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ARTICLE M-
SPECIAL REQUIREMENTS FOR FERROUS
MATERIALS
AM-200 FOR ALL PRODUCT FORMS OF
FERROUS MATERIALS
AM-200.1 General Requirements. All forms of ferrous products as permitted by AM-100 may be used subject to all test coupons and test specimens being taken at the frequency stated in the applicable materials specification, and heat treated in accordance with the requirements of AM-201 and AM-202 and to the exami- nation and impact testing requirements of this Part.
AM-200.2 Definition of Thickness. The requirements in this Article make reference to thickness. For the purpose intended, the following definitions of nominal thickness apply. (a) Plate. The thickness is the dimension of the short transverse direction. (b) Forgings. The thickness is the dimension defined as follows. (1) Hollow Forgings. The nominal thickness is measured between the inside and outside surfaces (radial thickness). (2) Disk Forgings. The nominal thickness is the axial length (axial length ≤ outside diameter). (3) Flat Ring Forgings. For axial length ≤ 2 in. (51 mm), the axial length is the nominal thickness; for axial length > 2 in. (51 mm), the radial thickness is the nominal thickness (axial length less than the radial thickness). (4) Rectangular Solid Forgings. The least rectan- gular dimension is the nominal thickness. (c) Castings. For castings of the general shapes described for forgings, the same definitions apply. For other castings, the maximum thickness between two cast coincidental surfaces is the nominal thickness.
AM-200.3 Welding Restrictions. Carbon or low alloy steel having a carbon content of more than 0.35% by heat analysis shall not be used in welded construction
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or be shaped by oxygen cutting (except as provided elsewhere in this Division).
AM-201 Procedure for Obtaining Test Specimens and Coupons AM-201.1 Plates (a) Test specimens shall be taken in accordance with the requirements of the applicable material specification, except for the provisions in (b), (c), (d), and (e) below. Unless otherwise specified, the specimens from plate may be oriented with the length of the specimen parallel to the final direction of plate rolling. (b) When the plate is heat treated with a cooling rate faster than still-air cooling from the austenitizing temperature, the specimens shall be taken in accordance with requirements of the applicable material specifica- tions and 1 t from any heat treated edge, where t is the nominal thickness of the material. (c) Where a separate test coupon is used to represent the vessel material, it shall be of sufficient size to ensure that the cooling rate of the region from which the test specimens are removed represents the cooling rate of the material at least 1 ⁄ 4 t deep and 1 t from any edge of the product. Unless cooling rates applicable to the bulk pieces or product are simulated in accordance with AM-202.1, the dimensions of the coupon shall be not less than 3 t × 3 t × t, where t is the nominal material thickness. (d) When flat heads, tubesheets, and flanges with integral hubs for butt welding are to be machined from plate, additional specimens shall be taken in the locations shown in Fig. AD-701.1. (See Appendix 20.) (e) When plate specification heat treatments are not performed by the material manufacturer, they shall be performed by, or be under the control of, the fabricator who shall then place the letter “T” following the letter “G” in the mill plate marking (see SA-20) to indicate that the heat treatments required by the material specifi-
AM-201.1 1998 SECTION VIII — DIVISION 2 AM-201.
cation have been performed. The fabricator shall also document in accordance with AF-101 that the specified heat treatment has been performed. AM-201.2 Tubular Products. Specimens shall be taken in accordance with the requirements of the applica- ble material specification. AM-201.3 Bars and Bolting Material (a) Test specimens shall be taken in accordance with the requirements of the applicable material specification, except for the provisions in AM-201.3(b). (b) Test specimens shall be at least 1 ⁄ 4 t from the outside or rolled surface and with the end of the specimen no closer than one diameter or thickness from a heat treated end. (c) For bolting, the specimens shall be taken in conformance with the applicable material specification and with the end of the specimen no closer than one diameter or thickness from a heat treated end.
