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5、-04 Revised 2013-05 Superseding ARP1923A Qualification and Certification of Etch Inspectors RATIONALE ARP1923B results from a Five Year Review and update of this specification. 1. SCOPE This specification covers the requirements for qualification, requalification, and certification of etch inspector
6、s. 2. REFERENCES There are no referenced publications specified herein. 3. QUALIFICATION REQUIREMENTS Before performing etch inspection on production parts, inspection personnel shall be qualified in accordance with this recommended practice. At qualification and each year thereafter, inspection per
7、sonnel shall pass physical, written, and practical examinations. 3.1 Physical Examination The inspection applicant shall pass a vision test administered by medically qualified personnel with a requirement of reading Ortho-Rater 8, J2 or 20/30 Snellen near vision, at 12 to 16 inches (305 to 406 mm) i
8、n at least one eye, natural or corrected. 3.2 Written Examination At least twenty written questions shall be administered to the inspection applicant. Questions shall include cleaning, operating procedures, and inspection techniques that the applicant would encounter during inspection. A minimum gra
9、de of 80% is required for acceptance. The questions of Appendix A are recommended for this written examination. 3.3 Practical Examination At least three selected specimens representative of actual products shall be tested by the inspection applicant. During these tests, at least ten different check
10、points shall be graded showing an understanding of test variables and an ability to perform etch inspection and correctly interpret its results. During these tests all rejectable parts shall be so rejected and aminimum grade of 80% is required for acceptance. The Appendix B table is a recommended ch
11、ecklist for this practical examination. SAE ARP1923B Page 2 of 15 3.4 Reexamination for Qualification Personnel examined and not meeting qualification standards shall wait 30 days and show evidence of having taken suitable corrective action and additional training or self-study before reexamination.
12、 4. CERTIFICATION REQUIREMENTS Records for all qualified personnel shall be maintained and include date of qualification, results of physical, written, and practical examinations, and experience as a etch inspector. 5. NOTES 5.1 A change bar (l) located in the left margin is for the convenience of t
13、he user in locating areas where technical revisions, not editorial changes, have been made to the previous issue of this document. An (R) symbol to the left of the document title indicates a complete revision of the document, including technical revisions. Change bars and (R) are not used in origina
14、l publications, nor in documents that contain editorial changes only. PREPARED BY AMS COMMITTEE “B“ SAE ARP1923B Page 3 of 15 APPENDIX A - PROPOSED WRITTEN EXAMINATION QUESTIONS AND ANSWERS FOR QUALIFYING ETCH INSPECTORS To examine a prospective inspector, select at least 20 questions as directed be
15、low. Have the selected questions, and only those questions, placed on a separate form. Administer the examination to the prospective inspector without aid of written or printed manner (closed book) with a time limit of 90 minutes. Score the test with partial score for each question permitted. Divide
16、 points scored by the maximum possible to obtain percentage. A percentage of 80 is necessary for acceptance. Personnel examined but not qualifying must wait 30 days and must take suitable corrective action, such as additional training or self-study, before reexamination. Points Topic: Inspector qual
17、ification, select no more than two 2 1. What military standard must be met for near vision requirements to qualify as an etch inspector? Write out answer 2 2. What are the minimum vision requirements for etch inspectors? Write out answer 2 3. At what frequency must etch inspectors be recertified? Wr
18、ite out answer Points Topic: Reason for etch inspection, select not more than one 4 4. What is the etch inspection process attempting to accomplish? Write out answer 3 5. Etch inspection can assist in detecting localized areas of martensitic steel parts that are hardened, softened, or both, due to o
19、verheating during metal removal? Circle correct answer A. True B. False 3 6. Parts can be locally overheated during fabrication. Which of the following fabrication steps can locally overheat martensitic steel parts, the presence of which may be detected by etch inspection? Circle correct answer(s) A
20、. Radiographic inspection B. Drilling C. Grinding D. Magnetic inspection E. Stress relieving SAE ARP1923B Page 4 of 15 Points Topic: Materials, select not more than one 3 7. Which of the following alloys cannot be effectively etch inspected? Circle correct answers A. H-11 B. 440C C. 4340 D. A286 E.
