Detect Tank Services, LLC Magnetic Particle Examination Procedure PDF

Technical Procedure: DTS-014-MP MAGNETIC PARTICLE EXAMINATION DATE December 10, 2019 REVISION 2 PAGES 21 PREPARED BY LL REVISION BY DRW APPROVED BY JE  MTI-014-MP DETECT TANK SERVICES, LLC...

Technical Procedure: DTS-014-MP MAGNETIC PARTICLE EXAMINATION DATE December 10, 2019 REVISION 2 PAGES 21 PREPARED BY LL REVISION BY DRW APPROVED BY JE  MTI-014-MP DETECT TANK SERVICES, LLC Rev. 2 Revised By: DW MAGNETIC PARTICLE EXAMINATION January 31, 2015 Approved by: AA Minimum Inspection Requirements Page 2 of 21 1.0 Purpose The purpose of this procedure is to establish the minimum requirements for magnetic particle inspection to detect surface or subsurface discontinuities in carbon steel aboveground storage tank components. 2.0 Scope 2.1 The requirements of this procedure apply to Detect Tank Services, LLC. personnel performing magnetic particle. 2.2 Code-specific Procedures, Interpretation and Acceptance Standards are covered in the relative code below. If there is a conflict between this procedure and a specific code, the requirements of the updated Code shall govern. 3.0 References 3.1 ASME Boiler and Pressure Vessel Code Section I, V, VIII, IX and SE- 1316; 2004 Edition. 3.2 ASME B31.1 - 2004 Edition, B31.3 - 2004 Edition, B31.4 - 2004 Edition, B31.8 2004 Edition 3.3 AWWAD100-96 3.4 AWS D1.1-2006 3.5 MIL-STD271F 3.6 MIL-STD 1949A 4.0 Definitions Definitions shall be as defined in ASME SE-1316, Standard Terminology for Nondestructive Examinations. 5.0 Personnel Requirements Personnel performing and/or evaluating magnetic particle examinations under this procedure shall be qualified and certified to at least Level II in MT per SNT-TC-1A. 6.0 Equipment 6.1 Parker DA 400 articulating yoke or equivalent 6.2 Spectroline black light or equivalent 6.3 Detek D-250 pie gauge or equivalent  MTI-014-MP DETECT TANK SERVICES, LLC Rev. 2 Revised By: DW MAGNETIC PARTICLE EXAMINATION January 31, 2015 Approved by: AA Minimum Inspection Requirements Page 3 of 21 7.0 Procedure 7.1 The sensitivity of the magnetic particle examination method is greatest for surface discontinuities and diminishes rapidly with increasing depth of subsurface discontinuities below the surface. Satisfactory results are usually obtained when the surfaces are in the as-welded, as-rolled, as-cast or as-forged conditions. However, surface preparation by grinding or machining may be necessary where surface irregularities could mask indications due to discontinuities. 7.2 For optimum effectiveness in detecting all types of discontinuities, each area shall be examined at least twice, with the lines of flux during one examination approximately perpendicular to the lines of flux during the other with sufficient overlap to assure 100% coverage at the required sensitivity. A different technique for magnetization may be used for the second examination. 7.2.1 Weld testing shall start at a specific reference point and proceed in a direction until full coverage (100%) has been achieved, including at least one inch of parent material on each side of the weld. 7.2.2 On large surfaces, it is a good practice to layout a grid for the prod or yoke placement. 7.2.3 All testing shall be done using the continuous method (i.e. the magnetizing current shall be on continuously while the wet or dry particles are being applied and while the excess dry particles are removed.) 7.2.4 Prior to magnetic particle examination, the surface to be examined and all adjacent areas within at least one inch shall be dry and free of all dirt, grease, lint, scale, welding flux and spatter, oil or other extraneous matter that could interfere with the examination. 