AM-202.1 PART AM — MATERIAL REQUIREMENTS AM-203.
representing those products shall be cooled at a rate similar to and no faster than the main body of the product except in the case of certain forgings and castings [see AM-201.4(c) and AM-201.5(c)]. This rule shall apply for specimens taken directly from the product as well as those taken from separate test coupons representing the product. The following general tech- niques may be applied to all product forms or test coupons representing the product. (a) Any procedure may be applied which can be demonstrated to produce a cooling rate in the test specimen that matches the cooling rate of the main body of the product at the region midway between midthickness and the surface ( 1 ⁄ 4 t ) and no nearer any heat treated edge than a distance equal to the nominal thickness being cooled ( t ) within 25°F (14°C) and 20 sec at all temperatures after cooling begins from the austenitizing temperature. (b) Faster cooling rates at product edges may be compensated for by: (1) taking the test specimens at least 1 t from a quenched edge where t equals the product thickness; (2) attaching a steel pad at least 1 t wide by a partial penetration weld to the product edge where specimens are to be removed; (3) using thermal barriers or insulation at the product edge where specimens are to be removed. (c) If cooling rate data for the product and cooling rate control devices for the test specimens are available, the test specimens may be heat treated in the device to represent the product provided that the provisions of AM-202.1(a) are met. (d) When the material is clad or weld deposit over- layed by the producer prior to normalizing or accelerated cooling from the austenitizing temperature, the full thickness samples shall be clad or weld deposit over- layed before such heat treatments.
AM-203 Ultrasonic Examination
AM-203.1 Plate Material (a) Except as permitted in (b), all plate 4 in. (102 mm) and over in nominal thickness shall be ultrasonically examined in accordance with the requirements of SA-435. (b) When design rules permit credit for the thickness of cladding on plate conforming to SA-263, SA-264, and SA-265, ultrasonic examination shall be made of the base plate and the bond between the cladding and the base plate in accordance with SA-578 with acceptance criteria of S-6 of Supplementary Requirements regard- less of the thickness of the plate.
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(c) When flat heads, tubesheets, and flanges with integral hubs for butt welding are to be machined from plate, ultrasonic examinations in accordance with the requirements of Appendix 20 shall be made.
AM-203.2 Forgings. All forgings 4 in. (102 mm) and over in nominal thickness shall be examined ultra- sonically in accordance with SA-388, and the acceptance standards shall be in accordance with AM-203.2(c). Rings, flanges, and other hollow forgings shall be examined using the angle beam technique. For other forgings, the straight beam technique shall be used. (a) Reference specimens shall have the same nominal thickness, composition, and P-Number grouping as the forging to be examined in order to have substantially the same structure. (b) The method used in testing forgings shall conform to the following requirements. (1) For straight beam examination, the transducers shall be 1 in. to 1 1 ⁄ 8 in. (25 mm to 29 mm) diameter or 1 in. (25 mm) square. The nominal frequency used during examination shall be 2.25 Mc /sec unless the grain size or microstructure of the material prevents adequate ultrasonic penetration, in which case the fre- quency shall be 1 Mc /sec. The instrument shall be set so that the first back reflection is 75 6 5% of screen height when the transducer is placed on an indication- free area of the forging. (2) For angle beam examination, a 1 × 1 in. (25 mm × 25 mm) or 1 × 1 ⁄ 2 in. (25 mm × 13 mm), 45 deg. transducer shall be used at a frequency of 1 mc. Angle beam examination shall be calibrated with a notch of a depth equal to the lesser of 3 ⁄ 8 in. (10 mm) or 3% of the nominal section thickness [ 3 ⁄ 8 in. (10 mm) maximum], a length of approximately 1 in. (25 mm), and a width not greater than twice its depth. (3) All conditions, such as surface finish, ultrasonic frequency, instrument settings, type of transducer and couplant used during calibration, shall be duplicated during the actual examination. (4) Insofar as practicable, all forgings shall be examined by the straight beam wave method from two directions approximately at right angles. Hollow forgings shall be examined from one circumferential surface and from one face or surface, normal to their axes. Disk forgings shall be examined from one flat side and from the circumferential surface. Forgings requiring angle beam examination shall be examined in the circumferential direction, unless wall thickness or geometric configuration of the forging makes angle beam examination impracticable. The entire volume of material shall be examined ultrasonically at some state of manufacture, preferably after final heat treatment.
