ASME SECTION VIII, DIVISION 1 INTERPRETATIONS

NOTE: THESE INTERPRETATIONS ARE FOR ASME COMMITTEE USE ONLY. THEY ARE NOT TO BE DUPLICATED OR USED FOR OTHER THAN ASME COMMITTEE BUSINESS.

WARNING: THERE ARE PROBABLY SOME TYPOGRAPHICAL ERRORS IN THIS DOCUMENT. PLEASE REVIEW THE ACTUAL INTERPRETATION FOR THE EXACT WORDING. TO GET A PRINTED COPY OF AN INTERPRETATION, FIRST HIGHLIGHT THE PORTION DESIRED, THEN GOTO File ON THE TOOLBAR, THEN Print... , THEN HIGHLIGHT THE DOT AT THE (Selection BUTTON, FINALLY PRESS THE OK BUTTON. BE CAREFUL NOT TO PRINT THE ENTIRE DOCUMENT. Interpretation: VIII-77-01 Subject: Section VIII, Division 1, U-1(c)(3) Date Issued: January 7, 1977 File: NA Question: What is the correct interpretation of Section VIII, Division 1 with regard to U-1(c)(3) as it relates-to the manufacture and stamping of compressor casings? Reply: The Scope of the present Code and the laws and regulations of some jurisdictions exclude rotating equipment under their definition of pressure vessels. The rules in Section VIII, Division 1 as presently written, may not be complete for the pressure retaining parts of such objects. If a Code "U" symbol is desired, particular attention should be given to the requirements of UG-22. It may be necessary to apply the provisions of U-2(g) or UG-101. In accordance with U-1(1) such objects may be stamped with the Code "U" symbol provided that all requirements are satisfied. Interpretation: VIII-77-02 Subject: Section VIII, Division 1, UW-51(a)(3) Date Issued: January 7, 1977 File: NA Question: With reference to UW-51(a)(3) is it permissible to qualify radiographic personnel in accordance with SNT-TC-1A by means of certification by an outside organization, such as the Canadian Government Standards Board? Reply: It is not the intent of UW-51(a)(3) to permit qualification of radiographic personnel by anyone other than the Manufacturer of the vessel involved. This would not preclude testing of radiographic personnel by an outside agency such as that which you have described as long as the vessel Manufacturer takes the final responsibility for certifying his personnel. Interpretation: VIII-77-03 Subject: Section VIII, Division 1, UNF-58 Date Issued: January 18, 1977 File: NA

Question 1: Does UNF-58(c) apply to all welded joints and vessels, including those joining nonpressure parts? Reply 1: UNF-58(c) applies to all welds in vessels or vessel parts constructed of materials conforming to the specifications listed. Question 2: Is it intended that UNF-58(c) requires that all finished surfaces of welds not required to be radiographed be examined by the liquid penetrant method? Reply 2: Affirmative. Question 3: What are the provisions of UNF-58(a) and (b) with regard to the types of joints and method of liquid penetrant examination of all finished surfaces of welds? Reply 3: It is intended that UNF-58(a) and (b) apply to all joints in vessels constructed of the materials described in those paragraphs and the method of liquid penetrant examination is such that all finished surfaces of welds are required to be examined. Interpretation: VIII-77-04 Subject: Section VIII, Division 1, UG-84(c)(5)(b), Table UG-84.1 and Table UG-84.2 Date Issued: January 18, 1977 File: NA Question: Does the following meet the intent of the Code? The material is SA-516, Grade 70 where the actual plate thickness is 0.262 in. The minimum design temperature is -50F and the Charpy impact specimen size is 10 x 5 mm. Since the specimen width (0.197) is less than 80% of the actual plate thickness, what is the interpretation with regard to the appropriate test temperature per Table UG-84.2 and with regard to the applicable Charpy V-notch impact energy in foot-pounds per Table UG-84.1. Reply: The provisions of the second sentence of UG-84(c)(5)(b) require that the test temperature for the specimen in question is that which is adjusted by Table UG-84.2 for the temperature reduction corresponding to the actual material thickness and the temperature reduction corresponding to the Charpy specimen width actually tested. In this case the test temperature would be reduced by the temperature reduction corresponding to the size of the specimen, 20F, minus the temperature reduction corresponding to the material thickness, 10F, resulting in a temperature reduction of 10F below the minimum design temperature -50F or a required test temperature of -60F. The required energy in foot-pounds from Table UG-84.1 is multiplied by 5/10 or the ratio of the actual specimen width along the notch to the width of a full size specimen. Interpretation: VIII-77-05 Subject: Section VIII, Division 1, UG-84 and Table UG-84.2 Date Issued: January 18, 1977 File: NA Question 1: Table UG-84.2 refers to width along the notch. Is this dimension limited by test plate thickness for subsize specimens? Reply 1: The "width along the notch" dimension as indicated above is limited by the test plate thickness for subsize specimens.

Question 2: In the title of Table UG-84.2 it indicates .when the subsize Charpy impact width is . . ." Is the width referred to here specifically referring to the width along the notch? Reply 2: Affirmative. Question 3: For materials of thickness less than 0.394 in., and when the width along the notch is at least 80% of the plate material being tested, is the test temperature reduced below the minimum design temperature by an amount indicated in Table UG-84.2? Reply 3: We would refer you to the first sentence of UG-84(c)(5)(b) which indicates that the Charpy tests of such a specimen shall be conducted at a temperature not warmer than the minimum design temperature. Further, there is no requirement for reducing this temperature further. Interpretation: VIII-77-06 Subject: Section VIII, Division 1, SB-111, Copper Alloy 706 Date Issued: January 18, 1977 File: NA Questions: Is light drawn tubing in accordance with SB-111, Alloy 706 acceptable for Section VIII, Division 1 vessels? Are there problems in recognizing hard drawn tubing? Replies: SB-111, Alloy 706, light drawn tubing is acceptable in Table UNF-23.2 of Section VIII, Division 1. The Summer 1976 Addenda should have reflected this in the tabulation; however, this will be corrected in the Winter 1976 Addenda in the Errata portion. With regard to hard drawn tubing, the Committee has not received a user request for this material and, therefore, has not addressed its inclusion in Section VIII, Division 1. Interpretation: VIII-77-07 Subject: Section VIII, Division 1, UG-23(b) Date Issued: January 28, 1977 File: BC75-358 Question: How should UG-23(b) be interpreted with regard to its applicability to vessels having stresses which would cause fibers to be in compression as well as in tension? Reply: For vessels whose fibers are in tension as well as in compression, the vessel designer must examine both the tension and compression sides individually to determine whether their algebraic sum or difference does not exceed the maximum allowable stress value which by the rules of UG-23(b) shall be the smaller of the value of maximum allowable stress in the tables of Subsection C or the value of factor B. Interpretation: VIII-77-08 Subject: Section VIII, Division 1, UW-11 Date Issued: February 4, 1977 File: NA Question: What is the correct interpretation of Section VIII, Division 1, UW-11(a) with regard to the applicable requirements for Category D welds such as those shown in Fig. UW-16.1?

Reply: For vessels constructed under the provisions of full radiography in UW-11, UW-11(a)(5) requires only that Category D butt welds be required to be radiographed for their full length. Such welds are shown in Fig. UW-16.1, sketches q-1, q-2, q-3, and q-4. This does not preclude the possibility of having nozzle attachments by any of the other sketches shown in Fig. UW-16.1 where radiography would not be a requirement. Interpretation: VIII-77-09 Subject: Section VIII, Division 1, Table UHA-23, Use of SA-193 B8 Class 2 Bolts at Elevated

Temperatures Date Issued: February 4, 1977 File: NA Question: May SA-193 Grade B8, Class 2 bolts be used for temperatures higher than those listed in Table UHA-23 with the same temperature and stress levels as Class 1 bolts? It is noted that at the increased temperatures the Class 2 bolts are identical to the Class 1 bolts as they lose their increased yield strength which was obtained at room temperature by strain hardening; also, that the Class 1 bolts are inadequate for initial gasket seating forces but are adequate for service loads for flange configurations. Reply: It is permissible to use the Class 2 bolts at elevated temperatures with the same temperature and stress values as listed for the Class 1 bolts for SA-193, Grade B8 as described above. Interpretation: VIII-77-10 Subject: Section VIII, Divisions 1 and 2, UG-116 and AS-131 Date Issued: February 4, 1977 File: NA Question: What is the correct interpretation as to whether, under the provisions of Section VIII, Division 1, the words "design pressure" may be used instead of "maximum allowable working pressure" on the vessel nameplate? It is noted that this is different from Section VIII, Division 2 in Fig. AS-131.1 in this respect. Reply: UG-116(a)(3) requires that the maximum allowable working pressure be stamped on the nameplate. It is permissible to supplement this information with the design pressure on the nameplate if so desired. The differences between Division 1 and Division 2 in this respect are intentional, Interpretation: VIII-77-11 Subject: Section VIII, Division 1, UG-25(a) and UG-46(f)(3) Date Issued: February 4, 1977 File: NA Question: What is the correct interpretation of Section VIII, Division 1 relative to whether it is required that an ammonia receiver manufactured to Section VIII, Division 1 have manholes in accordance with UG-46(f)(3) where they are over 36 in. I.D.? Reply: UG-25(a) indicates that the user or his designated agent has the responsibility to determine whether or not the substance contained in a vessel is corrosive and, if there is no corrosion allowance provided, this fact shall be indicated on the Manufacturer's Data Report (see U-2 for definition of "user" or designated agent"). If the substance contained in the vessel is determined as noncorrosive in accordance with above, then UG-46(a) permits the omission of inspection openings described in that paragraph.