7.2.5 Magnetizing units equipped with meters shall have affixed to it a sticker showing the last date of performance and accuracy tests. Performance and accuracy tests shall be done in accordance with the manufacturer’s recommendations and referencing code, standard or specification, and the results of such action recorded and maintained on file. 7.2.6 Prod tips may be of copper, and be of the solid or the copper- electrode type. Lead, steel or aluminum prods may be used where copper penetration into the test item must be avoided. MTI-014-MP DETECT TANK SERVICES, LLC Rev. 2 Revised By: DW MAGNETIC PARTICLE EXAMINATION January 31, 2015 Approved by: AA Minimum Inspection Requirements Page 4 of 21 7.3 Light intensity for examination of white light: 7.3.1 The intensity of the visible light at the surface of the part undergoing examination shall be a minimum of 100 foot-candles. The intensity of ambient visible light in the darkened area where fluorescent magnetic particle examination is performed should not exceed two foot-candles. 7.3.2 For field inspections using non-fluorescent particles, visible light intensities as low as 50 foot-candles may be used when agreed to by the customer. 7.4 Black light 7.4.1 The black light shall be allowed to warm up for a minimum of five minutes prior to use or measurement of the intensity of the ultraviolet light emitted. 7.4.2 The black-light intensity shall be measured with a black-light meter and shall provide a minimum of 1000 uW/cm2 on the surface of the part being examined. The black light intensity shall be measured at least once every eight hours. 7.5 Dark area eye adaptation 7.5.1 The examiner shall be in the darkened area for at least five minutes prior to performing the examination to enable his eyes to adapt to dark viewing. 7.6 Magnetic Particle Materials 7.6.1 Whether using a wet or dry method, the color of the particles shall provide adequate contrast with the surface being examined. 7.7 Dry Particles 7.7.1 Dry particles shall meet the requirements of AMS 3040. 7.7.2 Magnetic particle examination shall not be performed if the surface temperature of the part exceeds 600°F. 7.7.3 Additional requirements specific to the use of dry particles are given in E 709-01, Standard Guide for Magnetic Particle Examination. 7.8 Wet Particles 7.8.1 The temperature of the wet particle suspension and the surface of the part shall not exceed 135°F. MTI-014-MP DETECT TANK SERVICES, LLC Rev. 2 Revised By: DW MAGNETIC PARTICLE EXAMINATION January 31, 2015 Approved by: AA Minimum Inspection Requirements Page 5 of 21 7.8.2 The concentration of non-fluorescent material shall be 1.2 to 2.4 mL from a 100 mL sample. 7.8.3 For MIL-STD-271, the concentration is the same as 7.8.2 above. 7.8.4 For MIL-STD-1949: 7.8.4.1 Wet particles shall meet the requirements of AMS 3041, 3042, 3043, 3044, 3045 or 3046 as applicable. 7.8.4.2 The suspension vehicle shall be a light petroleum distillate conforming to AMS 2641 (Type I) or to DOD-F-87935 or a suitably conditioned water. When approved by the contracting agency, AMS 2641 (Type II) may be used. 7.8.4.3 The concentration is the same as 7.8.2 above. 7.9 Conditioned Water — to achieve the above concentrations, mix the following quantities of Dubi-Chek material: 7.9.1 Mix 3 tsp & 1/8 tsp of W5C Conditioner per gallon of water and; 7.9.2 Mix 3/8 tsp of GW1 Glo-Netic per gallon of water. 7.10 Fluorescent Particles 7.10.1 The concentration of fluorescent material shall be 0.1 to 0.4 mL from a 100 mL sample. 7.10.2 For MIL-STD-271, the concentration of fluorescent material shall be from 0.1 to 0.70 mL for a 100 mL sample. 7.10.3 For MIL-STD-1949A, the concentration of fluorescent material is the same as 7.9.1 above. 8.0 Magnetizing Field Adequacy and Direction 8.1 When it is necessary to verify the adequacy or direction of the magnetizing field, the magnetic particle field indicator shall be used by positioning the indicator on the surface to be examined. A clearly defined line of magnetic particles formed across the copper face indicates a suitable flux or field strength when the magnetic particles are applied simultaneously with the magnetizing force. When a clearly defined line of particles is not formed, or is not formed in the desired direction, the magnetizing technique shall be changed or adjusted. 