A kind of elastic mandrel for bending pipe

Abstract

An elastic core bar for a bent pipe comprises a core shaft used for supporting a straight pipe section and a plurality of core balls used for supporting a bent pipe section. The core shaft and the core balls are connected through an elastic body. The fixed end of the elastic body is fixed into the core shaft. The free end of the elastic body penetrates through the core balls in sequence, and a clamping positioning block limiting the displacement of the core balls is arranged at the end of the free end. The distance between two end faces of the core balls is defined as the thickness of the core balls. The thicknesses of the core balls are not consistent. The characteristics of a squillid body structure are used for reference, the spherical core balls are designed and connected through the elastic body, the wall of a pipe fitting can be more stably supported when small bent radius bending forming is carried out on the thin-wall pipe fitting, the friction force with the pipe fitting is smaller, and the quality of the bent pipe fitting is better.

Description

technical field [0001] The invention relates to an elastic mandrel for bending pipes. Background technique [0002] As a key lightweight component, thin-walled stainless steel elbow has the advantages of light weight, high strength, energy saving and environmental protection, and easy digitization, and has been widely used in aviation, aerospace and other high-tech fields. For example, the thin-walled stainless steel conduit used in the helicopter environmental control system should use pipe fittings with a diameter-to-thickness ratio of D / t>80 and elbows with a relative bending radius R / D<2. The stainless steel pipe fittings with large diameter-thickness ratio, thin wall, and small bending radius have obvious deformation strengthening during bending, and are easier to crack due to external tension and thinner wall thickness; small bending radii, larger deformation of the material, and easier Stretch cracking; pipe fittings with large diameter and weak circumferential...

AI Technical Summary

Problems solved by technology

[0005] In order to overcome the shortcoming that existing mandrels for bending pipes are easy to break, the present invention provides an elastic mandrel for bending pipes that can be bent freely and can be bent with a small bending radius and has good forming quality.

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