Interpretation: VIII-77-12 Subject : Section VIII, Division 1, UG-93 and UG-11, Pipes Used as Nozzle Necks in Pressure Vessels Date Issued: February 4, 1997 File: NA Question: What is the correct interpretation of Section VIII, Division 1 as to whether pipe used as a nozzle neck in a pressure vessel would be covered under UG-11? Reply: Pipe used as a nozzle neck in a pressure vessel would not fall under the provisions of UG-11 Miscellaneous Pressure Parts, but would be procured by the vessel Manufacturer as a material and would be subject to the provisions of UG-93. Interpretation: VIII-77-13 Subject: Section VIII, Division 1, UW-13 and UG-93(d)(3) Date Issued: February 4, 1977 File: NA Question: What is the correct interpretation of UW-13(e) with regard to the liquid penetrant and magnetic particle examination which is required per UG-93(d)(3)? Reply: As defined in UG-34(b), the part designated ts is the actual thickness of the shell exclusive of corrosion allowance and the vertical (thicker) member is the forged or rolled plate whose cut edges shall be examined in accordance with UG-93(d)(3). Interpretation: VIII-77-14 Subject: Section VIII, Division 1, UCS-56 Date Issued: February 4, 1977 File: NA Question: Is it permissible under Section VIII, Division 1 to partly weld a nozzle-to-shell joint, postweld heat treat to UCS-56, and then complete the weld without further postweld heat treatment? Reply: It is not the intent of Section VIII, Division 1 to permit a weld to be only partially completed prior to postweld heat treatment as indicated in your inquiry. The thickness of the shell plate would be the controlling factor in any case under the provisions of UCS-56(d)(4). Interpretation: VIII-77-16 (Refer to II-77-06, p. 171) Subject: Section II, Part B and Section VIII, Division 1, SB-17 1, Grade CDA 706 Interpretation: VIII-77-17 Subject: Section VIII, Division 1, UG-44 Date Issued: February 7, 1977 File: NA Question: Is it permissible for a vessel manufacturer to accept an ANSI B16.5 flange for use in a Section VIII, Division 1 pressure vessel without further calculations or comparison with Appendix 2?

Reply: It is permissible for a vessel manufacturer to utilize an ANSI B16.5 flange in accordance with UG-44 without further calculation or comparison to Appendix 2. Interpretation: VIII-77-18 Subject: Section VIII, Division 1, UG-28(b) and UG-29(a) Date Issued: February 7, 1977 File: NA Question: Does the length L(2) as defined in UG-28(b) and Ls(2) as defined in UG-29(a) apply to the length between circumferential connections to the shell of a dimpled jacket? Reply: This construction would follow the rules of UW-19 which also requires that the dimpled component is rated based on a proof test given in UG-101. The flat plate (inner shell) is calculated as a braced and stayed plate. Consequently, the use of UG-28 and UG-29 would be inappropriate. Interpretation: VIII-77-19 Subject: Section VIII, Division 1, UHA-20, Minimum Thickness of Tubes in a Shell-and-Tube-

Heat Exchanger Date Issued: February 7, 1977 File: NA Question: Are the minimum thickness requirements in UHA-20 applicable to the tubes in a shell-and-tube heat exchanger? Reply: The rules of UHA-20 relative to minimum thickness are not applicable to tubes in a shell-and-tube heat exchanger provided the outer pipe or shell is constructed to the rules of Section VIII, Division 1 including the minimum thickness requirements. Interpretation: VIII-77-20 Subject: Section VIII, Division 1, UW-12(c), Stress Reduction for Unstayed Covers Date Issued: February 15, 1977 File: NA Question: Is it required that the stress S for unstayed covers in UG-34 be reduced per UW-12(c) for vessels that are neither fully radiographed nor spot radiographically examined? Reply: The stress reduction of UW-12(c) applicable to design calculations for vessels that are neither fully radiographed nor spot radiographically examined is not applicable to the stress S for unstayed flat heads and covers in UG-34. Interpretation: VIII-77-21 Subject: Section VIII, Division 1, UG-11(a) Date Issued: February 23, 1977 File: NA Question: What is the correct interpretation of Section VIII, Division 1 with regard to the applicable material certification requirements for pipe nipples not exceeding 2 in. diameter and welding caps not exceeding 5 in. diameter?

Reply: Welding caps appear to fall within the provisions of UG-11(a) and, as such, the materials shall be those permitted under Section VIII, Division 1 or in an accepted standard (such as an American National Standard) covering the particular type of pressure part. The marking required is that of the name or trademark of the Manufacturer and such other markings as are required by the standard involved, such as ANSI-B 16.9, Wrought Steel Butt Welding Fittings. Under the rules applicable through the Summer 1976 Addenda, the pipe nipples shall satisfy either: (1) UG-93(a), which requires a Certified Test Report or Certificate of Compliance as provided for in the Material Specification. (However, the requirements of UG-93 will be significantly reduced with the Winter 1976 Addenda, as indicated on the copy of the print of the applicable paragraph); or, (2) UG-11(a). However, since there is not an accepted standard covering pipe nipples, use of this alternate would require that the nipples be made of a material permitted under Section VIII, Division 1 and that the requirements concerning the part Manufacturer's marking, identification, and written listing must be satisfied. Interpretation: VIII-77-22 Subject: Section VIII, Division 1, UCS-79, Cold Working and Heat Treatment of Flanged and

Dished Heads Date Issued: February 23, 1977 File: NA Question: What is the correct interpretation of Section VIII, Division 1 with regard to the heat treatment required for a flanged and dished head which has been formed by cold working? Reply: The requirements of UCS-79 require heat treatment per UCS-56 under the provisions described. We would caution that ASTM material specification designations may not always be arbitrarily substituted for ASME designations since they are not always identical. Interpretation: VIII-77-23 Subject: Section VIII, Division 1, Scope Date Issued: March 1, 1977 File: NA Question: What is the interpretation of the Scope of Section VIII, Division 1 with regard to a vessel having an ordered inside diameter of 6.065 in. as opposed to 5.761 in.? Reply: Vessels made of 6 in. standard pipe 6.065 in. I.D. (as ordered) fall under the Scope of Section VIII, Division 1. Similarly if the ordered inside diameter is 5.761 in. this does not fall under the Scope of Section VIII, Division 1. Interpretation: VIII-77-24 Subject: Section VIII, Division 1, UCS-66 Date Issued: March 2, 1977 File: NA Question: May a material, which is acceptable for Section VIII use, be used without impact tests for an operating temperature of -20F?

Reply: UCS-66(c)(1) permits an approved material to be used at or above -20F without impact testing. Interpretation: VIII-77-25 Subject: Section VIII, Division 1, U-2(g) and UG-101 Date Issued: March 7, 1977 File: NA Question: Where complete rules for design and construction are not given, must a proof test in accordance with UG-101 always be performed or does conformance with U-2(g) permit acceptance without such testing? Reply: Proof testing in accordance with UG-101(a) is only required when the strength cannot be computed with a satisfactory assurance of accuracy. The intent of the reference to U-2 in UG-101(a)(1) is to call attention to that paragraph which permits construction to Section VIII, Division 1 when the rules do not cover all details of design and construction. U-2(g) states that where complete details are not given, it is intended that the manufacturer, subject to the approval of the Inspector, shall provide details of design and construction which will be as safe as those provided by the rules. A proof test performed in accordance with UG-101 is one method for accomplishing this. Alternative procedures, such as stress analyses which demonstrate conformance with the design criteria used to develop the specific design rules of Section VIII, Division 1, may be used subject to the approval of the Inspector. The Inspector's acceptance is indicated by his signing of the Manufacturer's Data Report. The use of U-2(g) may be noted under remarks on that form. Interpretation: VIII-77-26 Subject: Section VIII, Divisions 1 and 2, Allowable Stress Values for SA-240 Date Issued: March 14, 1977 File: BC75-630 Question 1: In Section VIII, Division 1, SA-240, TP316L is listed with a value at 400F of 15.5 ksi. Since this is the only value to change since the 1971 Edition, please verify that this value is correct. Reply 1: This will advise that the value of 15.5 is the correct value. Question 2: SA-240 TP316 is listed in Section VIII, Division 2 with a value of 17.2 ksi at 500F whereas in Section VIII, Division 1 the stress value for the same temperature is 17.9. Please advise if there is a discrepancy. Reply 2: This is to advise that the value in Section VIII, Division 2 for the subject material at 500F should be 17.9 ksi, the same as in Section VIII, Division 1. We thank you for pointing this out and this will be reflected in a future errata. Interpretation: VIII-77-27 Subject: Section VIII, Division 1, Certificate of Test for Welding Filler Metal Date Issued: March 15, 1977 File: NA Question 1: Must certified test reports be included with the purchase of SFA welding electrodes?

