Patent ID: 8245734

Claim:
A tubular blank for making a tubular structural component, the tubular blank defining a longitudinal axis along its length, the tubular blank comprising: a first end, an opposite second end and a main body extending between the first and second ends; the main body including a locally outwardly thickened first region longitudinally spaced from the first end and a locally inwardly thickened second region between the first region and the second end, the second region being longitudinally spaced from the second end, and a central region between the first and second regions; the first region having a first wall thickness, a first inner diameter and a first outer diameter, the difference between the first outer diameter and the first inner diameter defining the first wall thickness, and the second region having a second wall thickness, a second inner diameter and a second outer diameter, the difference between the second outer diameter and the second inner diameter defining the second wall thickness, the central region having a central outer diameter, a central inner diameter and a central wall thickness, wherein the central outer diameter is smaller than the first outer diameter and is substantially equal to the second outer diameter, the central inner diameter is substantially equal to the first inner diameter and is larger than the second inner diameter and the central wall thickness is smaller than the first and second wall thicknesses.