High-pressure assemblies used in the oil and gas industry are usually pressure tested in hydro and gas pits. Pressure testing is critical in qualifying new components. Test pressures can be as high as 30 ksi or more. The high pressure water or gas used in testing can store large amounts of energy. Any component or part subjected to this pressure will experience high stresses. If any part of the assembly fails during the testing process, the stored energy of the high-pressure test media in the system can cause the failed part to be ejected at a very high velocity, leading to potential safety issues. Therefore it is crucial to design the reinforced concrete wall of the test pit appropriately to contain the ejected part and prevent or minimize associated damage.
This report presents methods to determine the concrete perforation thickness and subsequently, calculate the required test pit wall thickness for stopping a projectile. Since the projectile velocity is a function of test pressure, volume of the pressurized vessel (tested equipment), projectile plug geometry, vessel material, and the pressurized fluid, analyses will include all of these parameters. The test assembly and the ejected part will be simplified into a vessel and a plug in order to make quantitative assessments of the concrete pit wall penetration. Results from the analyses are expected to provide guidance on the concrete wall thickness for designing a safe, high-pressure test pit. The projectile velocities predicted analytically will be compared with those predicted by CFD analyses. Additionally, the analytical prediction of concrete perforation will be verified by running an explicit FE analysis of the concrete impact using LS-DYNA.