Reply 1: Certified test reports are not required for filler metals for Section VIII construction. Testing of specific batches of electrodes is performed at the option and expense of the purchaser. Reports may also be furnished, if requested. Question 2: Does ASME recognize certain companies for the purpose of manufacturing certified welding electrodes? Reply 2: ASME does not recognize certain companies as approved manufacturers of filler metals. Interpretation: VIII-77-28 Subject: Section VIII, Division 1, UW(a) and (b), Double Butt Weld Date Issued: March 16, 1977 File: NA Question: Must the reverse or first side of a GTAW process double butt weld be ground or prepared or the second side of the weld as described in UW-37(a) if the process produces a first side weld of radiographable quality? Reply: The reverse side of double welded joints need not be prepared as per UW-37(a) if the provisions of UW-37(b) are complied with. A properly deposited TIG weld will meet the requirements of proper fusion and penetration, as well as freedom from impurities as stated in UW-37(b). Interpretation: VIII-77-29 Subject: Section VIII, Division 1, UW-35 Date Issued: March 18, 1977 File: BC75-558 Question: Does a butt welded joint comply with UW-35 if (a) the joint has complete joint penetration and complete fusion for the full length of the weld, and is free from undercuts, overlaps, and abrupt ridges and valleys, and (b) the surface of the weld groove falls below the surface of the adjoining plate in a smooth transition and exceeds minimum design thickness requirement for the material? Reply: The rules of UW-35(a) indicate that the butt joint as described does not comply with the intent of Section VIII, Division 1. Interpretation: VIII-77-30 Subject: Section VIII, Division 1, UW-11, UW-12, Partial Radiography Date Issued: March 18, 1977 File: NA Question 1: Do the service restrictions of UW-2(a) for lethal substances and UW-2(c) for unfired steam boilers with design pressures exceeding 50 psi permit the use of partial radiography under UW-11(a)(5)(b)? Reply 1: For lethal substances, all butt welds in vessels are required to be examined radiographically for their full length as prescribed in UW-11(a)(1) except as provided in UW-11(a)(4) which permits no radiography for Categories B and C butt welds in nozzles and communicating chambers that neither exceed 10 in. nominal pipe size nor 1-1/8 in. wall thickness. Question 2: Does the term "fully radiographed" in UW-12(a) include the provisions for partial radiography under UW-11(a)(5)(b)?

Reply 2: Affirmative. Question 3: In Table UCS-57, is partial radiography permitted for butt welded joints above the nominal thicknesses listed in the table for the various P-Number and group number classifications? Reply 3: Negative. [See also UW-11(a)(2)] Question 4: Does UHA-33(b) require radiography for the full length without the use of partial radiography for the butt welded joints in vessels of the various materials listed therein? Reply 4: Affirmative. Question 5: In UHT-5(a) it refers to "complete radiographic examination" in accordance with UW-51. Does this permit the use of partial radiography under UW-11(a)(5)(b)? Reply 5: Negative. Complete radiographic examination requires this examination for 100% of the length of the weld. Interpretation: VIII-77-31 Subject: Section VIII, Division 1, UW-12(c) Date Issued: March 18, 1977 File: NA Question: Under Section VIII, Division 1, UG-31, does the 20% stress reduction in UW-12(c) for nonradiographed vessels apply to electric resistance welded pipe as shown in Table UCS-23? Reply: UW-12(c) requires that ". . in all other design calculations . . ." 80% of the allowable stress is required except as specified therein. If a vessel utilizes a resistance welded pipe as the shell of a vessel, and there are arc or gas welded butt joints that are not radiographed, the stress reduction in UW-12(c) applies. Interpretation: VIII-77-32 Subject: Section VIII, Division 1, UG-101 Date Issued: March 25, 1977 File: NA Question: May calculations be performed in lieu of proof testing to destruction to justify design conditions of half-pipe coil jackets on a pressure vessel? Reply: Refer to UG-101(a)(1). This indicates that proof tests to establish maximum allowable working pressure are intended for those vessels or vessel parts where the strength cannot be computed with a satisfactory assurance of accuracy. Therefore, if you are able to satisfy your Authorized Inspector that your calculations satisfy this requirement, then proof testing would not be required. Interpretation: VIII-77-33 Subject Section VIII, Division 1, UCS-85(b) and (d) Date Issued: March 25, 1977 File: NA

Question: Is pipe, procured in accordance to a specification in Section II for use in nozzles in a Code vessel, considered a standard pressure part under the provisions of UG-11 and exempted from the provisions of UG-85 and UCS-85(b) under UCS-85(d)? Reply: The pipe described in the question, where used in the fabrication of nozzles, would not be covered under the provisions of UCS-85(d) where reference is made to standard items described in UG-11. Therefore, this would require test specimens as described in UCS-85(b). Interpretation: VIII-77-34 Subject: Section VIII, Division 1, Use of SA-515 Material and Interpretation of UG-99 Date Issued: March 25, 1977 File: NA Question 1: Is it permissible to use SA-515, Gr. 60 material in the ranges for which allowable stresses are listed in Table UCS-23 without additional requirements in that temperature range? Reply 1: It is permissible to use SA-515, Gr. 60 material as listed in Table UCS-23 in the temperature ranges for which tabular values are listed. However, the designer of the vessel should be aware that the Code represents minimum safety requirements and that he should consider any additional design considerations that may exist for his particular application. Question 2: Is it permissible under the provisions of UG-99(h) to stipulate that the hydrostatic test shall be conducted at a temperature at or above 60F? Reply 2: The 60F limitation under UG-99(h) is a recommendation only [see also footnote 1 to subparagraph (h)]. Beyond this it is up to the vessel designer to take into account the nil ductility transition temperature for the particular materials involved. Question 3: What does the term "intermediate" mean in terms of the use of SA-515 material for specific services? Reply 3: In general, intermediate temperature service would be indicative of being at greater than room temperature but at a temperature less than that where creep considerations would be a controlling factor. Interpretation: VIII-77-35 Subject: Section VIII, Division 1, Fig. UW-13.2 Date Issued: April 22, 1977 File: NA Question: Is it permissible to use a tubesheet with a bolting flange that utilizes a weld detail similar to that shown in Fig. UW-13.2, sketch (d)? Reply: Typical joint details that are applicable for tubesheets with a bolting figure are given in Fig. UW-13.2, sketches (h) through (l). Sketch (d) is not an acceptable welding attachment with the addition of a bolting flange since the weld dimensions are not adequate for the additional moment imposed by the bolt load. Interpretation: VIII-77-36 Subject: Section VIII, Division 1, Nozzle Configuration

Date Issued: April 22, 1977 File: BC77-222 Question: In a Section VIII, Division 1 vessel, may a nozzle utilize an abrupt transition in outside diameter? Reply: A nozzle which utilizes an abrupt transition in outside diameter is not prohibited by the rules of Section VIII, Division 1 providing all of the applicable requirements are met, paying particular attention to te in UG-40 and Fig. UG-40, and complying with items such as the strength of attachment welds in UG-41 and the minimum nozzle requirements for attachment welds in UW-16. Interpretation: VIII-77-37 Subject: Section VIII, Division 1, UG-80, Out-of-Roundness Date Issued: April 22,1977 File: BC77-236 Question: Is it permissible to exceed the permissible out-of-roundness of cylindrical shells under internal pressure as required by UG-80(a) if an analysis is made as a basis? Reply: Under the rules of Section VIII, Division 1, an analysis as described in the above question is not permitted to circumvent the rules as presently written. U-2(g) permits analysis to be made for those instances where rules do not exist in Section VIII, Division 1. Interpretation: VIII-77-38 Subject: Section VIII, Division 1, Nonmandatory Appendix A Date Issued: April 25, 1977 File: BC73-467 Question 1: For welded only joints under Table UA-002 is it required that the "a" dimensions be 1.4t in the absence of testing? Reply 1: The requirement of 1.4t is not a mandatory requirement and provisions are made in the Table to accommodate other designs, for example, type "b" permits a reliability factor of 0.55 for fr (no test) for "welded only" joints t (a < 1.4t). Question 2: Is tube or tubesheet hardness taken into account for the factor "fy" in UA-002? Reply 2: Although it is recognized that hardness is a factor in tube-to-tubesheet design, it is sensitive to the fabrication process used, and consequently, hardness values are generally difficult to obtain with a degree of accuracy. For this reason, the rules in Appendix A are written to utilize data, such as yield strength values, for the factor fy. Interpretation: VIII-77-39 Subject: Section VIII, Division 1, Nonmandatory Appendix A Date Issued: April 25, 1977 File: BC73-467 Question 1: For welded only joints under Table UA-002 is it required that the "a" dimension be 1.4t in the absence of testing?

Reply 1: The requirement of 1.4t is not a mandatory requirement and provisions are made in the Table to accommodate other designs; for example, type "b" permits a reliability factor of 0.55 for fr (no test) for welded only joints t (a < 1.4t). Question 2: In Table UA-002, is rolling required to be done prior to welding? Reply 2: Regarding the rolling and welding sequence, Note 8 to Table UA-002 indicates that the sequence used in the joint description does not necessarily indicate the order in which the rolling and welding is performed. Question 3: Figure UA-002 appears to show contact fits between the tube outside diameter and the tube hole. This would seem to preclude "welded only" design. Do these sketches also represent types "a" and "b" of Table UA-002? Reply 3: Figure UA-002 is intended to be schematic only and not show all details such as grooves, fits, etc. Your point is well taken, and the Committee will continue to study this point for possible clarification. Question 4: In the revised Fig. UA-002, the joints are indicates as "some acceptable." If this Appendix is adopted as mandatory, would this limit the selections to the joints shown in the Figure? Reply 4: Whether or not the Appendix is adopted as mandatory, the joints shown in Fig. UA-002 are not intended to be all-inclusive and would not preclude other similar acceptable joints. Interpretation: VIII-77-40 Subject: Section VIII, Division 1, Nonmandatory Appendix A Date Issued: April 25, 1977 File: BC73-467 Question 1: The limits of acceptability for rolled only joints in various material combinations seem overly restrictive. We feel that these should be relaxed. Reply 1: The values for acceptability for rolled only joints are based on available published data which has been submitted to the Committee. If you have any further test results to contribute in order that consideration can be given to your request, please forward same to our attention. Question 2: The testing of tube-to-tubesheet joints is an added expense and is of little or no value where previously established proprietary designs have proven to be adequate and reliable. Should this additional testing be eliminated based on proprietary designs and experience? Reply 2: If on the basis of experience you can provide the Committee with data or any other technical basis for the elimination of additional testing as outlined in Appendix A, please forward same to our attention. Question 3: If Appendix A should become mandatory, would other designs, such as double tubesheets, be precluded? Reply 3: Should Appendix A become mandatory, other special designs beyond what is required in Appendix A would not be precluded; however, it is the responsibility of the manufacturer to review his design with his Inspector.

