The Stress in a Helical Corrugated Tube under Axial Tension

Abstract

This paper deals with the stress in a helical corrugated shell subject to axial tension. In order to describe the form of such a shell, the corrdinate system (γ, θ, φ) is used, where coordinates γ, θ are those in cilindrical corrdinates (γ, θ, z), and φ is the length in z direction measured from the base helix. Because this is a skew system, an orthogonal system (λ, μ, n) is used together with it. The stress and strain are expressed referring to the system (λ, μ, n), and the position of the point is represented by the system (γ, θ, φ). Using these two systems, the problem treated now becomes a boundary value problem of ordinary differential equation. This equation is numerically integrated by electronic computer. The result shows that the weakest part of the helical corrugated tube is the trough, and the value of stress is close to that of the shell of rotational symmetry.