8.2 The magnetic particle field indicator is only permitted for determining field adequacy when specifically referenced by the magnetizing technique. MTI-014-MP DETECT TANK SERVICES, LLC Rev. 2 Revised By: DW MAGNETIC PARTICLE EXAMINATION January 31, 2015 Approved by: AA Minimum Inspection Requirements Page 6 of 21 9.0 Calibration of Equipment 9.1 Equipment equipped with an ammeter 9.1.1 Frequency: Each piece of magnetizing equipment with an ammeter shall be calibrated at least once a year, or whenever the equipment has been subjected to major electrical repair, periodic overhaul or possible damage. If equipment has not been in use for a year or more, calibration shall be done prior to the first use. 9.1.2 Procedure: The accuracy of the ammeter shall be verified annually by equipment traceable to a national standard. Comparative readings shall be taken for at least three different current output levels encompassing the useable range. 9.1.3 Tolerance: The ammeter reading shall not deviate by more than ±10% of full scale, relative to the actual current value as shown by the test meter. 9.2 Lifting Power of Yokes 9.2.1 The magnetizing force of yokes shall be checked at least every six months, or whenever a yoke may have been damaged. 9.2.2 Each alternating electromagnetic yoke shall have a lifting power of at least ten pounds at the maximum pole spacing used. 9.2.2.1 MIL-STD-1949A; Alternating current yokes shall use a pole spacing of two inches to four inches for this test. 9.2.3 Each direct current or permanent magnetic yoke shall have a lifting power of at least 40 lb at the maximum pole spacing used. 9.2.3.1 MIL-STD-1949A; Direct current yokes shall have a lifting force of at least 30 lb with a two to four inches pole spacing or 50 pounds with four to six inches pole spacing. 9.2.4 Each weight shall be weighed with a scale from a reputable manufacturer and stenciled with the applicable nominal weight prior to the first use.  MTI-014-MP DETECT TANK SERVICES, LLC Rev. 2 Revised By: DW MAGNETIC PARTICLE EXAMINATION January 31, 2015 Approved by: AA Minimum Inspection Requirements Page 7 of 21 10.0 Pre-Inspection 10.1 Pre-inspection shall be made of the test item to determine that surface conditions including plating, equipment requirements, accessibility, masking, plugging and all other test parameters can be met. Weather conditions of temperature, humidity, wind, etc., should be considered as a test parameter, particularly if the test item is exposed to the elements. 10.2 If all test parameters cannot be met, the technician shall inform the system owner or his designate. Testing shall not continue until all test parameters have been met or otherwise accepted. 11.0 Surface Preparation 11.1 The component shall be checked for residual magnetism with a suitable field indicator or Gauss meter prior to examination. The component may require demagnetizing if a residual field is present. 11.2 The surface to be examined and all adjacent areas within at least one inch shall be dry and free of all dirt, grease, oil, paint, loose scale or other conditions, such as coatings, that might interfere with accurate interpretations of indications. If coatings are left on the part in the area being examined, it must be demonstrated that indications can be detected through the existing maximum coating thickness applied. 11.3 Cleaning may be accomplished using detergents, organic solvents, descaling solutions, paint removers, vapor degreasing, sand or grit blasting or ultrasonic cleaning methods. Materials and methods used for cleaning the test surface shall meet the requirements of the system owner. 11.4 Any surface finishing done after Magnetic Particle examination shall be re-tested and the results recorded as the final test. 12.0 Prod Technique 12.1 Testing of welds shall be done using the prod or yoke and dry powder method. Prod spacing shall not exceed eight inches. Shorter prod spacing, to a minimum of three inches, may be used to increase sensitivity or accommodate the geometry of the test part.  MTI-014-MP DETECT TANK SERVICES, LLC Rev. 2 Revised By: DW MAGNETIC PARTICLE EXAMINATION January 31, 2015 Approved by: AA Minimum Inspection Requirements Page 8 of 21 12.2 Magnetizing Current 12.2.1 ASME 12.2.1.1 For sections less than 3/4 inch in thickness - from 90 to 100 amp/inch of prod spacing. 12.2.1.2 For sections 3/4 inch thick or greater - 100 to 125 amp/inch of prod spacing. 