A Bending Mechanism for Pipe Spinning Bending Progressive Forming Process

Abstract

The invention discloses a bending mechanism for a pipe spinning and bending incremental forming process. The bending mechanism comprises a support, a support frame, bending roller frames, bending rollers and pins, wherein the profile radii of the bending rollers are consistent with the radii of processed pipes; the bending rollers of different profile radii are located on the bending roller frames; the bending roller frames are located on the two sides of the support frame; the support frame is located above the support; and the pins are used for fixing the positions of the bending roller frames. The bending mechanism provided by the invention and targeted at the pipe spinning and bending incremental forming process is capable of being matched with the variable pipe diameter pipes in the forming process and ensuring that the action surface of the bending mechanism is perpendicular to the bending axis of the pipes, cross-section distortion caused by transverse shearing force of existingbending mechanisms to pipes is eliminated, and the bending forming quality and stability can be effectively improved.

Description

technical field [0001] The invention relates to the field of advanced manufacturing technology of metal bending components, in particular to a novel bending mechanism for a progressive forming process of pipe spinning and bending. Background technique [0002] With the development of aviation, aerospace, automobile, petrochemical and nuclear energy and other fields, higher requirements are put forward for the lightweight, functional diversification and reliability of the pipeline system. For load-bearing curved pipe fittings, optimizing the layout design of the diameter and wall thickness of the pipe according to the load-bearing requirements has become an important way to meet the lightweight requirements. In addition, the transmission pipeline system, especially the pipeline system that requires the control of flow changes, also has an important demand for variable diameter integrally curved pipe fittings. Therefore, there is an urgent need to research and develop advance...

AI Technical Summary

Problems solved by technology

The first is the ring-shaped bending mechanism reported in the international patent with the publication number WO2009043500A1. The mold of this bending mechanism is simple in form and easy to control the movement, but there are the following problems: (1) It cannot be applied to the bending and forming of pipes with variable diameters ; (2) When the bending radius is small, the curved back of the pipe is prone to flattening, resulting in cross-sectional distortion; (3) The contact between the bending mechanism and the pipe is sliding friction, which is easy to scratch the surface of the pipe

The bending roller has two profiles: V-shaped and arc-shaped. Among them, the V-shaped surface bending roller can match the bending of pipes with variable diameters, but it is in point contact with the pipe, which is prone to large cross-sectional distortion; the arc-shaped The surface bending roller is in line contact with the pipe, which effectively suppresses the distortion of the section, but it cannot match the bending of pipes with variable diameters

In addition, when forming with a single bending roller mechanism, it is impossible to ensure that the action surface of the bending mechanism is perpendicular to the bending axis of the pipe in real time, and the cross section of the pipe bend will be subjected to additional transverse shear force, resulting in an increase in the degree of distortion of the cross section of the bend, and it is difficult to guarantee the quality of the cross section

In summary, the existing two bending mechanisms cannot realize the overall high-quality forming of complex curved pipe fittings with the characteristics of variable pipe diameter, variable wall thickness, and multiple bending radii.

[0005] Therefore, the present invention proposes a new bending mechanism suitable for the progressive forming of pipe spinning and bending, which can effectively solve the existing problems of the existing bending mechanism that it cannot be applied to the bending of pipes with variable diameters, and cannot ensure that the active surface of the bending mechanism is in real time with the bending axis of the pipe. Cross-sectional distortion caused by verticality, surface scratches caused by sliding friction between the bending mechanism and the pipe, etc., to achieve overall high-quality forming of complex curved pipes with the characteristics of variable pipe diameter, variable wall thickness, and multiple bending radii

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