Interpretation: VIII-77-41 Subject: Section VIII, Division 1, Nonmandatory Appendix A Date Issued: April 25, 1977 File: BC73-467 Question 1: Is it necessary to achieve a 1.4t minimum weld size for all applications in Appendix A? Reply 1: Appendix A, as revised by the Winter 1976 Addenda to Section VIII, Division 1, gives relief for welds of less than 1.4t minimum weld size and provides for the case when the weld is less than 1.0t in Table UA-002. Question 2: For the thickness "t", as described in Question (1), on what basis is this thickness determined? Reply 2: The tube wall thickness is based on nominal dimensions which is in agreement with Code practice. For example, see Fig. UW-16.1. Interpretation: VIII-77-42 Subject: Section VIII, Division 1, Nonmandatory Appendix A Date Issued: April 25, 1977 File: BC73-467 Question: In nonmandatory Appendix A to Section VIII, Division 1, is it necessary to achieve 1.4t minimum weld size for all applications? Reply: Appendix A, as revised by the Winter 1976 Addenda to Section VIII, Division 1, gives relief for welds of less than 1.4t minimum weld size and provides for the case when the weld is less than 1.0t in Table UA-002. Interpretation: VIII-77-43 Subject: Section VIII, Division 1, Radiography of Formed Heads Date Issued: April 25, 1977 File: NA Question: For cold formed heads to be used in Section VIII, Division 1 vessels and where radiography of the weld seams in the head is required, what are the requirements for the appropriate sequence of cold forming and radiography? Reply: Section VIII, Division 1 does not contain any specific requirements pertaining to the sequence of radiography and cold forming of heads required to be radiographed. Therefore, it is up to the vessel manufacturer to use his judgment for such an application. Interpretation: VIII-77-44 Subject: Section VIII, Division 1, U-1, Classification of Sterilizers Date Issued: April 28, 1977 File: BC76-187 Question: What Code requirements apply to a sterilizer of 9 in. I.D. which generates steam for internal use only and which is heated by a strip heater mounted on the outside?

Reply: Such a sterilizer is within the scope of Section VIII, Division 1. It could be built under the provisions of U-1(j) as a "UM" vessel. The sterilizer is not an unfired steam boiler or a fired pressure vessel, so the requirements of UW-2(c) or (d) are not mandatory. However, we caution you that the laws at the point of installation may dictate the construction. As indicated by footnote 1 to U-1, Scope, such laws must be reviewed to determine requirements that may be different or more restrictive than the Code rules. Interpretation: VIII-77-45 Subject: Section VIII, Division 1, U-1, Classification of Autoclaves Date Issued: April 28, 1977 File: BC76-187 Question: What Code requirements apply to an autoclave of 6 in. I.D. which generates steam for internal use only and which is heated by a strip heater mounted on the outside? Reply: Such an autoclave is not within the scope of Section VIII, Division 1 when the inside diameter does not exceed 6 in. [See U-1(c)(9)]. However, if desired, such an autoclave could be constructed in accordance with Section VIII, Division 1 rules [See U-1(i)]. The mandatory rules are not influenced by the location of the heater. The autoclave is not an unfired steam boiler or a fired pressure vessel, so the requirements of UW-2(c) or (d) are not mandatory. However, we caution you that the laws at the point of installation may dictate the construction. As indicated by footnote to U-1, Scope, such laws must be reviewed to determine requirements that may be different or more restrictive than the Code rules. Interpretation: VIII-77-46 Subject: Section VIII, Division 1, U-1, Classification of Autoclaves Date Issued: April 28, 1977 File: BC76-518 Question: What is the applicable Code symbol to be applied to an autoclave which uses an electric resistance heater to generate steam at no greater than 15 psig MAWP? (We assume that the steam is not for use external to the autoclave and that the heaters transmit heat directly to the water and not through the shell of the autoclave.) Reply: Such an autoclave is not within the scope of Section VIII, Division 1 when the pressure does not exceed 15 psig [See U-1(c)(8)]. However, if desired, such an autoclave could be constructed in accordance with Section VIII, Division 1 rules [See U-1(i)] . The autoclave is not an unfired steam boiler or a fired pressure vessel, so the requirements of UW-2(c) or (d) are not mandatory. However, we caution you that the laws at the point of installation may dictate the construction. As indicated by footnote 1 to U-1, Scope, such laws must be reviewed to determine requirements that may be different or more restrictive than the Code rules. Interpretation: VIII-77-47 Subject: Section VIII, Division 1, UG-80(a) Date Issued: April 29, 1977 File: BC77-262 Question: Are there any out-of-roundness tolerances for cylindrical shells subject to internal pressure other than those found in UG-80(a) for Section VIII, Division 1 construction?

Reply: The requirements of UG-80(a) are the only permissible out-of-roundness tolerances for cylindrical shells under internal pressure. Interpretation: VIII-77-48 Subject: Section VIII, Division 1, UA-6(b)(4), Dished Covers Date Issued: April 29, 1977 File: BC77-94 Question: What is the appropriate sign convention to be used for "F" and "J" in UA-6(b)(4) and Fig. UA-6(d)? Reply: Positive values for both "F" and "J" are used in the flange thickness equation of UA-6(b)(4)(b). This is caused by the value of "P" (see UG-98) and "MO" (see UA-50 and UA-55) used in the equations always being positive values because they are actually the absolute values of the calculated values for "P" and "MO". Of course, the calculated value of "MO" according to UA-6(a), could be either positive or negative depending on the assumed sign convention. The reason for this use of "P" and "MO" is that at some point on the ring cross-section, the Stresses caused by "P" and "MO" add whether the pressure is internal or external. Interpretation: VIII-77-49 Subject: Section VIII, Division 1, Date of Compliance Date Issued: April 29, 1977 File: BC77-237 Question: What determines the mandatory Code requirements to be used for the manufacture of new pressure vessels? Reply: The Foreword of Section VIII, Division 1 states that "After Code revisions are approved by Council they may be used beginning with the date of issuance shown on the Addenda. Revisions become mandatory as minimum requirements six months after such date of issuance, except for boilers or pressure vessels contracted for prior to the end of the six-month period." The applicable Code Edition and Addenda is to be recorded on the Manufacturer's Data Report. For example, see Item 5 of the U-1 Form. Interpretation: VIII-77-50 Subject: Section VIII, Division 1, UG-34, Nomenclature Date Issued: May 20, 1977 File: NA Question: In the Winter 1976 Addenda the value of E as defined in the nomenclature for unstayed flat heads and covers is as follows: E = joint efficiency, from Table UW-12, of any Category A weld as defined in UW-3(a)(1) Does this joint efficiency pertain to the efficiency of a welded joint within the head as would be present in a flat head fabricated from two or more pieces, or is this joint efficiency applicable to any Category A joint within the vessel?

Reply: The value of E as indicated above pertains to the joint efficiency to be used in a Category A butt weld in the flat head or cover and not to any Category A joint in the vessel [see also UW-3(a)(1)] Interpretation: VIII-77-51 Subject: Section VIII, Division 1, UG-15 Date Issued: May 27,1977 File: BC76-735 Question: May tubes conforming to the chemical and physical properties, heat treating, and melting requirements of SA-249, Grades TP304N and TP316N, but otherwise conforming to the manufacturing procedures, tolerances, test, and marking requirements of SA-688 be used under Section VIII, Division 1 construction? Reply: Yes. Such material may be used under the provisions of UG-15 of Section VIII, Division 1. Interpretation: VIII-77-52 Subject: Section VIII, Division 1, UW-52 Date Issued: May 27, 1977 File: BC77-241 Question: Does a weld "coupon," consisting of two plates tack welded to the end of a vessel and duplicating the longitudinal joint in that vessel for purposes of spot radiography, meet the intent of UW-52(b)(1)? Reply: UW-52(b)(1) permits one spot examination to represent identical vessels, individually of less than 50 ft seam length under certain circumstances. The "coupon" described in the inquiry does not meet the intent of UW-52(b)(1) in this regard. Interpretation: VIII-77-53 Subject: Section VIII, Division 1, UW-40 Date Issued: May 27, 1977 File: BC77-265 Question: Why is the circumferential band for local postweld heat treatment considerably larger under the provisions of UW-40(a)(5) for attachment welds than that shown under UW-40(a)(3) for circumferential butt joints? Reply: The requirement for the wider circumferential band is based on the need for assuring that the nozzle and nozzle welds, being of a different geometry than the vessel shell, are able to reach the specified heat treating temperature. This temperature is then maintained for a sufficient length of time to achieve the appropriate stress relieving effect. Interpretation: VIII-77-54 Subject: Section VIII, Division 1, UW-16 Date Issued: May 27,1977 File: BC77-274