21、PH13-8Mo F. 300M G. D6Ac H. MP35 4 8. Which of the following alloys can be effectively etch inspected? Circle correct answers A. 4340 (200 to 220 ksi) (1379 to 1517 MPa) B. 4330M (220 to 240 ksi) (1517 to 1655 MPa) C. Inconel 718 (220 to 240 ksi) (1520 to 1655 MPa) D. 301 Annealed Points Topic: Solu
22、tion makeup, select not more than two 6 9. The hydrochloric acid solution used during etch inspection is to be made up from technical grade hydrochloric acid (20 Baum). It has been determined that the material on hand meets the specification requirements. If this material is to be used to make up a
23、hydrochloric acid tank of 4 to 6% by volume of technical grade hydrochloric acid and water, how would this be done? Assume a 200 gallon (755 L) tank to be filled about one-half full. Write out answer 6 10. The nitric acid solution used during etch inspection is to be made up from technical grade nit
24、ric acid (40 Baum). It has been determined that the material on hand meets the specification requirements. If this material is to be used to make up a nitric acid tank of 2.5 to 3.5% by volume of technical grade nitric acid and water, how would this be done? Assume a 200 gallon (755 L) tank to be fi
25、lled about one half full. Write out answer 3 11. An ammonium persulfate in water solution may be used as an etching solution. However, this solution will vaporize losing its effectiveness with time. The ammonium persulfate etching solution must be used within how many hours after mixing? Write out a
26、nswer. _ hours SAE ARP1923B Page 5 of 15 3 12. A surfactant is a chemical that is added to a solution to minimize the formation of dark smut on steel when the steel is etched. To what solution must the surfactant be added and in what concentration? Write out answer Points Topic: General process sequ
27、encing of steel parts, select not more than two 4 13. Roll burnishing should be performed before etch inspection? Circle correct answer A. True B. False Why? Write out reason 4 14. Thread rolling should be performed after etch inspection? Circle correct answer A. True B. False Why? Write out reason
28、3 15. Certain steel processing steps can alter the part surface to such an extent as to make etch inspection ineffective. These steps must be performed after etch inspection, some of which are: Circle correct answer(s). A. Chromium plating B. Milling C. Shot peening D. Supplementary phosphate treat
29、2 16. Which are more likely to cause overheating? Circle correct answer A. Machining before heat treatment B. Machining after heat treatment 2 17. When an engineering approved surfactant is used in the etch solution it is not necessary to immerse the parts in a hydrochloric solution. Circle correct
30、answer A. True B. False SAE ARP1923B Page 6 of 15 Points Topic: Tolerances, select not more than one 3 18. Approximately how much material is removed from a surface by etch inspection? Circle correct answer A. 0.00001 to 0.00005 inch (0.0002 to 0.0013 mm) B. 0.0001 to 0.0005 inch (0.002 to 0.013 mm)
31、 C. 0.001 to 0.005 inch (0.02 to 0.13 mm) D. It does not remove metal E. None of the above 3 19. When must very close tolerance parts (less than 0.001 inch (0.02 mm) be dimensionally inspected? Circle single most correct answer A. Before plating B. After final machining C. After etch inspection baki
32、ng prior to plating 3 20. Why must very close tolerance parts (less than 0.001 inch (0.02 mm) be dimensionally inspected after being etch inspected? Write out answer Points Topic: Etch inspection sequencing, select not more than one 8 21. During etch processing, without using a surfactant, the seque
33、ncing of steps must of course be followed. List the following steps in the correct sequence. Step A. Rinse B. Clean C. Hydrochloric Acid (muriatic) Dip D. Nitric Acid (Nital) Dip E. Rinse F. Rinse G. Inspect H. Ink Stamp (acceptable parts) I. Dry J. Rack Parts (not touching) K. Bake L. Oil M. Immers
34、e in Neutralizing Solution N. Rinse SAE ARP1923B Page 7 of 15 10 22. Sixty 4340 steel belleville springs 0.25 inch (6.4 mm) thick with a 4 inch (102 mm) OD and 2 inch (51 mm) ID were ground after heat treatment to 260 to 280 ksi (1793 to 1931 MPa). List in sequence all steps that are required for et