AM-203.2 1998 SECTION VIII — DIVISION 2 AM-204.
If contours of the forging preclude complete ultrasonic examination after final heat treatment, the maximum possible volume shall be examined at this stage. (c) A forging shall be unacceptable: (1) if straight beam examination results show one or more discontinuities which produce indications ac- companied by a complete loss of back reflection not associated with or attributable to the geometric configu- ration; (2) if angle beam examination results show one or more discontinuities which produce indications ex- ceeding in amplitude the indication from the calibration notch. (d) In the case of straight beam examination, the following conditions shall be reported to the purchaser for his consideration and approval prior to shipment of a forging: (1) forgings containing one or more indications with amplitudes exceeding adjacent back reflections; (2) forgings containing one or more discontinuities which produce traveling indications accompanied by reduced back reflection. (A traveling indication is de- fined as an indication which displays sweep movement of the oscilloscope screen at relatively constant ampli- tude as the transducer is moved.) (e) In the case of angle beam examination, the following conditions shall be reported to the purchaser for his consideration and approval prior to shipment of the forging: (1) indications having an amplitude exceeding 50% of the calibration notch amplitude; (2) clusters of indications located in a small area of the forging with amplitudes less than 50% of the calibration notch amplitude. [A cluster of indications is defined as three or more indications exceeding 10% of the standard calibration notch amplitude and located in any volume approximating a 2 in. (51 mm) or smaller cube.] (f) Additional nondestructive examination procedures or trepanning may be employed to resolve questions of interpretation of ultrasonic indications.
AM-204 General Toughness Requirements for All Steel Products Unless exempted by AM-213, AM-214, or AM-218, Charpy V-notch impact tests in accordance with AM- 204.1 shall be made for steel materials used for shells, heads, nozzles, and other pressure containing parts, as well as for the structural members essential to structural integrity. Toughness requirements for materials listed in Table ACS-1 are given in AM-211.1 and AM-211.2. Tough-
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TABLE AM-204. IMPACT TEST TEMPERATURE DIFFERENTIAL
Minimum Specified Temperature Difference, °F Yield Strength, ksi [Note (1)] ≤ 40 10 ≤ 55 5
55 0
NOTE: (1) Impact test temperature may be warmer than the minimum design temperature by the amount shown.
ness requirements for materials listed in Table AHA- 1 are given in AM-213. Toughness requirements for materials listed in Table AQT-1 are given in AM-310. For weld and heat affected zone toughness requirements, see Article T-2. For toughness requirements applicable to bolting, see AM-214. AM-204.1 Test Procedures (a) Impact test procedures and apparatus shall con- form to the applicable paragraphs of SA-370. (b) Unless permitted by Table AM-204.1, the impact test temperature shall not be warmer than the minimum design metal temperature [see AD-121.2(f)]. AM-204.2 Test Specimens (a) Each set of impact tests shall consist of three specimens. (b) The impact test specimens shall be of the Charpy V-notch type and shall conform in all respects to the specimen requirements of SA-370 (for Type A specimens). The standard full-size (10 mm × 10 mm) specimen, when obtainable, shall be used, except that for materials that normally have absorbed energy in excess of 180 ft-lbf (800 N) when tested using full- size specimens at the specified testing temperature, subsize (10 mm × 6.7 mm) specimens may be used in lieu of full-size specimens. However, when this option is used, the acceptance value shall be 75 ft-lbf (334 N) minimum for each specimen. (c) For material from which full-size specimens can- not be obtained, either due to the material shape or thickness, the specimens shall be either the largest possible subsize specimen obtainable or specimens of full material thickness which may be machined to remove surface irregularities [the test temperature crite- ria of AM-211.3(b) shall apply for Table ACS-1 materi- als having a specified minimum tensile strength less than 95 ksi (655 MPa) when the width along the notch is less than 80% of the material thickness]. Alternatively, such material may be reduced in thickness to produce the largest possible Charpy subsize specimen. Toughness
A
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Fig. AM-211 1998 SECTION VIII — DIVISION 2
FIG. AM-211 CHARPY V-NOTCH IMPACT TEST REQUIREMENTS FOR FULL-SIZE SPECIMENS FOR CARBON AND LOW ALLOY STEELS, HAVING A SPECIFIED MINIMUM TENSILE STRENGTH OF LESS THAN 95 ksi, LISTED IN TABLE ACS-
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Fig. AM-211.1 PART AM — MATERIAL REQUIREMENTS Fig. AM-211.