Question: When an integrally reinforced nozzle is inserted into a shell utilizing a full penetration weld and cover weld in accordance with Fig. UW-16.1, sketch (g), what determines the dimensions of the cover weld? Reply: The dimensions of the cover weld, in the above described attachment, shall be determined in accordance with Fig. UW-16.1, sketch (g) as described in the nomenclature for tc in UW-16(b). Interpretation: VIII-77-55 Subject: Section VIII, Division 1, Fig. UA-51 Date Issued: June 21, 1977 File: BC77-255 Question: Under the provisions of Fig. UA-51.1, the values of T, U, Y, and Z pertain to the design of flanges where Poisson's ratio is assumed to be 0.30. What are the values of T, U, Y, and Z to be used in flange construction under Section VIII, Division 1 where Poisson's ratio is other than 0.30? Reply: For the design of flanges where Poisson's ratio is other than 0.30, we would direct you to the provisions of U-2(g). This covers the instance where a particular aspect of vessel design and construction is not covered by the rules of Section VIII, Division 1. Interpretation: VIII-77-56 Subject: Section VIII, Division 1, UW-5 1, Retention of Radiographs Date Issued: June 23, 1977 File: BC77-282 Question: Under the provisions of UW-51(a)(2), is it required that radiographs which were judged unacceptable by the Inspector be retained? Reply: No. Only those radiographs which represent the final acceptable vessel welds are required to be retained by the provisions of UW-51(a)(2) for a period of at least 5 years. Interpretation: VIII-77-57 Subject: Section VIII, Division 1, UG-27 Date Issued: June 23, 1977 File: BC77-342 Question: May a defect on a Section VIII, Division 1 vessel shell be repaired by grinding to a point below the required thickness of the vessel if an analysis is performed in accordance with Section VIII, Division 2? Reply: The rules prescribed in Section VIII, Division 1, UG-27 require that the thickness of the vessel be no less than that computed by the formulas given in that paragraph. Therefore, repair by grinding which causes the thickness to be less than that required by the rules of UG-27 is unacceptable. Interpretation: VIII-77-58 Subject: Section VIII, Division 1, UG-99 Date Issued: June 23, 1977 File: BC77-296

Question: Is it permissible under the rules of Section VIII, Division 1 to apply an epoxy enamel prior to the hydrostatic test of a completed vessel in accordance with UG-99? Reply: The rules of Section VIII, Division 1 do not include rules covering epoxy enamel coatings; however, application prior to hydrostatic test of a cast iron pressure vessel is not prohibited. This intent has been established by the rules given in UG-99(l) and (m) for galvanized and lead lined vessels. Interpretation: VIII-77-59 Subject: Section VIII, Division 1, Impact Testing for Carbon Steel Vessels Date Issued: June 27, 1977 File: BC77-294 Question: What are the requirements for impact testing for carbon steel vessels such as those manufactured of SA-515 or SA-455 material? Reply: We would refer you to the requirements of UCS-66 for the requirements for impact testing of materials conforming to the specifications tabulated in Table UCS-23, such as SA-515 and SA-455. This paragraph has impact test requirements for temperatures below -20F. Interpretation: VIII-77-60 Subject: Section VIII, Division 1, UW-9(c) and UW-13(a) Date Issued: June 27, 1977 File: BC77-321 Question 1: What is the intent of UW-9(c) with regard to the provision of a tapered transition for sections of different thickness? Reply 1: The intent of UW-9(c) is that a tapered transition shall be provided in accordance with Fig. UW-9 when the difference in thickness between the two sections is greater than 1/4 the thickness of the thinner section or 1/8 in., whichever is less. Question 2: In UW-13(a)(2),a tapered transition having a length not less than 3 times the offset is described for head to shell joints as shown in Fig. UW-13.1. Is this offset obtained in a similar manner as the dimension Y in Fig. UW-9? Reply 2: Yes. Interpretation: VIII-77-61 Subject: Section VIII, Division 1, Case 1292-10 and U-2(d) Date Issued: June 27, 1977 File: BC77-314 Question: In Case 1292-10, should the calculations for the plain plate used in an embossed or dimpled assembly meet the requirements for braced and stayed surfaces? Reply: The plain plate indicated in paragraph (1)(b) of the reply of Case 1292-10 shall meet the requirements for braced and stayed surfaces in UG-47 and for welded stayed construction in UW-19. The allowable working pressure for resistance welded embossed or dimpled assemblies in Case 1292-10 shall be established by the weaker of that calculated value or a proof test in accordance with paragraph (1)(a) of the reply.

Interpretation: VIII-77-62 Subject: Section VIII, Division 1, UW-11(a)(4) and UW-2(a) Date Issued: June 27, 1977 File: BC77-350 Question: Do the provisions of UW-11(a)(4) override the requirements of UW-2(a) for the exemption of certain butt welds in nozzles where a vessel is in lethal service? Reply: It is the intent of Section VIII, Division 1 that Category B and C butt welds in nozzles and communicating chambers that neither exceed 10 in. nominal pipe size or 1-1/8 wall thickness are excluded from the provisions of radiography, even though the vessel is in lethal service. This overrides the provisions of UW-2(a). Interpretation: VIII-77-63 Subject: Section VIII, Division 1, UG-116 Date Issued: June 28, 1977 File: BC77-335 Question: Is it permissible under the provisions of UG-116 of Section VIII, Division 1 to express the units of pressure and temperature in metric units on the nameplate? Reply: It is intended that the units on the nameplate be expressed in the customary English units, and if metric units are needed, these can be inserted parenthetically next to the appropriate English unit. Interpretation: VIII-77-64 Subject: Section VIII, Division 1; UW-11 Date Issued: July 1, 1977 File: BC77-295 Question: Does UW-11(a)(4) permit Category B and C butt welds to be nonradiographed under the following circumstances of nominal pipe size and wall thickness? Circumferential welded butt joints in nozzles and communicating chambers, not exceeding 10 in. nominal pipe size, need not be radiographed, only if the wall thickness does not exceed 1-1/8 in. Circumferential welded butt joints in nozzles and communicating chambers, not exceeding 1-1/8 in. wall thickness, need not be radiographed only if the nominal pipe size does not exceed 10 in. Reply: Yes. Interpretation: VIII-77-65 Subject: Section VIII, Division 1; Nonmandatory Appendix A Date Issued: July 1, 1977 File: BC77-315 Question: Note (5) to Table UA-002 in Nonmandatory Appendix A defines the term t as the nominal thickness of the average wall tube. Why is this defined as nominal t rather than required t? Reply: The Code assumes that the nominal t is to be used as the required t since the thickness is based on the worst condition, that is, all of the components are designed on the basis of the balanced strength

rather than an individual component on the basis of minimum strength. This is consistent with the philosophy set forth in the other rules of Section VIII, Division 1 such as that of UW-16 regarding requirements for attachment welds. Interpretation: VIII-77-66 Subject: Section VIII, Division 1; Appendix II, Fig. UA-48, sketch (1a) Date Issued: July 8, 1977 File: BC77-325 Question: The note under Fig. UA-48, sketch (la) indicates "this weld may be machined to a corner radius to suit standard lap joint flanges". There is a minimum dimension of 0.7c for the fillet weld in this figure. Is it the intent that the 0.7c dimension apply prior to the machining of the corner radius indicated in the note, that is, where this machining will cause the dimension of the fillet weld to be less than the 0.7c? Reply: Yes. Interpretation: VIII-77-67 Subject: Section VIII, Division 1; UCL-36(b) Date Issued: July 8, 1977 File: BC77-323 Question: Under the provisions of UCL-36(b) and UW-52(a), are the welds in a vessel of a Specification SA-264, designed for external pressure and welded with austenitic chromium-nickel steel filler metal, required to be spot radiographed? Reply: The provisions of UCL-36(b) are applicable to chrome alloy cladding which has a quality of air hardening and, as such, would not be applicable to SA-264 which is a chrome nickel high alloy non-air hardening cladding. Therefore, such a vessel welded with austenitic chromium nickel steel filler metal would not be required to be spot examined per UCL-36(b). Interpretation: VIII-77-68 Subject: Section VIII, Division 1; UG-101(d) Date Issued: July 8, 1977 File: BC77-324 Question: Is it permissible under Section VIII, Division 1 that different casting materials used to make heads of the same design and pressure rating may be proof tested by an individual proof test for the various materials involved? Reply: It is the intent of UG-101(d) that when different materials such as brass, stainless steel, and cast iron are used to make parts for a particular design and pressure rating, individual proof tests shall be carried out for each material used. Interpretation: VIII-77-69 Subject: Section VIII, Division 1; UCS-79(b) Date Issued: July 11, 1977 File: BC77-312

