Bridges, buildings, railroads, pipes, vessels, tanks, and other metal or steel welded structures are a vital part of modern infrastructure. These structures are typically fabricated from sets of discrete metal sub-components that are welded together to form a critical component and/or a total system. Welded seams and other weld joining points must be fused into a welded unit having satisfactory strength to ensure building code compliance and to achieve proper structural integrity of the entire system, and/or to ensure meeting the purpose of the design for which it was intended. For example, a pressure vessel or fluid tank must have water tight exterior as well as provide structural support for the entire vessel or tank system. Pipes and vessels similarly must have water or gas sealed, welded seams to ensure the integrity of the pipe/vessel and to properly isolate the fluid or gas held by the pipe from the environment. In addition, these systems deteriorate over time due to operational and environmental factors such as, residual and applied stresses, vibration, rain, snow, strong winds, temperature variance, earthquakes, oxidation, material fatigue, and other changes that occur over the passage of time. Hence, nondestructive testing of welds and metal structures, and their components, are utilized after initial fabrication, installation, and periodically thereafter, to ensure a structure's integrity. Further, both for new construction and routine periodic maintenance, careful analysis of the weld joints in each structure is necessary to ensure satisfaction of various weld specifications, industry codes, and construction regulations. For example, the American Society Mechanical Engineers (“ASME”), the American Welding Society (“AWS”), and the American Petroleum Institute (“API”), among others, each have their own welding codes, procedures, and specifications.
Modern inspectors use non-destructive test (“NDT”) equipment to inspect constructed metal (e.g. steel) structures and their weld joints. These inspection devices use ultrasonic wave generators to take digital “snap-shots” of welds from which an inspector may verify weld integrity and to ensure compliance with welding codes and specifications. Ultrasonic technology is used to detect internal and surface breaking flaws in the weld and the base metal, which are not visible externally, and is based on the principle that a gap or defect in the weld changes the propagation of ultrasonic sound through the metal. One common method of NDT testing uses conventional, single-probe ultrasonic testing requiring an operator's interpretation of a screen similar to an oscilloscope screen that presents time and amplitude information. Another method uses an array of ultrasonic phased array sensors to test a structure. Such methods can be combined into a single digital piece of inspection equipment that uses phased array (“PA”) and time-of-flight (“TOFD”) diffraction methodologies to provide a three dimensional image of a weld displayed on a color screen. An inspector then evaluates the potential for a flaw or defect in the weld by reviewing the screen. Such ultrasonic testing (“UT”) equipment is typically highly mobile, and allows for the recordation of ultrasonic data for the analysis of welded areas in joined metal pieces. For example, Olympus NDT, Inc. markets and sells ultrasonic units through its OmniScan™ and Epoch™ lines of weld flaw detectors. The Olympus ultrasonic inspection systems include conventional ultrasonic flaw detectors, which use ultrasonic waveforms to detect flaws, and advanced ultrasonic phased array flaw detectors, which create internal cross-section images of the areas being inspected. These ultrasonic flaw detectors may also be configured to do a phased array ultrasonic testing (“PAUT”) inspection that produces encoded digital data points on welds which may be further processed at a later time. The data may also be reviewed later at a time convenient for an inspector and in an environment away from the component or structure's location, which is typically more suitable for detailed analysis work. Such ultrasonic data is recorded and saved in large data files which may be retrieved for evaluation by an inspector using specialized software applications. While these data files are readable by the ultrasonic testing device, software applications also exist that assist in the evaluation and visual display of such inspection data on common computing devices, such as a PC. An example of such applications is the OmniPC™ analysis software also available from Olympus NDT, Inc., along with an additional analysis tool set called TomoView™. Both of these tools allow for a more precise and reliable review of the three dimensional PA data by an inspector.
A phased array data file consists of captured data representative of continuous A-scans along a weld which may be processed to create a three dimensional data set representative of the top, side, and end views of a weld joint. Within each A-scan, a series of recorded data points record an intensity or amplitude value from 0% to 100% of ultrasonic signal reflections. These data points are then saved as OPD, RTD or TV file formats for subsequent analysis. Since the recordation of ultrasonic data is correlated to the exact PA probe position on the structure being tested, the inspector may use the analysis software including various sets of sophisticated analysis tools to review the recorded data in a number of geometric views and orientations (e.g. top view, side view, end view) to improve inspection review accuracy.
Further information regarding the use of phased array UT equipment, configuring such UT equipment, establishing a test scan plan applicable to a particular inspection or weld joint design situation, the recording of that data in various file formats, the physics and geometries of the ultrasonic sound beams and resulting scanning views in UT, the use and applicability of “data” libraries, the storing of testing data files, the usage of different types of scan views, the visual analysis of weld flaw indications, and the generation of inspection reports based upon UT shall not be discussed herein as such information is well known known in the NDT industry and not necessary for a complete understanding of the disclosed invention. However, Applicant references and hereby incorporates by reference the treatise UT Classroom Training Book, Paul T. Marks, ISDN No. 978-1-57117-345-4 (e-book), published by The American Society for Nondestructive Testing, and two treatises published by Olympus NTD, Inc: (1) Introduction to Phased Array Ultrasonic Technology Applications, third printing 2007, ISBN No. 0-9735933-4-2; and (2) Advances in Phased Array Ultrasonic Technology Applications, 2007, ISBN No. 0-9735933-4-2. The books may be obtained at the ASNT website www.asnt.org or the Olympus NDT resources website www.olympus-ims.com. These treatises explain the above subjects in detail and the general theory of UT using modern equipment. Further, Applicant references and hereby incorporates by reference U.S. Pat. Nos. 8,156,813B2, 8,577,629B2, 9,032,802B2, 9,081,490B2. These patents discuss and disclose background information regarding the electronics and theory behind PA ultrasonic testing.
Nevertheless, even with modern PA and time-of-flight UT devices, and even when inspection analysis is conducted in an environment conducive for careful study, the data analysis and reporting process can be a tedious and fatiguing task for inspectors. For example, metal pipe and plate structures typically have girth welds and long seams that must be inspected. PA ultrasonic and time-of-flight, diffraction inspection for those welds seams can produce extremely large data files requiring many hours of data review and analysis of all data points along the weld seams by an inspector. Usually most of the data points are nominal, satisfactory welds, creating a monotonous review period and potentially reducing weld flaw recognition by an inspector due to fatigue. Hence, what would enhance the inspection process would be a system for focusing an inspector's attention on actual weld defect indications, by excluding data points that present satisfactory and acceptable weld characteristics. Such a system would improve an inspector's efficiency and accuracy in conducting new or reviewing prior weld inspections, thereby saving time and money.