Ultrasonic Test Standards for Pressurized Gas Cylinders

Tonne Tank

Each year, PH Tool makes dozens of reference standards for ultrasonic testing (UT) of pressurized gas cylinders. Ultrasound is a great alternative to hydrostatic testing for cylinder recertification, allowing accurate measurement of wall thickness over the full length of the sidewall. UT can also pick up on other flaws like cracks, pits, gouges, corrosion and more that would not be found during a standard hydrostatic test. We are proud to provide reference standards to major OEMs who develop cylinder inspection systems, as well as specialty gas companies that have a need to inspect large quantities of cylinders.

Inside CylinderThe team at PH Tool are experts in manufacturing gas cylinder test standards to meet both DOT (Department of Transportation) and ISO testing requirements. We have worked on cylinders of every size; from "micro” cylinders of only a few inches in diameter all the way up to massive "Tonne Tanks” over 20” in diameter and several feet long. We can handle it all!

Cylinder Colors2Cylinders are provided to us by the end user, and the top of the cylinder is removed so that we can gain access to the internal surfaces. Each cylinder reference standard gets a series of EDM Notches, Flat-bottom Holes (FBH,) and rectangular wall-thinning pads machined into them to act as calibration targets for a UT inspection system. After the artificial defects are made in the cylinder, it can be re-capped by one of several methods. The original cylinder top can be welded back on, or we can install a flat welded cap instead. Some customers even opt to install a removable pipe plug in the open end. The pipe plug option affords the ability to easily open and reinspect the cylinder periodically to ensure the machined features have not degraded due to corrosion or wear over time.

Cylinder IsoWe work mostly on aluminum and steel cylinders, but have worked on specialty materials as well. Aluminum standards can be anodized to protect the surfaces, and steel standards can be nickel-plated in our in-house plating line to improve longevity and corrosion-resistance. Both of these coating options add only a tiny amount of thickness to the wall of the
cylinder, which does not affect thickness readings during testing.


Contact PH Tool Sales today to get started on your next gas cylinder inspection project!