12.2.1.3 If the open circuit voltage of the magnetizing current source is greater than 25V, lead, steel or aluminum (rather than copper) tipped prods should be used to avoid copper deposits on the part being examined. 12.3 MIL-STD-271 12.3.1 100 to 125 amp/inch of prod spacing. 12.4 MIL-STD-1949 12.4.1 For sections 3/4 inch and under in thickness use from 90 to 115 amp/inch, of prod spacing. 12.4.2 For material over 3/4 inch thick use from 100 to 125 amp/inch, of prod spacing. 13.0 Longitudinal Magnetization 13.1 If a fixed, pre-wound coil is used, the part shall be placed near the side of the coil during inspection. This is of special importance when the coil opening is more than ten times the cross-sectional area of the test part. 13.2 Magnetic Field Strength Guidelines: Direct or rectified current shall be used to magnetize parts examined by this technique. The required field strength shall be calculated based on the length L and the diameter D of the part in accordance with 12.4.1, 12.4.2, or as established in 13.2.1 below. Long part shall be examined in sections not to exceed 18 inch and 18 inch shall be used for the part L in calculating the required field strength. For non-cylindrical parts, D shall be the maximum cross-section diagonal. 13.2.1 Parts with L/D Ratios Equal to or Greater Than 4. The magnetizing current shall be within ±10% of the ampere-turns’ value determined as follows: NI=35,000/(LD)+2 MTI-014-MP DETECT TANK SERVICES, LLC Rev. 2 Revised By: DW MAGNETIC PARTICLE EXAMINATION January 31, 2015 Approved by: AA Minimum Inspection Requirements Page 9 of 21 Where: N = Number of turns in the coil I = Amperage L = Part length, inch (to a maximum of 18 inch) D = Part Diameter, inch 13.2.2 Parts With L/D Ratios Less than 4 but Not Less Than 2 Positioned Close to the Inside Wall of the Coil. The magnetizing ampere-turns shall be within ±10% of the ampere-turns’ value determined as follows: NI = 45,000/L / D Where: N = Number of turns in the coil I = Amperage L = Part length, inch (to a maximum of 18 inch) D = Part Diameter, inch 13.2.3 Parts With L/D Ratios Less than 4 but Not Less Than 2 Positioned in the Center of the Coil. The magnetizing ampere-turns shall be within ±10% of the ampere-turns’ value determined as follows: 43,000R/6L / D—5 Where: N = number of turns in the coil, I = coil current to be used, 12.4.1, R = Coil Radius, inch, L = Part length, inch (to a maximum of 18 inch) D = part diameter, inch NI = ampere turns 13.2.4 If the area to be magnetized extends beyond 6 inch on either side of the coils, field adequacy shall be demonstrated using the magnetic field indicator. 13.2.5 For large parts, due to size and shape, the magnetizing current shall be 1,200 ampere-turns to 4,500 ampere-turns. The field adequacy shall be demonstrated using the magnetic field indicator.  MTI-014-MP DETECT TANK SERVICES, LLC Rev. 2 Revised By: DW MAGNETIC PARTICLE EXAMINATION January 31, 2015 Approved by: AA Minimum Inspection Requirements Page 10 of 21 13.3 Magnetizing Current: The current required to obtain the necessary magnetizing field strength shall be determined by dividing the ampere- turns obtained in step 12.4.1 or 12.4.2 by the number of turns in the coil as follows: I=NI/N 14.0 Circular Magnetization - Magnetic field strength guidelines. 14.1 Direct Contact Technique 14.1.1 Magnetizing Procedure. Magnetization is accomplished by passing current through the part to be examined producing a circular magnetic field approximately perpendicular to the direction of current flow within the part. 14.1.2 Magnetizing Current. Direct or rectified (half-wave rectified or full-wave rectified) magnetizing current shall be used. 14.2 The current shall be 300 amp/inch, to 800 amp/inch, of outside diameter. 14.3 Parts with geometric shapes other than round, with the greatest cross- sectional diagonal in a plane at right angles to the current flow, shall be used to determine the inches to be used in 14.1 above. 14.4 If the current levels required for 12.4.2 cannot be obtained, the maximum current obtainable shall be used and the field adequacy shall be demonstrated by using the magnetic particle field indicator. For non- cylindrical parts and when examining large parts by clamping the contacts to the wall thickness, field adequacy shall be demonstrated by using the magnetic field indicator. 