35、ch inspection of these parts; assume no surfactant and that all parts are found acceptable. Points Topic: Etching Process, select not more than two 6 23. Care must be taken during etching to ensure even etching of all surfaces to be inspected. This can be provided by the following: Give at least two
36、 answers A. B. 4 24. Heavy smutting can mask etch indications and requires removal and reprocessing prior to inspecting. Excessive smutting is evident by _. Complete sentence. 4 25. For what reason are parts immersed in hydrochloric acid during acid etch processing? Write out answer 4 26. What cause
37、s heavy smutting during etch inspection? Write out answer Points Topic: Actual visual inspection, select not more than three 6 27. Localized overheating of martensitic steel parts results in these areas being overtempered and softened. This condition, if detected during etch inspection, must be reje
38、cted and is evident as _. Complete the sentence. 6 28. Localized overheating of martensitic steel parts can result in rehardening of these areas without subsequent adequate tempering. This condition, if detected during etch inspection, must be rejected and is evident as _. Complete the above sentenc
39、e. 5 29. To assist in the interpretation of etch results, which of the following may be used? Circle the correct answer(s) A. Comparison with examples B. Visually examine with magnifying glass C. Discuss indication with other certified inspectors or metallurgist. D. Comparison with photographs of re
40、jected parts. E. Have a metallurgical laboratory section a representative part in a questionable area and evaluate or unacceptable condition. F. Perform a superficial hardness test on the area in question. SAE ARP1923B Page 8 of 15 3 30. Acceptable areas during etch inspection appear as uniform _ in
41、 color. What word would correctly complete the above sentence? 3 31. Etch indications tend to run perpendicular (opposite) to the direction of metal removal from the part. Circle the correct answer A. True B. False Points Topic: Baking, select not more than two 3 32. Why is it required to bake parts
42、 that have passed etch inspection without the use of an approved surfactant? Circle correct answer(s) A. Relieve residual surface tensile stresses B. Drive off embrittling hydrogen C. Ensure complete transformation of retained austenite to martensite D. Temper martensite 2 33. It is not necessary to
43、 bake parts that were etch inspected using an engineering approved surfactant in the etch solution and no desmut acid immersion. Circle correct answer A. True B. False 4. 34. What is the correct post etch inspection baking temperature and time? Write out answer _ _ _ _ SAE ARP1923B Page 9 of 15 4 35
44、. After passing etch inspection, parts to be baked at 375 F 25 (191 C 14) for 4 hours would be which of the following: Circle correct answer. A. Placed in a furnace set and recording at 350 to 400 F (175 to 205 C) and held at heat for not less than 4 hours. B. Placed in a furnace with a 25 F (14 C)
45、degrees tolerance that is recording a temperature of 375 F (191 C) and held at that temperature for not less than 4 hours. C. Held in furnace for 4 hours after setting temperature at 375 F (191 C). D. None of the above. 2 36. To ensure adequate process verification records, it is necessary to note o
46、n the bake furnace record chart, the part traveler, or shop order number and the date and time placed in the furnace. A. True B. False Points Topic: Inaccessible areas, select not more than one 2 37. Adequate etch inspection of some areas sometimes cannot be performed due to geometric restrictions i
47、n these areas. Other steps must be taken if assurance is needed that these areas are acceptable. Circle correct answer A. True B. False 2 38. Some areas of parts cannot be adequately etch inspected due to geometric restrictions, such as in small or deep holes machined after heat treatment. For this reason, alternative methods must be used to ensure these areas are acceptable. Which of the following may be used to ensu
