Asset Integrity of Gas Storage Sphere Legs Using Advanced Technologies

The inspection of the steel legs that hold up gas storage spheres has been difficult because of the thickness of cement that is applied to the legs to make them "fireproof". The cement contains steel studs that are welded to the legs and wire mesh that may vary in mesh size, all of which complicate the inspection possibilities. A new, low frequency AC scanning technique has been developed which can detect corrosion under fireproofing (CUF). The technique and its industry-supported development is described.

Learning gamma-ray scanning technique through an educational simulation rig

Gamma-ray scanning is non-destructive testing (NDT) technique to inspect problems in distillation columns of industrial plant. In order to familiarize with the problems’ identification and data interpretation, an attempt has been made by constructing an educational rig for simulation of gamma-ray scanning technique in a laboratory scale. The rig is made of cylindrical transparent acrylic material with a diameter and a height of 0.3 m and 2.4 m, respectively. The rig consists of artificial trays and packed bed structures designed in such a way that it represents a duplicate of the distillation unit but in a miniature size. The rig is also equipped with a submerged water pump and water tank which both are located at the bottom part of the rig. Water from the tank are circulated by a water pump through a pvc tube to a distributor at the upper part of the rig. In the rig, water is flowing downward gravitically for passing through packed bed and trays structures until terminated at the tank. The gamma-ray scanning experiment was carried out by moving the radiation detector and Cs-37 gamma-ray source simultaneously from top to bottom for every 5 cm moving step. Artificial problems such as flooding, tray positions, collapsed trays are clearly identified. The lesson learned from this experiment concludes that simulation of gamma ray scanning is very suitable for troubleshooting and diagnosing malfunctions of the internal structure of the distillation column.

A Lung Ultrasound Scanning Technique for Children and Adults in Low-Resource Settings: Preliminary Experiences in Sub-Saharan Africa

Lung ultrasound is increasingly used as a diagnostic tool for pulmonary pathologies by nonspecialist clinicians in resource-limited settings where chest X-ray may not be readily available. However, the optimal technique for lung ultrasound in these settings is not yet clearly defined. We describe here our experience of implementing a standardized, focused six-zone, 12-view lung ultrasound scanning technique with a high-frequency probe in both adults and children in a resource-limited setting in sub-Saharan Africa. Our experience suggests that this may be a feasible technique to rapidly introduce lung ultrasound to new learners that can be adapted to emergency or outbreak settings. However, research is needed to determine how this technique compares with clinical examination and other available tests for the diagnosis of pathology commonly encountered in resource-limited settings.

Comparison of digital scanning and conventional impression taking for implant-supported prostheses

The effect of discrepancies between digital scans and conventional impressions on the clinical performance of a permanent restoration has not been fully understood.Thirty patients received conventional impressions and digital scans of a single implant restoration. Two crowns were made for the same implant using both methods. The time taken for each procedure was recorded. After analyzing the accuracy and effectiveness of both crowns, the best one was placed. A questionnaire was conducted to assess the preferences and comfort when using crowns made by one method or another.The total time for the traditional impression technique was 15 minutes, while the time for the digital scanning technique was significantly less – 10 minutes.The preparation time, including the disinfection of the silicone impressions, their transportation to the laboratory, the casting of the impressions, the hardening of the plaster, as well as the preparation of the model by the technician, was 4 hours for conventional impressions.The timing for sending the STL file and modeling the structure was less than 2 hours for the digital scan method. The production time of crowns takes 3 hours for both conventional impressions and digital ones.Of all crowns selected for placement, 46.7% were made from conventional impressions and 53.3% from digital scans. Participants preferred the digital scanning technique (89%) over the traditional impression-taking technique (11%).The data from this study suggest that digital scanning and CAD/CAM technology may be more effective and better accepted by study par-ticipants for a single implant restoration than conventional impressions and plaster casts.