopts differential temperature type push bending, flow performance of the tube blank at the outer corner of the die can be improved, and the material can be timely fed to prevent excessive stretching and thinning of the outer material.