FIG. AM-211.1 ILLUSTRATION OF LATERAL EXPANSION IN A BROKEN CHARPY V-NOTCH SPECIMEN
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FIG. AM-211.2 CHARPY V-NOTCH IMPACT TEST REQUIREMENTS FOR TABLE ACS-1 MATERIALS HAVING A SPECIFIED MINIMUM TENSILE STRENGTH OF 95 ksi OR GREATER AND FOR TABLE AQT-1 MATERIALS
AM-213 PART AM — MATERIAL REQUIREMENTS AM-
Table AHA-1 for all combinations of materials and minimum design metal temperatures except as exempted by (b), (c), or (d) below, or AM-213.1. (a) Required Impact Tests When Thermal Treatments Are Performed. Impact tests are required at the colder of 70°F (21°C) or the minimum design metal temperature, whenever thermal treatments 2 within the temperature ranges listed for the following materials are applied: (1) austenitic stainless steels thermally treated be- tween 900°F and 1650°F (482°C and 900°C), except Types 304, 304L, 316, and 316L which are thermally treated at temperatures between 900°F and 1300°F (482°C and 704°C), are exempt from impact testing provided the MDMT is −20°F (−29°C) and warmer and vessel (production) impact tests of the thermally treated weld metal are performed for Category A and B joints; (2) austenitic–ferritic duplex stainless steels ther- mally treated at temperatures between 600°F and 1750°F (316°C and 954°C); (3) ferritic and martensitic chromium stainless steels thermally treated at temperatures between 800°F and 1350°F (427°C and 732°C). (b) Exemptions from Impact Testing for Base Metals and Heat Affected Zones. Impact testing is not required for Table AHA-1 base metals when the nominal thick- ness is less than 0.099 in. (2.5 mm). Impact testing is not required for the following combinations of base metals and heat affected zones (if welded) and minimum design metal temperatures (MDMTs), except as modified in (a) above. (1) For austenitic chromium–nickel stainless steels as follows: (a) Types 304, 304L, 316, 316L, 321, and 347 at MDMTs of −425°F (−254°C) and warmer; (b) those types not listed in (a) above and having a carbon content 3 not exceeding 0.10% at MDMTs of −320°F (−196°C) and warmer; (c) having a carbon content 3 exceeding 0.10% at MDMTs of −55°F (−48°C) and warmer; (d) for castings at MDMTs of −20°F (−29°C) and warmer. (2) For austenitic chromium–manganese–nickel stainless steels (200 series) as follows: (a) having a carbon content 3 not exceeding 0.10% at MDMTs of −320°F (−196°C) and warmer; (b) having a carbon content 3 exceeding 0.10% at MDMTs of −55°F (−48°C) and warmer;
(^2) Thermal treatments of materials do not include thermal cutting or welding. (^3) The value of the carbon content may be as specified by the purchaser, but must be within the limits of the material specification.