Question 1: Is dimpled construction made by a method where the dimples are punched and drawn cold in a hydraulic actuated die set, permissible under UCS-79(b) of Section VIII, Division 1? Reply 1: UCS-79(b) prohibits carbon and low alloy steel plates from being formed cold by blows. The construction described in the question is not considered an operation of this type but more of a pressing operation and therefore, is permissible under the provisions of Section VIII, Division 1. Question 2: Is proof testing in accordance with UG-101 required for a dimpled construction described in Question 1? Reply 2: Yes. Refer to UW-19(c)(2). As a matter of interest, there are three Code Cases which cover dimpled construction for resistance welding, gas metal arc spot welding, and resistance welded hydraulically formed panels. These are Cases 1292-10, 1376-8, and 1585-1, respectively. Interpretation: VIII-77-70 Subject: Section VIII, Division 1; UG-10 and Method of Rolling Plate for a Shell of a Vessel Date Issued: August 8, 1977 File: BC77-343 Question 1: If a Material Manufacturer furnishes a plate to a Manufacturer of a vessel for Section VIII, Division 1 Construction, and the plate has been sufficiently marked to identify the specification number, is it necessary that the requirements of UG-10 be carried out for "Materials not fully identified" if the Material Test Report or Certificate of Compliance has not been furnished? Reply 1: If a material has been furnished in accordance with the above without the necessary documentation, such as a Certified Material Test Report or Certificate of Compliance, it is only necessary that the vessel Manufacturer obtain this documentation from the Material Manufacturer under the guidance of his Authorized Inspector. Alternatively, the material might be qualified under the provisions of UG-10. Question 2: Is there any restriction in Section VIII, Division 1 as to whether a plate to be used in the shell of the vessel must be rolled in the same direction as the shell is to be rolled? Reply 2: No. Interpretation: VIII-77-72 Subject: Section VIII, Division 1; UG-25(d) and UCS-25 Date Issued: August 12, 1977 File: BC76-614 Question: What is the intent of Section VIII, Division 1 with regard to the corrosion allowance required by UG-24 and UCS-25 relative to an air-oil separator reservoir manufactured for a rotary screw air compressor. The vessel contains both air and oil. Does the term "compressed air" in UCS-25 apply? Reply: The present wording of UCS-25 of Section VIII, Division 1 does not exempt vessels with a required minimum thickness of 1/4 in., or less that are to be used, in compressed air service, or containing compressed air and oil, from the corrosion allowance provision of this paragraph, unless the following conditions are met: (1) The vessels are designed in accordance with UW-12(c) of the Code; or (2) The compressed air has had moisture removed to the degree that it has an atmospheric dew point of -50F.

Interpretation: VIII-77-73 Subject: Section VIII, Division 1; UG-84(i)(3), Impact Test Requirements Date Issued: August 16, 1977 File: BC77-338 Question 1: This concerns a single vessel requiring more than 400 ft of welding per weld procedure and which has a wall thickness varying from 3/4 in. to 2 in. All welding will be done in the 1G position and the welding is limited to joints of Categories A and B. Under the provisions of UG-84(i)(3)(a), is one production impact test plate per weld procedure all that is required for a single vessel regardless of the length of welding involved and variations in wall thickness? Reply 1: Yes. Question 2: UG-84(i)(3)(b) requires that for several vessels or parts of vessels welded within any 3 month period at one location, one test plate shall be made for each 400 ft of joints welded by the same procedure provided the plate thickness does not vary by more than 1/4 in. or 25% and the same specification and grade of material is used. Does this paragraph apply to a single vessel, either from the aspect of the thickness limitation or the length of welded joints welded by the same procedure? Reply 2: No. Interpretation: VIII-77-74 Subject: Section VIII, Division 1; UA-280 Date Issued: August 16, 1977 File: BC75-760 Question 1: In UA-280, what is the origin of the 0.7 factor applied to the allowable tensile stress in the nozzle wall shear calculation? Reply 1: The 0.7 factor is given in UG-45(b). The derivation of this factor can be found in earlier Editions of the Code. The allowable stress in shear is taken as 80% of the allowable tensile stress and a factor of 87.5% is applied for combined end and side loading. Therefore: 0.80 X 0.875 = 0.70 Question 2: In UA-280, in the calculation of (A) fillet weld shear why is (divided by 2 in this equation? It appears that only 1/2 of the weld circumference is considered. Reply 2: The example is intended to follow the rules given UG-41(c) and in particular the sentence: "The strength of the attachment joint shall be considered for its entire length of each side of the plane of the area of reinforcement defined in UG-40." This length, in Example 1 of UA-280, is "/2 X nozzle O.D." The basis concept is that the forces in the vessel from one side of the plane must be transmitted through the attachment joint and back to the vessel on the other side of the plane. Question 3: In UA-280, in the calculation for (C) groove weld tension, why is tension considered in the groove weld rather than shear? Unless the vessel is externally pressurized it would appear that the principal loading of the weld is in the shear. Reply 3: Conceptually, the vessel shell in the above example is trying to pull away from the nozzle, thereby placing tension on the groove weld. Interpretation: VIII-77-75

Subject: Section VIII, Division 1; UG-39, UG-40. Section VIII, Division 2; AD-540.1 Date Issued: August 17, 1977 File: BC77-362 Question 1: In Section VIII, Divisions 1 and 2 what are the applicable paragraphs for the limits of reinforcement for openings and flat heads? Reply 1: UG-40 of Section VIII, Division 1 and AD-540 in Section VIII, Division 2 are the applicable paragraphs for such openings. Question 2: Under what conditions would a single opening in a Section VIII, Division 1vessel not require reinforcement? Reply 2: Refer to UG-36(c)(3) which outlines the conditions under which a single opening in a vessel not subject to rapid fluctuations in pressure would not require reinforcement. Question 3: UG-39(b) and UG-39(d) give different methods of providing for the total cross sectional area of reinforcement in flat heads. Which is the required calculation? Reply 3: The vessel designer has the option of using either UG-39(b) or (d) for such a calculation, depending on which is most advantageous to him. Interpretation: VIII-77-76 Subject: Section VIII, Division 1; UW-2 Date Issued: August 25, 1977 File: BC77-398 Question: What are the specific substances considered lethal under the service restrictions of UW-2 of Section VIII, Division 1? Reply: Section VIII, Division 1 provides a definition of lethal substance in the footnotes of UW-2. A list of lethal substances is not provided since the responsibility for the determination of whether a substance is lethal as defined by Section VIII, Division 1 rests with the user and/or his designated agent. If such a substance is determined as lethal, the vessel Manufacturer shall be advised. Interpretation: VIII-77-77 Subject: Section VIII, Division 1; UW-51 Date Issued: August 25, 1977 File: BC77-395 Question: Will the issue of the 1977 Edition of Section VIII, Division 1 affect the qualification of Level III Radiographers qualified under the provisions of UW-51 by a Manufacturer's written statement based on experience? Reply: No. Interpretation: VIII-77-78 Subject: Section VIII, Division 1; Impact Tests of Weld Metals Date Issued: August 30, 1977 File: BC77-475

Question: Are impact tests required for weldments made with carbon steel base metal and E6013 electrodes below -20F? Reply: The requirements for impact testing of weldments are given in UCS-66 and particularly in UG-84. Interpretation: VIII-77-79 Subject: Section VIII, Division 1; Material Certification Date Issued: August 31, 1977 File: BC77-401 Question: Is it permissible for a vessel Manufacturer to certify, with evidence acceptable to the Authorized Inspector, that a material he has purchased complies with an ASME material specification acceptable for a vessel constructed under Section VIII, Division 1? Reply: Yes, provided that the documentation including any supplementary work performed by the vessel Manufacturer is available to the Authorized Inspector at the site or plant where the material it covers is to be used by the vessel Manufacturer in Code construction. Interpretation: VIII-77-80 Subject: Section VIII, Division 1; UW-12 and UG-36 Date Issued: August 30, 1977 File: BC77-394 Question 1: In a vessel which has satisfied the requirements of UW-52 for spot radiography and where it is desired to utilize a joint efficiency of 1.0 for the longitudinal seam in a two piece head, is it necessary to radiograph the weld attaching the head to the shell along its entire length? Reply 1: The provisions of UW-11(a)(5)(b) permit the use of partial radiography as described therein for the use of column (a) of Table UW-12 for the joint efficiency involved. Assuming in this case that the weld joint is Type No. 1, the joint efficiency would be 1.0. Question 2: If the half apex angle of a reducer or cone is 30 deg., is it necessary to provide a reinforcing ring in accordance with UG-36? Reply 2: In accordance with UA-5(e), cone to cylinder junctions without a knuckle may be used without reinforcing rings provided the design is based on a special analysis as described in that paragraph. Interpretation: VIII-77-81 Subject: Section VIII, Division 1; Manufacturer's Data Report Certification Date Issued: September 6, 1977 File: BC77-446 Question: What is the intent of the date of inspection on the Manufacturer's Data Report Form in the "Certificate of Shop Inspection" block for a Section VIII, Division 1 pressure vessel? Reply: The significance of the date as described in the question is that of the final inspection date for the completed vessel. We are of the opinion that the intent of the Code as described above is sufficiently clear not to warrant further revision.

