Research on Defect Detection of Fully-Wrapped Carbon Fiber Reinforced Hydrogen Storage Cylinder With an Aluminum Liner by Industrial Computed Tomography

Abstract

Currently, on-board storage cylinders of compressed hydrogen for land vehicles primarily use fully-wrapped carbon fiber reinforced cylinders with an aluminum liner. Due to the multi-layer structure of the hydrogen storage cylinder, nondestructive testing of the cylinder is facing great challenges and the nondestructive testing methods given in the standard are mainly internal and external surface testing by using visual inspection or an endoscope, causing that many internal defects cannot be identified. Industrial computed tomography is able to intuitively display three-dimensional information of the examined object, and thus this technology is expected to detect internal defects of the cylinders. In this study, the loading system of the cylinder, including limit plates, support blocks and support columns, was designed and manufactured. The industrial computed tomography test method with the use of a filter was established, and the delamination defects at the cylinder neck, shoulder, and cylindrical shell were systematically researched. It was found that the delamination defect width at the neck was the largest, followed by the defect width at the shoulder, and the defect width at the cylindrical shell was the smallest. In addition, the whole cylinder was detected by using spiral scan, demonstrating that this test method had the potential to be a common tool to monitor the cylinder defects.