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(c) for castings at MDMTs of −20°F (−29°C) and warmer. (3) For the following steels in all product forms at MDMTs of −20°F (−29°C) and warmer: (a) austenitic–ferritic duplex steels with a nomi- nal material thickness of 3 ⁄ 8 in. (10 mm) and thinner; (b) ferritic chromium stainless steels with a nom- inal material thickness of 1 ⁄ 8 in. (3.2 mm) and thinner; (c) martensitic chromium stainless steels with a nominal material thickness of 1 ⁄ 4 in. (6 mm) and thinner. (c) Exemptions From Impact Testing for Welding Procedure Qualifications. For welding procedure quali- fications, impact testing is not required for the following combinations of weld metals and minimum design metal temperatures (MDMTs) except as modified in (a) above. (1) For austenitic chromium–nickel stainless steel base materials having a carbon content not exceeding 0.10%, welded without the addition of filler metal, at MDMTs of −155°F (−104°C) and warmer. (2) For austenitic weld metal: (a) having a carbon content not exceeding 0.10% and produced with filler metals conforming to SFA- 5.4, SFA-5.9, SFA-5.11, SFA-5.14, and SFA-5.22 at MDMTs of −155°F (−104°C) and warmer; (b) having a carbon content exceeding 0.10% and produced with filler metals conforming to SFA- 5.4, SFA-5.9, SFA-5.11, SFA-5.14, and SFA-5.22 at MDMTs of −55°F (−48°C) and warmer. (3) For the following weld metal, when the base metal of similar chemistry is exempt as stated in (b)(3) above, then the weld metal shall also be exempt at MDMTs of −20°F (−29°C) and warmer: (a) austenitic–ferritic duplex steels; (b) ferritic chromium stainless steels; (c) martensitic chromium stainless steels. (d) Required Impact Testing for Vessel (Production) Plates. For welded construction, vessel (production) impact tests in accordance with AT-203 are required if the welding procedure qualification requires impact testing unless otherwise exempted by the rules of this Division. Vessel (production) impact tests are not required for welds joining austenitic chromium–nickel or austenitic chromium–manganese–nickel stainless steels at MDMTs not colder than −320°F (−196°C) where all of the following conditions are satisfied: (1) the welding processes are limited to shielded metal arc, submerged arc, gas metal arc (GMAW and FCAW), gas tungsten arc, and plasma arc; (2) the applicable Welding Procedure Specifica- tions (WPSs) are supported by Procedure Qualification Records (PQRs) with impact testing in accordance with the requirements of AM-204 (using the acceptance
AM-213 1998 SECTION VIII — DIVISION 2 AM-218.
criteria of AM-211) at the minimum design metal temperature or colder, or when the applicable PQR is exempted from impact testing by other provisions of this Division; (3) the weld metal (produced with or without the addition of filler metal) has a carbon content not exceeding 0.10%; (4) the weld metal is produced by filler metal conforming to SFA-5.4, SFA-5.9, SFA-5.11, SFA-5.14, and SFA-5.22 as modified below. (a) Each heat and/or lot of welding consumables to be used in production welding with the shielded metal arc (SMAW) and gas metal arc (GMAW) processes shall be qualified by conducting impact tests at or below the MDMT except as exempted by (c)(2) above in accordance with Section II, Part C, SFA-5.4, A9.12. Acceptance criteria shall conform with AM-211.2. (b) Each heat of welding consumables to be used in production welding with the submerged arc (SAW) process shall be qualified by conducting impact tests with each lot and/or batch of flux at or below the MDMT except as exempted by (c)(2) above in accordance with Section II, Part C, SFA-5.4, A9.12. Acceptance criteria shall conform with AM-211.2. (c) Combining more than one welding process or more than one heat, lot, and/or batch of welding material into a single test coupon is unacceptable. Testing at or below the MDMT except as exempted by (c)(2) above may be conducted by the welding consumable manufacturer provided certified mill test reports are furnished with the consumables. (d) The following filler metals may be used without impact testing of each heat and/or lot provided that procedure qualification impact testing in accordance with Article T-2 at the minimum design metal tempera- ture or colder is performed using the same manufacturer brand and type filler metal: ENiCrFe-2; ENiCrFe-3; ENiCrMo-3; ENiCrMo-4; ENiCrMo-6; ERNiCr-3; ER- NiCrMo-3; ERNiCrMo-4; SFA-5.4, E310-15 or 16. (e) The following filler metals may be used without impact testing of each heat and/or lot provided that procedure qualification impact testing in accordance with Article T-2 at the minimum design metal tempera- ture or colder is performed: ER308L, ER316L, and ER310 used with GMAW, GTAW, or PAW processes.