Interpretation: VIII-77-82 Subject: Section VIII, Division 1; U-1 Manufacturer's Data Report Date Issued: September 7, 1977 File: BC77-495 Question: May the U-1 Data Report Forms existing prior to the issuance of the Winter 1976 Addenda to the 1974 Edition of Section VIII, Division 1 be used after July 1, 1977 for Code vessels? Reply: Data Report Forms which are of the format and content of those existing prior to the Winter 1976 Addenda to Section VIII, Division 1 may be used after July 1, 1977 only for vessels contracted for prior to July 1st, 1977. Interpretation: VIII-77-84 Subject: Section VIII, Division 1, Sequence of Radiography and Postweld Heat Treatment; Section

V, Required Penetrameters Date Issued: September 20, 1977 File: BC77-419 Question 1: What is the intent of Section VIII, Division 1 with regard to the sequence of postweld heat treatment and radiography? Reply 1: Section VIII, Division 1 does not require a particular sequence of radiography and postweld heat treatment except for straight chromium ferritic steels in UHA-33(b); however, the vessel designer should examine the properties of the materials involved to determine whether or not radiography would be necessary after postweld heat treatment. Question 2: For radiographic examination in accordance with Section V, what are the requirements for the manufacture of penetrameters? Reply 2: Current requirements of Section V, Article 2, T-262.1 only recognize SE-142 as an acceptable IQI design. At this time we know of no accepted method for comparing the sensitivities obtained by the two types of IQI. Interpretation: VIII-77-85 Subject: Section VIII, Division 1; Postweld Heat Treatment of Tube-to-Tubesheet Joints Date Issued: September 20, 1977 File: BC77-461 Question: Under what conditions may the postweld heat treatment be eliminated for tube-to-tubesheet welds for a fixed tubesheet heat exchanger for a P No.-1 material designed for temperatures below -20F used for Section VIII, Division 1 construction? Reply: The exemptions from postweld heat treatment under the above conditions are contained in UCS-66(c) and UCS-67(c). Interpretation: VIII-77-86 Subject: Section VIII, Division 1, UG-11 and Section I, PG-11 vs Section III Date Issued: September 23, 1977

File: BC77-368 Question: For welded parts (fittings), Section II Specifications SA-234, SA-403, and SA-420 include requirements for Code Stamping, Data Reports, Inspection, and mill test reports. These requirements appear to conflict with the provisions of PG-11.3 and UG-11(c) of Section I and Section VIII, Division 1, respectively. Are these specifications intended for Section I or Section VIII, Division 1 construction? Reply: Specifications SA-234, SA-403, and SA-420 are intended for Section III construction. Section I and Section VIII, Division 1 use of parts in accordance with these Specifications is possible provided that the base material is permitted under Section I and Section VIII rules and is so identified on the Manufacturer's Partial Data Report. However, under the provisions of PG-11.3 and UG-11(c) the corresponding ASTM material specification could be used since they are listed in an accepted standard such as ANSI B16.9. Interpretation: VIII-77-87 Subject: Section VIII, Division 1; Requirements for Relief Devices, UG-125(h) Date Issued: September 23, 1977 File: BC77-397 Question 1 and Reply 1: See Interpretation VIII-77-89, Question 1 and Reply 1. Question 2: What rules apply to the set pressure and accumulation pressure for the facilities described in Question 1? Reply 2: The requirements concerning set pressures are defined in UG-134. The relief devices must be sized to satisfy the accumulation pressure requirements of UG-125(c) or UG-125(c)(1). Question 3: May control systems or instruments be substituted for the relief device described under Question 1? Reply 3: As stated in the Note under UG-125(h), such substitution is not permitted under the present rules. Interpretation: VIII-77-88 Subject: Section VIII, Division 1; UG-129(c) Date Issued: September 27, 1977 File: BC77-337 Question: Do the rules of UG-129(c) permit the additional required marking to be placed on the rupture disk holder instead of the pressure relief valve? Reply 1: No. Question 2: Who is the "responsible manufacturer" referred to in UG-129(c)(2)? Reply 2: The responsible manufacturer is the manufacturer who conducts the certification of capacity tests of UG-127(a)(3)(b)(3). Interpretation: VIII-77-89 Subject: Section VIII, Division 1; Requirements for Relief Devices

Date Issued: September 30, 1977 File: BC76-523 Question 1: Where the only source of overpressure is external to a pressure vessel and there is no risk of exposure to fire or other source of external heat, does UG-125(h) permit a suitably set and sized relief device to be installed between the source of external pressure and the vessel rather than directly on the vessel? Reply 1: Yes Question 2: May intervening stop valves be installed between the relief device of Question 1 and the pressure vessel? Reply 2: In accordance with the provisions of UG-135(e)(2) and UA-354(b), such stop valves are permitted subject to the acceptance by the legal jurisdiction as stated in UA-350. Question 3: If a vessel has a source of overpressure internal to itself and was protected against that source by a suitable set and sized relief device installed directly on the vessel, could the vessel be protected against an external source of overpressure by another relief device installed as in Questions 1 and 2? Reply 3: Yes, subject to the qualifying conditions regarding the stop valves given in Reply 2. Question 4: If a manufacturer furnished to a user an assembly consisting of pressure vessels, piping, stop valves, and instruments to perform a specific function such as removing moisture from a gas, who is responsible for furnishing the relief devices under Questions 1, 2, and 3? Reply 4: This is a contractual matter that probably cannot be resolved by reference to Code rules. To assist in resolution of this question additional rules which may have some bearing are as follows: (a) U-2(a) which defines certain responsibilities of the user or his designated agent. (b) Footnote 2 to U-2(a) which appears to define designated agent so as to apply the manufacturer of the assembly in Question 4. (c) Footnote 31 to UG-125(a) which states, "Safety devices need not be provided by the vessel manufacturer, but overpressure protection shall be provided prior to placing the vessel in service." In the absence of any specific contractual reference to relief devices, it is our opinion that the rules would intend, under the provisions of Footnote 2 of U-2(a), that the manufacturer of the assembly would be responsible to furnish the relief device installed directly on the vessel under Question 3. Beyond this opinion, it is not believed that the Code rules can assist in this contractual matter. Interpretation: VIII-77-90 Subject: Section VIII, Division 1; Size and Volume Limits, U-1 Date Issued: September 30, 1977 File: BC76-615 Question 1: U-1(j) of Section VIII, Division 1 defines the volume and pressure limits for vessels which may be marked with a "UM" symbol. U-1(j)(2) defines 1-1/2 cu ft in volume and 600 psi design pressure as one of these limits. How is the 1-1/2 cu ft volume determined for the shell side of a shell and tube heat exchanger? Reply 1: Where the tube side is an independent pressure chamber as described in UG-19(a), the volume of the shell side of a shell and tube heat exchanger is the total shell volume minus the volume taken up by the tube side.

Where the shell can be thoroughly vented, filled, and drained, measuring a suitable liquid drained from a filled shell is a method frequently used to prove the volume of an independent chamber. Question 2: U-1(c)(9) excludes "vessels having an inside diameter not exceeding 6 in. (152 mm) with no limitation on pressure" from the scope of Section VIII, Division 1. Would this exclusion apply to a vessel in which two cylindrical shells having inside diameters less than 6 in. are connected by a pressure containing header (housing) which has an inside dimension exceeding 6 in.? Reply 2: No. Interpretation: VIII-77-91 Subject: Section VIII, Division 1; Formed Heads Furnished as a Part, UG-11(b) vs UG-77(c) Date Issued: September 30, 1977 File: BC75-239 Question 1: For Section VIII, Division 1 construction there appears to be a possible conflict between the requirements of UG-11(b) and UG-77(c). When a head, wholly formed by forging or die forming, is furnished by a parts manufacturer basically as material under the provisions of UG-11(b) including the required marking and material identification, must the requirements of UG-77(c) concerning marking and material identification also be satisfied? Reply 1: No. Under the stated conditions, the requirements of UG-77(c) do not apply. Question 2: If the answer to Question 1 is negative, under what circumstances is UG-77(c) intended to apply? Reply 2: If, instead of purchasing the heads basically as materials under the provisions of UG-11(b), the vessel manufacturer was contracting work to others under the provisions of U-2(b)(2), the requirements of UG-77(c) would apply. Interpretation: VIII-77-92 Subject: Section VIII, Division 1; UW-52 Date Issued: October 13, 1977 File: BC77-605 Question: The length of weld in a vessel is less than 50 ft.; however, one welding operator is to weld the longitudinal seam and two welding operators are to weld each circumferential seam. Is one spot examination acceptable to satisfy the requirements of UW-52? Reply: Under the provisions of UW-52(b)(2), a spot examination must be made for the welding of each welding operator or welder. The exception to this is a condition under which two or more welders or welding operators make weld layers in a joint in which case one spot examination may represent this work. This rule applies regardless of the fact that the total length of weld in the vessel may be less than 50 ft. Interpretation: VIII-77-93 Subject: Use of SA-487 Class 4Q for Section VIII, Division 1 Construction Date Issued: October 13, 1977 File: BC77-603

Question: May SA-487 Class 4Q be used for construction under Section VIII, Division 1? Reply: No. This material is not presently listed in the appropriate table in Subsection C. ATTENTION The foregoing interpretation has been further considered and the following was added as a clarification and sent to the inquirer. Clarification Issued: May 16, 1978 Question: May SA-487 Class 4Q be used for construction under Section VIII, Division 1, Part UCS? Reply: No; however, this material is presently listed as an approved material in Table UHT-23 in Subsection C and may be used for Section VIII, Division 1 construction in conjunction with the rules of Part UHT. Interpretation: VIII-77-94 Subject: Section VIII, Division 1; Multi-Platen Press Date Issued: October 18, 1977 File: BC77-332 Question 1: The platens of a multi-platen, hydraulic press, such as used in the plywood and laminate industries, are pressured with steam at 150 psig and subsequently cooled with water during each cycle of operation. Do the platens constitute a pressure vessel under the scope of Section VIII, Division 1? Reply 1: The manufacturer and the user of the multi-platen, hydraulic press described above, should carefully review the definitions of U-1(c)(3) regarding rotating or reciprocating mechanical devices in relation to the primary design considerations of your equipment. It appears that your equipment may be excluded from the scope of Section VIII, Division 1. However, we caution you that the laws at the point of installation may dictate the construction. As indicated by footnote 1 to U-1, Scope, such laws must be reviewed to determine requirements that may be different or more restrictive than the Code rules. Question 2: Can you furnish guidance on the design of such multi-platen presses and recommendations on a manufacturing source? Reply 2: No. Such guidance or recommendations is not in the scope of the Committee's activities. Interpretation: VIII-77-95 Subject: Section VIII, Division 1; UG-116 Date Issued: October 20, 1977 File: BC77-564 Question: Is it permissible under the provisions of UG-116 of Section VIII, Division 1 to express the units of pressure and temperature in metric units on the nameplate? Reply: It is intended that the units on the nameplate be expressed in the customary English units, and if metric units are needed, these can be inserted parenthetically next to the appropriate English unit. Interpretation: VIII-77-96

