T9074-AS-GIB-010/271 Rev 1
whether the contrast is sufficient. Since the pipe edge image contrast will also be degraded with fluid in the pipe and when corrosion product exists on the pipe surface, the procedure shall also address these conditions. The procedure shall define the sequence of image processing and enhancement (window and leveling, edge enhancement filters, etc.) to be applied to generate the wall thickness measurement. This same sequence shall be applied to obtain the known reference standard measurement exposed in the same image. A.5.6 Exposure/Pixel Value. The unprocessed image pixel values must be mapped so that smaller pixel values correspond to lower X-ray dose and larger pixel values correspond to higher X-ray dose. Imaging plate exposure shall be sufficient to expose an area in the inside diameter pipe region to a pixel value of at least 10 percent of the maximum pixel value or 1024 pixel counts, whichever is less. The maximum pixel value will depend on the bit depth of the CR system. The maximum pixel value in the measurement region adjacent to both the inside and outside diameter of the pipe wall shall not exceed 95 percent of the system maximum pixel value (saturation). A.6 INADVERTENT RADIOGRAPHY. For the purposes of CR inspection of piping systems for corrosion/erosion, inadvertent radiography is defined as the presentation of welds captured incidental to pipe and fitting CR imaging. All welds that are inadvertently imaged during corrosion/erosion inspections using CR shall be evaluated by the Level II Inspector to the maximum extent practicable from the given image. Discontinuities shall be evaluated as follows: a. Cracks and crack-like indications shall be rejected. b. Discontinuities in S9074-AR-GIB-010/278 Class P1 pipe welds shall be evaluated in accordance with MIL-STD-2035 Class 1 weld inspection requirements. c. S9074-AR-GIB-010/278 Class P2 pipe welds shall be evaluated for incomplete penetration (IP) and incomplete fusion (IF). The Level II Inspector shall notify the NDT Examiner when IP or IF appears to extend into the weld or when associated with corrosion or erosion. An Engineering Evaluation, as defined in MIL-STD-2035, is required when the Level III Examiner determines that corrosion or erosion is associated with IP/IF or when the thickness of the weld metal is reduced by 25 percent or more as a result of the IP/IF.
A.7 RECORDS. CR radiographic records shall contain the following as a minimum: a. The radiographic records required by Chapter 3 apply to CR.
b. Each inspection image file shall be traceable to the identification of the original software manufacturer and version used to perform the original production inspections. Each CR storage media (optical, magnetic drive, flash, etc.) shall be permanently marked with the manufacturer and version of the review and archiving software platforms used to perform the original production inspection. c. The inspection records and image files shall be provided to the customer. The format of the image files shall be such that they can be viewed and manipulated with a minimum capability of zoom, brightness, contrast and ability to measure pipe wall thickness using an embedded limited version of the CR system vendor’s software and a generic Microsoft Windows compatible computer. d. The inspection activity shall maintain copies of all inspection records (hard copy or electronic) for the time period specified in the fabrication document requirements. In addition, all original electronic data files, including a backup data file, shall be maintained. The electronic data shall be such that the data can be re-evaluated with the original or updated compatible software for a period of at least 5 years.
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