14.5 MIL-STD-1949A 14.5.1 The magnetizing current shall be the same as 14.2. The diameter of the part shall be taken as the largest distance between two points on the outside circumference of the part. Normally, currents will be 500 A/inch or lower with the higher currents (up to 800 A/inch) being used to inspect for inclusions or to inspect low permeability alloys such as precipitation hardening steels. For tests used to locate inclusions in precipitation hardened steels, even higher currents up to 1000 A/inch may be used. 14.6 Central Conductor Technique 14.6.1 Magnetizing Procedure. For this technique, a central conductor is used to examine the internal or external surfaces of ring or  MTI-014-MP DETECT TANK SERVICES, LLC Rev. 2 Revised By: DW MAGNETIC PARTICLE EXAMINATION January 31, 2015 Approved by: AA Minimum Inspection Requirements Page 11 of 21 cylindrically shaped parts. Where large diameter cylinders are to be examined, the conductor shall be positioned close to the internal surface of the cylinder. When the conductor is not centered, the circumference of the cylinder shall be examined in increments, and a magnetic particle field indicator shall be used to determine the extent of the arc that may be examined for each conductor position. 14.6.2 Magnetizing Current. The field strength required shall be equal to that determined in 14.5.1 for a single turn central conductor. The magnetic field will increase in proportion to the number of times the central conductor cable passes through a hollow part. When the central conductor technique is used, magnetic field adequacy shall be verified using a magnetic particle field indicator. 14.6.3 MIL-STD-l949A 14.6.3.1 Centrally Located Conductor: When the axis of the central conductor is located near the central axis of the part the same current levels as given in paragraph 7.1.3 shall apply. 14.6.3.2 Offset Central Conductor: When the conductor passing through the inside of a part is placed against an inside wall of the part, the current levels as given in paragraph 7.2.1 shall apply, except that the diameter shall be considered the sum of the diameter of the central conductor and twice the wall thickness. The distance along the part circumference (interior or exterior) which is effectively magnetized shall be taken as four times the diameter of the central conductor. The entire circumference shall be inspected by rotating the part on the conductor, allowing for approximately a 10 percent magnetic field overlap. 15.0 Yoke Technique 15.1 This technique shall only be applied to detect discontinuities that are open to the surface of the part. 15.2 For this technique, alternating or direct current electromagnetic yokes, or permanent magnet yokes may be used. 15.3 Except for materials 1/4 inch or less in thickness, alternating current yokes are superior to direct or permanent magnet yokes of equal lifting power for the detection of surface discontinuities.  MTI-014-MP DETECT TANK SERVICES, LLC Rev. 2 Revised By: DW MAGNETIC PARTICLE EXAMINATION January 31, 2015 Approved by: AA Minimum Inspection Requirements Page 12 of 21 16.0 Multi-Directional Technique 16.1 Magnetizing Procedure: For this technique, magnetization is accomplished by high amperage power packs operating as many as three circuits that are energized one at a time in rapid succession. The effect of these rapidly alternating magnetizing circuits is to produce an overall magnetization of the part in multiple directions. Circular or longitudinal magnetic fields may be generated in any combination using the various techniques described in 12.0. 16.2 Magnetic Field Strength: Only three phase, full-wave rectified current shall be used to magnetize the part. The initial magnetizing current requirements for each circuit shall be established using the previously described guidelines. The adequacy of the magnetic field shall be demonstrated in accordance with VII, and a magnetic particle field indicator shall be used to verify that an adequate field is obtained in at least two nearly perpendicular directions. For areas where adequate field strengths cannot be demonstrated, additional magnetic particle techniques shall be used to obtain the required directional coverage. 