AM-213.1 Exemption From Impact Testing. Impact testing of materials listed in Table AHA-1 is not required, except as modified by AM-213(a), when the coincident ratio of design stress 4 in tension to allowable tensile stress is less than 0.3.
(^4) Applied stress from pressure and nonpressure loadings, including those listed in AD-110, which result in general primary membrane tensile stress.
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AM-214 Toughness Requirements for Bolting Materials AM-214.1 For Bolting Materials Listed in Table ABM- (a) Impact tests are not required for bolting materials listed in Tables ABM-1, ABM-1.2, and ABM-1.3 when used at minimum design metal temperatures equal to or warmer than those shown in these Tables. (b) Bolting materials to be used for colder tempera- tures than those shown in Table ABM-1 shall conform to SA-320, except that the toughness criterion shall be Charpy V-notch with acceptance criteria in accordance with AM-211.
AM-214.2 For Bolting Materials Listed in Table ABM-2. Impact testing is required for ferrous bolting materials for use with flanges designed in accordance with Appendices 4, 5, and 6 (see Table ABM-2). The average for three Charpy V-notch impact specimens shall be at least 30 ft–lb (133 N), and the minimum value for any individual specimen shall be 25 ft–lb (111 N).
AM-218 Materials Exempt From Impact Tests AM-218.1 For Carbon and Low Alloy Steels, De- pendent on Design Temperature. Figure AM-218. shall be used to establish impact testing exemptions for steels listed in Table ACS-1. Unless otherwise exempted by the rules of this Division, impact testing is required for a combination of minimum design metal temperature [see AD-121.2(f)] and thickness (as defined below) which is below the curve assigned to the subject material. If a minimum design metal temperature and thickness combination is on or above the curve, impact testing is not required by the rules of this Division, except as required by Article T-2 for weld metal and heat affected zones. Components such as shells, heads, nozzles, manways, reinforcing pads, stiffening rings, flanges, tubesheets, flat cover plates, backing strips, and attachments which are essential to the structural integrity of the vessel when welded to pressure retaining components shall be treated as separate components. Each component shall be evaluated for impact test requirements based on its individual material classification, thickness as defined in (a), (b), or (c) below, and the minimum design metal temperature. The following thickness limitations apply when using Fig. AM-218.1. (a) Excluding castings, the governing thickness tg of a welded part is as follows:
A
AM-218.1 1998 SECTION VIII — DIVISION 2 AM-218.
