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Appendix D Ultrasonic Anchor Inspection Procedure
Fish Inspection and Testing LLC Ultrasonic Anchor Bolt Inspection Procedure
This procedure when specified shall be the method used to ultrasonically examine bolts to locate fatigue cracks perpendicular to bolt length.
ASME Section V
American Welding Society D1.1
Qualification and Certification of NDT Personnel
Control of Measuring and Test Equipment
The personnel implementing this procedure shall be certified in accordance with Fish Inspection and Testing LLC NDE Quality Assurance Manual "Qualification and Certification of NDT Personnel," as either Level II or III to evaluate results, or Level I to perform the operational portion of the examination and record data while under the direct supervision of a Level II or III.
Equipment and Material
Equipment and materials used to implement this procedure will be calibrated and certified in accordance with Fish Inspection and Testing LLC NDE Quality Assurance Manual "Control of Measuring and Testing Equipment." A copy of the equipment and material certifications wilt be available at the request of the client.
The ultrasonic instrument shall be a Pulse-Echo type unit equipped with an A scan presentation and capable of generating frequencies over the range of 1 MHz to 5 MHz. The instrument will also be equipped with a calibrated attenuator in one (1) or two (2) db steps with an accuracy over its range of ± 2db.
Calibration blocks shall be either International Institute of Welding (11W) Type I of Type II or Distance and Sensitivity Calibration Block (DSC) used in conjunction with calibration standards of Paragraph D. At the option of the client, specific calibration standards can be prepared at their discretion to verify adequacy of this procedure.
Calibration standards shall be made out of the same or similar material as the bolts being examined. The standard shall be made of material free of indications that may affect calibration. The optional standards should be of the same diameter and length and material type as the bolts being examined. The standards shall be machined with a 1/8 inch deep saw cut below the root of the threads. The saw cut shall be located at 2 inches, 4 inches, 6 inches, and 8 inches from the threaded end of the bolt. The saw cut shall be located perpendicular to the end of the bolt. The end of the bolt shall be flat and smooth as to not interfere with free movement of the search unit. The saw cuts shall be located in different quadrants so they do not mask the notch below.
Prerequisites, Precautions and Limitations
The surface of the test material shall be flat, smooth and in its final condition prior to the examination. This may require the use of hand grinders to facilitate search unit movement.
The same equipment used for calibration shall be the same as used for examination purposes. This includes the ultrasonic instrument, cables, search unit and couplant. Any change in this equipment requires recalibration.
This procedure may be used for 1/2 inch to 3-inch diameter bolts. The area of interest shall be the first ten inches. If the area past the first ten inches is to be examined, further evaluation should be performed before using this procedure with special attention to beam spread and mode conversion. This evaluation will be performed by Fish Inspection and Testing LLC level ultrasonic examiner and results approved by the client prior to any examinations.
The surface to be examined shall be smooth and tee of roughness or other conditions that would interfere with free movement of the search unit or impair the transmission of ultrasonic waves. The nut should be fully threaded past the end of the bolt so as not to interfere with search unit scanning area.
Straight Beam Examination of Bolts
System Calibration Check
Evaluation and Recording of Results
All defects or discontinuities revealed by the examination will be evaluated in accordance with Paragraph C2 and reported to the client.