17.0 Evaluation 17.1 Acceptance Criteria 17.1.1. Examination shall be done immediately after the excess powder has been removed and before changing the position of the prods. 17.1.2 All indications shall be evaluated to the applicable Code or Specification designated by the customer in terms of the acceptance standards for these Code Sections listed in the attached appendices. 17.1.3 In the absence of a criteria specified by the customer, evaluation criteria will be selected in the following order: 17.1.3.1 The particular code that would normally apply to the specific job. 17.1.3.2 ASMEB31.l 17.1.3.3 MIL-STD-271 inspections shall be evaluated in accordance with MIL-STD 278 or NAVSHIPS 0900-003- 8000 unless otherwise specified by the contract or the customer.  MTI-014-MP DETECT TANK SERVICES, LLC Rev. 2 Revised By: DW MAGNETIC PARTICLE EXAMINATION January 31, 2015 Approved by: AA Minimum Inspection Requirements Page 13 of 21 18.0 Relevant/Non-Relevant Indications 18.1 Discontinuities on or near the surface are indicated by retention of the examining medium. However, localized surface irregularities due to machining marks or other surface conditions may produce false indications. 18.2 Broad areas of particle accumulation which might mask indications from discontinuities are prohibited, and such areas shall be cleaned and reexamined. 18.3 Relevant indications are those which result from mechanical discontinuities. 18.4 Non-relevant indications are those which result from certain metallurgical and magnetic permeability variations, which may produce indications similar to those of relevant indications; but shall not be ruled unacceptable. Non-relevant indications which might possibly conceal unacceptable discontinuities shall be treated as unacceptable unless removed or examined by another method. 18.5 All unacceptable indications will be marked on the test piece and documented. 18.6 Arc strikes in accordance with MIL-STD-271 or E709 shall be ground out and re-inspected, using the prod or yoke method or visually inspected at 5X magnification. 19.0 Demagnetization and Post Cleaning 19.1 Demagnetization 19.1.1 A field indicator shall be used to determine the residual field left in the test part (should not exceed 2 gauss). Whenever possible, parts which have been circularly magnetized shall be magnetized in the longitudinal direction before being demagnetized. 19.1.2 For the maximum effectiveness, if possible, parts should be oriented with their major axis in the east-west direction during demagnetization to eliminate the effects of the earth’s magnetic field. 19.1.3 Alternating Current Demagnetization 19.1.3.1 The part shall be subjected to a field with a peak value greater than, and in nearly the same direction as, the field  MTI-014-MP DETECT TANK SERVICES, LLC Rev. 2 Revised By: DW MAGNETIC PARTICLE EXAMINATION January 31, 2015 Approved by: AA Minimum Inspection Requirements Page 14 of 21 used during inspection. This alternating current field is then gradually decreased to zero. 19.1.3.2 When using a coil, hold the part approximately 1 ft. in front of the coil and then move it slowly and steadily through the coil and approximately 3 ft. beyond the end of the coil. Repeat this process as necessary. Rotate and tumble parts of complex configuration while passing through the field of the coil. 19.2 Direct Current Demagnetization 19.2.1 The initial field shall be higher than and in nearly the same direction as the field reached during magnetization. The field shall then be reversed, decreased in magnitude, and the process repeated (cycled) until an acceptably low value of residual field is reached. 19.2.1.1 Post Cleaning 19.2.1.1.1 Post cleaning of a test item to be inspected with the dry powder method may be done by brushing or by using air. 19.2.1.1.2 Post cleaning of a test item to be inspected with the wet fluorescent method may be done by wiping with a cloth and a cleaner approved by the system owner. 20.0 Test Reports 20.1 Report of Nondestructive Testing 20.1.1 The results of the Magnetic Particle examinations shall be recorded on a Report of Nondestructive Testing. 