A99 NOTES TO FIG. AM-218. A GENERAL NOTES: (a) Tabular values for this Figure are provided in Table AM-218.1. (b) Castings not listed in Notes (1) and (2) below shall be impact tested. (c) For bolting, see AM-214. (d) When no class or grade is shown in Notes (1) through (4) below, all classes or grades are indicated. (e) The following shall apply to Notes (1) through (4). (1) Cooling rates faster than those obtained by cooling in air, followed by tempering, as permitted by the material specification, are considered to be equivalent to normalizing, or normalizing and tempering, heat treatments. (2)Fine grain practice is defined as the procedures necessary to obtain a fine austenitic grain size as described in SA-20. NOTES: (1) The following materials are assigned to Curve A: (a) all carbon and low alloy steel plates, structural shapes, and bars not listed in Notes (2) through (4) below; (b) SA-216 Grades WCB and WCC, and SA-217 Grade WC6, if normalized and tempered or water quenched and tempered. (2) The following materials are assigned to Curve B: (a) SA-216 Grade WCA if normalized and tempered or water quenched and tempered; Grades WCB and WCC for thicknesses not exceeding 2 in. if produced to fine grain practice and water quenched and tempered; (b) SA-217 Grade WC9 if normalized and tempered; (c) SA-285 Grades A and B; (d) SA-414 Grade A; (e) SA-515 Grade 60; (f) SA-516 Grades 65 and 70 if not normalized; (g) SA-612 if not normalized; (h) SA-662 Grade B if not normalized; (i) except for cast steels, all materials of Curve A if produced to fine grain practice and normalized that are not listed in Notes (3) and (4) below; (j) pipe, fittings, forgings, and tubing not listed in Notes (3) and (4) below; (k) parts permitted under AM-105 even when fabricated from plate that otherwise would be assigned to a different curve. (3) The following materials are assigned to Curve C: (a) SA-182 Grades 21 and 22 if normalized and tempered; (b) SA-302 Grades C and D; (c) SA-336 Grades F21 and F22 if normalized and tempered; (d) SA-387 Grades 21 and 22 if normalized and tempered; (e) SA-516 Grades 55 and 60 if not normalized; (f) SA-533 Grades B and C; (g) SA-662 Grade A; (h) all materials listed in Note (2) above if produced to fine grain practice and normalized, and if not listed in Note (4) below. (4) The following materials are assigned to Curve D: (a) SA-203; (b) SA-508 Grade 1; (c) SA-516 if normalized; (d) SA-524 Classes 1 and 2; (e) SA-537 Classes 1, 2, and 3; (f) SA-612 if normalized; (g) SA-662 if normalized; (h) SA-738 Grade A; (i) SA-738 Grade A with Cb and V deliberately added in accordance with the provisions of the material specification, not colder than −20°F (−29°C); (j) SA-738 Grade B not colder than −20°F (−29°C).
(1) for butt joints except those in flat heads and tubesheets, the nominal thickness of the thickest welded joint [see Fig. AM-218.2, sketch (a)]; (2) for corner, fillet, or lap welded joints, including attachments as defined above, the thinner of the two parts joined; (3) for flat heads or tubesheets, the larger of (2) above or the flat component thickness divided by 4; (4) for welded assemblies comprised of more than two components (e.g., nozzle-to-shell joint with reinforc- ing pad), the governing thickness and permissible mini- mum design metal temperature of each of the individual welded joints of the assembly shall be determined, and
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the warmest of the minimum design metal temperatures shall be used as the permissible minimum design metal temperature of the welded assembly [see Fig. AM- 218.2, sketch (b)]. If the governing thickness at any welded joint exceeds 4 in. (102 mm) and the minimum design metal tempera- ture is colder than 90°F (32°C), impact tested material shall be used. (b) The governing thickness of a casting shall be its largest nominal thickness. (c) The governing thickness of flat nonwelded parts, such as bolted flanges, tubesheets, and flat heads, is the flat component thickness divided by 4.
AM-218.1 PART AM — MATERIAL REQUIREMENTS AM-218.
TABLE AM-218. TABULAR VALUES FOR FIG. AM-218.
