T9074-AS-GIB-010/271 Rev 1
5.6 TEST PROCEDURES.
5.6.1 Order of Testing. All liquid penetrant tests shall be performed prior to ultrasonic inspections on the same surfaces to avoid interference between the penetrant dye and any residual couplant. If liquid penetrant tests must be performed after ultrasonic inspection, and a couplant other than water without an additive is used, a special cleaning operation shall be used. This special cleaning operation shall be defined in a local procedure, qualified in a manner similar to the procedure of 5.6.2.1, and approved by the activity's NDT Examiner. 5.6.2 Pre-Test Cleanliness. Prior to liquid penetrant inspection, the surface to be tested shall be dry and free of dirt, grease, lint, scale and salts, coatings, or other extraneous matter that would obscure surface openings or otherwise interfere with the test. Any adjacent area within one inch of the surface to be tested (for welds, any area within one inch from the toe of the weld) shall be dry and free of any foreign material that might contaminate the dye or otherwise interfere with the inspection. If a nonvolatile liquid is used for cleaning, the surface shall be heated or dried with hot air to assure complete removal of the cleaner. As a final cleaning operation each surface shall be dipped, sprayed, wiped, or brushed with, acetone, denatured ethanol (ethyl alcohol), isopropanol (isopropyl alcohol), or alternate cleaner/removers supplied by penetrant manufacturers which meet the requirements of SAE AMS 2644 and have been qualified in accordance with 5.6.2.1. Surfaces shall then be thoroughly dried by removing the excess with a clean dry cloth or absorbent paper, and allowing the remainder to evaporate for an appropriate drying time as follows: Solution Method of Application Evaporation Time Acetone Any 5 minutes Alcohol Wiping with dampened cloth or absorbent paper 5 minutes Alcohol Other than wiping 20 minutes Other As established (See 5.6.2.1) As established (See 5.6.2.1) 5.6.2.1 Qualification of Alternate Precleaners. Other precleaners may be used for the final cleaning operation provided they meet the halogen and sulfur requirements of 5.3.1 and are qualified as follows: (Note that any precleaners qualified according to the following paragraphs shall only be used with the same air circulation (forced vs. natural) and temperature conditions used in the qualifying process.) a. The performance of the proposed cleaner, method of application, and associated drying time/temperature combination shall be compared to the performance of acetone through the use of three SAE AMS 2644 Type 2 penetrant system test panels (aluminum quench crack panels). The panels shall be soaked in an oil-based cutting fluid for 24 hours prior to the evaluation. b. The acceptability of the proposed precleaner, method of application, and drying time/temperature combination shall be based on a comparison of the results obtained with the candidate procedure (using the minimum drying time/temperature combination (within 20 °F), and circulating air, if specified) versus acetone using a five minute drying time. All of the other procedure parameters shall be the same for the two trials. The minimum penetrant dwell time and the minimum development time allowed by the procedure shall be used. If, in the opinion of the Examiner, the indications obtained with the proposed precleaner and associated drying time/temperature combination are essentially the same as those obtained with the acetone, the precleaner and associated drying time/temperature is qualified for use. c. Documentation of the qualification shall include the signature of the Examiner and shall be provided to the Government inspector upon request. 5.6.3 Temperature. Maximum penetration into extremely small openings requires that the penetrant and the test surface be maintained at the temperature recommended by the penetrant manufacturer but shall not be less than 50 °F. The temperature of the penetrant and the test surface shall not be greater than 100 °F, except that for Type 2 Method C materials the temperature of the test surface may be a maximum of 150 °F or the maximum temperature recommended by the manufacturer, whichever is less. Due to the flammable nature of liquid penetrant inspection materials, the use of an open flame for heating
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