20.2 All examination items shall be classified as acceptable or unacceptable and shall be indicated as such on the report form. 20.3 All unacceptable indications shall be marked on the examination item. 20.4 The technician performing the examination shall be responsible for interpretation of the indications and shall so indicate by placing his signature on the examination report. 20.5 A Grid Sheet Record may be used to make a scale record of the indications found. 20.5.1 Retention  MTI-014-MP DETECT TANK SERVICES, LLC Rev. 2 Revised By: DW MAGNETIC PARTICLE EXAMINATION January 31, 2015 Approved by: AA Minimum Inspection Requirements Page 15 of 21 20.5.1.1 A copy of the examination reports and accompanying data shall be kept on file for a minimum of three years. 20.6 Identification 20.6.1 When required by code, specification, drawing or customer; acceptable components shall be identified by tagging, stamping, engraving or etching. 21.0 Re-Examination 21.1 Repaired areas in the test items shall be re-examined in accordance with the original test procedure and acceptance criteria. Reports of the examination of repaired areas shall be indicated by placing a letter R or writing “Repaired” on the test report.  MTI-014-MP DETECT TANK SERVICES, LLC Rev. 2 Revised By: DW MAGNETIC PARTICLE EXAMINATION January 31, 2015 Approved by: AA Minimum Inspection Requirements Page 16 of 21 Appendix A - ASME Section VIII Division 1 1.0 Pressure Vessels 1.1 Standards for Acceptability 1.1.1 Relevant Indications 1.1.2 Only indications which have any dimension greater than 1/16 inch shall be considered relevant. 1.1.3 Any questionable or doubtful indications shall be re-examined to determine whether or not they are relevant. 1.1.4 All surfaces to be examined shall be free of: 1.1.4.1 Relevant linear indications; 1.1.4.2 Relevant rounded indications greater than 3/16 inch; 1.1.4.3 Four or more relevant rounded indications in a line separated by 1/16 inch or less, edge to edge; 1.1.5 An indication of an imperfection may be larger than the imperfection that causes it; however, the size of the indication is the basis or acceptance evaluation. 1.2 Repair requirements 1.2.1 The defect shall be removed or reduced to an imperfection of acceptable size. Whenever an imperfection is removed by chipping or grinding and subsequent repair by welding is not required, the excavated area shall be blended into the surrounding surface so as to avoid sharp notches, crevices or corners. 1.2.2 Where welding is required after removal of an imperfection, the area shall be cleaned and welding performed in accordance with a qualified welding procedure. 1.2.2.1 Treatment of Indications Believed Non-relevant: Any indication which is believed to be non-relevant shall be regarded as an imperfection unless it is shown by reexamination by the same method, or by use of other nondestructive methods and/or by surface conditioning that no unacceptable imperfection is present. 1.2.2.2 Examination of Areas From Which Imperfections Have Been Removed: After a defect is thought to have been removed and prior to making weld repairs, the area shall be examined by suitable methods to ensure it has been removed or reduced to an acceptably sized imperfection. 1.3 Reexamination of Repair Areas: After repairs have been made, the repaired area shall be blended into the surrounding surface so as to avoid sharp notches, crevices or corners and reexamined by the magnetic particle method and by all other methods of examination that were originally required for the affected area, except that, when the depth of repair is less than the radiographic sensitivity required, radiography may be omitted.  MTI-014-MP DETECT TANK SERVICES, LLC Rev. 2 Revised By: DW MAGNETIC PARTICLE EXAMINATION January 31, 2015 Approved by: AA Minimum Inspection Requirements Page 17 of 21 Appendix B - ASME B31.1 Power Piping 1.0 Standards for Acceptability 1.1 General 1.1.1 Any indication which is believed to be non-relevant shall be reexamined to verify whether or not actual defects are present. Surface conditioning may precede the reexamination. Non-relevant indications which would mask indications of defects are unacceptable. 