Thickness, Curve A, Curve B, Curve C, Curve D, Thickness, Curve A, Curve B, Curve C, Curve D, in. °F °F °F °F in. °F °F °F °F 0.25 18 −20 −55 −55 2.1875 102 66 29 − 0.3125 18 −20 −55 −55 2.25 102 67 30 0 0.375 18 −20 −55 −55 2.3125 103 68 31 1 0.4375 25 −13 −40 −55 2.375 104 69 32 2 0.5 32 −7 −34 −55 2.4375 105 70 33 3
0.5625 37 −1 −26 −50 2.5 105 71 34 4 0.625 43 5 −22 −48 2.5625 106 72 35 5 0.6875 48 10 −18 −45 2.625 107 73 36 6 0.75 53 15 −15 −42 2.6875 107 74 37 7 0.8125 57 19 −12 −39 2.75 108 74 38 8
0.875 61 23 −9 −36 2.8125 108 75 39 9 0.9375 65 27 −6 −33 2.875 109 76 40 9 1.0 68 31 −3 −31 2.9375 109 77 41 10 1.0625 72 34 −1 −28 3.0 110 78 41 11 1.125 75 37 2 −26 3.0625 111 78 42 12
1.1875 77 40 2 −24 3.125 111 79 43 13 1.25 80 43 6 −22 3.1875 112 80 44 13 1.3125 82 45 8 −19 3.25 112 81 44 14 1.375 84 47 10 −18 3.3125 113 81 45 15 1.4375 86 49 12 −16 3.375 113 82 46 15
1.5 88 51 14 −14 3.4375 114 83 46 16 1.5625 90 53 16 −13 3.5 114 83 47 17 1.625 92 55 17 −11 3.5625 114 84 48 18 1.6875 93 57 19 −10 3.625 115 85 49 19 1.75 94 58 20 −8 3.6875 115 85 49 19
1.8125 96 59 22 −7 3.75 116 86 50 20 1.875 97 61 23 −6 3.8125 116 87 51 21 1.9375 98 62 24 −5 3.875 116 88 51 22 2.0 99 63 26 −4 3.9375 117 89 52 22 2.0625 100 64 27 −3 4.0 117 89 52 23 2.125 101 65 28 −...............
(d) The governing thickness of a nonwelded dished head is the greater of the flat flange thickness divided by 4 or the minimum thickness of the dished portion. (e) If the governing thickness of the nonwelded part exceeds 4 in. (102 mm) and the minimum design metal temperature is colder than 90°F (32°C), impact tested material shall be used. Examples of the governing thickness for some typical vessel details are shown in Fig. AM-218.2.
NOTE: The use of provisions in AM-204 which waive the require- ments for impact testing does not provide assurance that all test results for these materials would satisfy the impact test acceptance criteria of AM-211 if tested.
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AM-218.2 Impact Tests of Welding Procedures. For welded construction, the Welding Procedure Quali- fication shall include impact tests of welds and heat affected zones made in accordance with AM-211 when required by the following provisions. (a) Welds made with filler metal shall be impact tested in accordance with AM-211 when any of the following apply: (1) when either base metal is required to be impact tested by the rules of this Division; or (2) when joining base metals from Fig. AM-218. Curves C or D, or metals exempted from impact testing by AM-218.4(e), and the minimum design metal
A
PART AM — MATERIAL REQUIREMENTS Fig. AM-218.
FIG. AM-218.2 SOME TYPICAL VESSEL DETAILS SHOWING THE GOVERNING THICKNESSES AS DEFINED IN AM-218 (CONT’D)
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Fig. AM-218.2 1998 SECTION VIII — DIVISION 2
FIG. AM-218.2 SOME TYPICAL VESSEL DETAILS SHOWING THE GOVERNING THICKNESSES AS DEFINED IN AM-218 (CONT’D)
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Fig. AM-218.3 1998 SECTION VIII — DIVISION 2
FIG. AM-218.3 REDUCTION IN MINIMUM DESIGN TEMPERATURE WITHOUT IMPACT TESTING
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PART AM — MATERIAL REQUIREMENTS Fig. AM-218.
FIG. AM-218.4 DIAGRAM OF AM-218 RULES FOR DETERMINING LOWEST MINIMUM DESIGN METAL A TEMPERATURE (MDMT) WITHOUT IMPACT TESTING [Notes to figure follow on next page]
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