Abstract: In order to verify the detection ability of digital ray for the main defects of large volume steel liner-wound gas cylinders, and to give quantitative data of detection ability, this paper is aimed at the breakage and scratch of fiber layer which may occur during the use and manufacture of gas cylinders. Defects such as pores and liner corrosion, cracks, etc., and artificial defects such as series of grooves and flat bottom holes were made on the fiber layer and the inner liner to simulate the above-mentioned natural defects. And the artificial sample images were taken through the optimized transillumination parameters. The test results show that the digital ray detection method can detect the longitudinal grooving with a depth of 0.25 mm on the fiber layer and the circumferential groove with a depth of 0.5 mm, and also detect the longitudinal and circumferential grooves of the 0.25 mm depth on the inner liner. This proves that digital ray detection can be used for the initial detection of large-volume steel liner-wrapped cylinders, which provides strong support for safe use.

Key words: fiber composite, cylinder, X-ray digital imaging