1.1.2 Relevant indications are those which result from unacceptable mechanical discontinuities. 1.1.3 An indication of a discontinuity may be larger than the discontinuity that causes it; however, the size of the indication and not the size of the discontinuity is the basis of acceptance or rejection. 1.2 The following relevant indications are unacceptable: 1.2.1 Any cracks or linear indications; 1.2.2 Rounded indications with dimensions greater than 3/16 inch; 1.2.3 Four or more rounded indications in a line separated by 1/16 inch or less edge to edge; 1.2.4 Ten or more rounded indications in any 6 inch of surface with the major dimension of this area not to exceed 6 inch with the area taken in the most unfavorable location relative to the indications being evaluated.  MTI-014-MP DETECT TANK SERVICES, LLC Rev. 2 Revised By: DW MAGNETIC PARTICLE EXAMINATION January 31, 2015 Approved by: AA Minimum Inspection Requirements Page 18 of 21 Appendix C - Welded Steel Tanks for Oil Storage 1.0 Standards for Acceptability 1.1 Acceptance standards and removal and repair of defects shall be per section 1.1 of Appendix A.  MTI-014-MP DETECT TANK SERVICES, LLC Rev. 2 Revised By: DW MAGNETIC PARTICLE EXAMINATION January 31, 2015 Approved by: AA Minimum Inspection Requirements Page 19 of 21 Appendix D - API 1104 Welding of Pipeline and Related Facilities 1.0 Standards of Acceptability 1.1 Non-relevant indications 1.1.1 Any indication with a maximum dimension of 1/16 inch or less shall be classified as non-relevant. Any larger indication believed to be non- relevant shall be regarded as relevant until reexamined by magnetic particle or other nondestructive testing method to determine whether or not an actual discontinuity exists. The surface may be ground or otherwise conditioned before reexamination. After an indication is determined to be non-relevant, other non-relevant indications of the same type need not be reexamined. 1.1.2 Relevant indications are those caused by discontinuities. 1.2 Relevant indications shall be unacceptable when any of the following conditions exists: 1.2.1 Linear indications evaluated as crater cracks or star cracks exceeding 5/32 inch in length. 1.2.2 Linear indications are evaluated as cracks other than crater cracks or star cracks. 1.2.3 Linear indications are evaluated “as if” and exceed 1 inch in total length in any continuous 12 inch length of weld or 8 percent of the weld length, whichever is less. 1.3 Rounded Indications. For evaluation purposes, the maximum dimension of a rounded indication shall be considered its size. 1.3.1 The size of an individual pore exceeds 1/8 inch 1.3.2 The size of an individual pore exceeds 25% of the thinner of the nominal wall thicknesses joined. 1.3.3 The distribution of scattered pores exceeds the concentration permitted by Figure Dl or D2. 1.3.4 Clustered pores that occur in any pass except the finish pass shall comply with the criteria of 1.3.1 through 1.3.3 above. 1.3.5 Clustered pores that occur in the finish pass shall be unacceptable when any of the following conditions exists: 1.3.5.1 The diameter of the cluster exceeds 1/2 inch  MTI-014-MP DETECT TANK SERVICES, LLC Rev. 2 Revised By: DW MAGNETIC PARTICLE EXAMINATION January 31, 2015 Approved by: AA Minimum Inspection Requirements Page 20 of 21 1.3.5.2 The aggregate length of clustered pores in any continuous 12 inch length of weld exceeds inch 1.3.5.3 An individual pore within a cluster exceeds 1/16 inch in size. 2.0 Pipe or Fitting Discontinuities. 2.1 Laminations, arc burns, long seam discontinuities and other discontinuities in the pipe or fittings detected by magnetic particle testing shall be reported to the customer. Their disposition by repair or removal shall be as directed by the customer.  MTI-014-MP DETECT TANK SERVICES, LLC Rev. 2 Revised By: DW MAGNETIC PARTICLE EXAMINATION January 31, 2015 Approved by: AA Minimum Inspection Requirements Page 21 of 21 Appendix E AWS D1.1 Structural Welding Code — Steel 1.0 Standards of Acceptability 1.1 Welds subject to magnetic particle examination shall be evaluated on the basis of the applicable visual requirements.