Subject Section VIII, Division 1; Nameplate Stamping Date Issued: October 21, 1977 File: BC74-185 Question: Where a pressure vessel has one independent Code pressure chamber and one independent non-Code pressure chamber, is it permissible to mark the data for the non-Code chamber on the same nameplate that carries the Code symbol and appropriate data for the Code chamber? Reply: No. Under the provisions of UG-119 and UG-116(i), it is intended that only the design data for those portions of the vessel which comply with Section VIII, Division 1 be included in the nameplate having the Code symbol; however, it is recommended that manufacturers attach an additional nameplate (or marking) without the Code symbol indicating the design data for the non-Code chamber. Interpretation: VIII-77-97 Subject: Section VIII, Division 1; UNF-91 Date Issued: November 7, 1977 File: BC77-528 and BC77-702 Question: What is the intent of UNF-91 with regard to the filler metal being of the same composition as the base metal? Reply: In this regard, filler metal would be of a material of alloy which has approximately the same radiation absorption rate as the material being radiographed. The identical alloy, by chemical analysis, is not necessarily required. Interpretation: VIII-77-98 Subject: Section VIII, Division 1; U-1(e) Date Issued: November 7, 1977 File: BC77-527 Question: Is it the intent of U-1(e) that piping and valves subject to pressure, including those with an inside diameter greater than 6 in. but beyond the geometric limits listed in that paragraph, are outside the scope of Section VIII, Division 1? Reply: Yes. Interpretation: VIII-77-99 Subject: Section VIII, Division 1; UG-93 Date Issued: November 9, 1977 File: BC77-593 Question: Are material test reports required for SA-53 Grade A or B for construction under Section VIII, Division 1? Reply: The provisions of UG-93(a)(2) allow for this material to be accepted without obtaining material test reports from the manufacturer provided the pieces are marked in accordance with Section 20 under that specification. Further, the requirements of UG-93 and UG-94 shall be complied with. Interpretation: VIII-77-100 Subject: Section VIII, Division 1; UCS-56, P-No. 4 Materials Date Issued: November 9, 1977

File: BC77-568 Question: Under Table UCS-56, P-No. 4 material, does Note (1)(c)(3) apply as an exemption for castings of SA-217 Grade WC-6, if the percent maximum carbon is restricted to 0.15%? Reply: No. The exemption from postweld heat treatment specified in Note (1)(c)(3) (See Summer 1977 Addenda) applies to pipe or tubes. Postweld heat treatment is mandatory in all cases for this material. Interpretation: VIII-77-101 Subject: Section VIII, Division 1; Inspection Openings, UG-46 Date Issued: November 16,1977 File: BC76-734 Question 1: Do the UG-46 requirements for inspection openings apply to the shell of a fixed tubesheet heat exchanger? Reply 1: The shell of a fixed tubesheet heat exchanger not subject to internal corrosion on the shell side need not be provided with inspection openings. We see no direct conflict in the UG-46(a) requirement for marking the Manufacturer's Data Report "for noncorrosive service" for a vessel containing a standard corrosion allowance such as required by TEMA. Where the shell side fluid has the potential to cause internal corrosion of the shell, the UG-46 requirements apply. Question 2: May telltale holes in accordance with UG-25(e) be used in lieu of the inspection openings required by UG-46 for fixed tubesheet heat exchangers subject to internal corrosion and having a diameter in excess of 36 in.? Reply 2: No. As required by UG-46(b), inspection openings meeting the requirements of UG-46(f)(3) are required for such vessels. Note: The Winter 1977 Addenda will contain a new UG-46(f)(7) "Flanged connection from which piping, instruments, or similar attachments can be removed may be used in place of the required inspection openings provided that: (a) the connections are at least equal to the size of the required openings, and (b) the connections are sized and located to afford at least an equal view of the interior as the required inspection openings." Interpretation: VIII-77-102 Subject: Section VIII, Division 1; UW-15(b) Date Issued: November 28,1977 File: BC77-676 Question 1: Are the values given in UW-15(b) regarding stress values for weld metal to be modified further by the joint efficiencies given in UW-12? Reply 1: No. The values given in UW-15(b) are applicable for calculations pertaining to reinforcement as indicated in UG-41 and as set forth in the examples given in UA-280. Question 2: Is the calculation using the values in UW-15(b) in Section VIII, Division 1 affected by the use of a particular welding process which consequently would result in stress reductions for the values of S in the applicable formulas?

Reply 2: No. Interpretation: VIII-77-103 Subject: Section VIII, Division 1; UG-119(a) Date Issued: November 29, 1977 File: BC77-525 Question: Is it required that the nameplate on a Section VIII, Division 1 pressure vessel be stamped exactly as shown in Fig. UG-118, or may the information concerning the company name and location be placed across the top of the nameplate and code stamp placed in the center? Reply: UG-119(a) of Section VIII, Division 1 states that the arrangements shown in Fig. UG-118 shall be substantially complied with. It is our opinion that the arrangement indicated in the inquiry does not satisfy this requirement. Interpretation: VIII-77-104 Subject: Section VIII, Division 1; UCS-56 Date Issued: November 30, 1977 File: BC77-520 Question: Under the rules of Section VIII, Division 1, may pock-marks, pits, or tears produced on the surface of a carbon or low alloy steel vessel by the improper removal of a thermocouple or other attachment subsequent to postweld heat treatment be repaired by welding without subsequent postweld heat treatment after the completion of the repair if the vessel is in lethal service? Reply: Yes, provided this complies with the Notes to Table UCS-56 for the P-Number material. Interpretation: VIII-77-105 Subject: Section VIII, Division 1; UW-11(a)(5)(b) Date Issued: November 30, 1977 File: BC77-578 Question: Are the provisions of UW-11(a)(5)(b) for partial radiography applicable to individual Category B and C butt welds, regardless of length? Reply: Yes. Interpretation: VIII-77-106 Subject: Section VIII, Division 1; Use of SA-182 Grade F6A Date Issued: December 5,1977 File: BC77-750 Question: In Table UHA-23 SA-182 Grade F6 is listed; however, this material is not included in Section II, Part A nor is it commercially available. May SA-182 Grade F6A be used for Section VIII, Division 1 construction under the provisions of UG-15 using the allowable stresses for SA-479 Grade 410? Reply: Yes.

Interpretation: VIII-77-107 Subject: Section VIII, Division 1; Policy on Certification of Materials Date Issued: December 8, 1977 File: BC77-371 Question: Is it acceptable for a material supplier to transfer information from a Material Manufacturer's Certification or Certificate of Compliance, under his letterhead, in lieu of furnishing a copy of the Material Manufacturer's CMTR or Certificate of Compliance? Reply: It is the intent of the Code that a material supplier shall not transcribe data certified by a Material Manufacturer but shall furnish a copy of that certification, supplemented as necessary by additional documents which certify the results of tests, examinations, repairs, or treatments required by the basic Material Specification and performed by the material supplier. Interpretation: VIII-77-108 Subject: Section VIII, Division 1; UCS-66 Date Issued: December 9, 1977 File: BC77-628 Question: UCS-66(c)(1) indicates that no impact test is required on any material for use at temperatures of -20F and above. Would E-6013 electrodes fall within this category? Reply: Yes. Interpretation: VIII-77-109 Subject: Section VIII, Divisions 1 and 2; Type No. 1 Joints Date Issued: December 20,1977 File: BC77-758 Question: A weld with the following specifications is proposed to be used for Section VIII, Division 1 or Section VIII, Division 2 construction as a Type No. 1 weld used in a Category B location: (a) single side, vee groove weld with no access to back side; (b) root pass made with TIG process with no gas backing or backing strip or back gouging on back side; (c) balance of weld completed with submerged-arc process or manual shielded metal arc process; (d) no consumable insert used, (e) material is carbon steel. Does the above weld qualify as a Type No. 1 weld? Reply: The above weld may qualify as a Type No. 1 weld provided the requirements of UW-35 in Section VIII, Division 1 and AF-220 in Section VIII, Division 2 are met. Verification of the contour of the back side of the weld may necessitate radiographic examination. Interpretation: VIII-77-110 Subject: Section VIII, Division 1; UG-10 Date Issued: December 29, 1977 File: NA

Question: Would it be permissible to have hot rolled carbon-steel bars to AISI No. 1018 tested to ensure that it meets the chemical and mechanical requirements of SA-675, and then use it in place of material to SA-675 for construction of unfired pressure vessels? Reply: A material could be produced to some other specification and be qualified as an SA material provided the Inspector is presented with evidence acceptable to him, including the specific requirements of UG-10, Section VIII, Division 1, indicating that the material satisfies all requirements of the Code approved specification. Interpretation: VIII-78-01 Subject: Section VIII, Division 1, UA-65 Date Issued: January 6, 1978 File: BC77-681 Question: UA-65(b)(1) indicates that "the maximum pore dimension shall be 20% of T, or 1/8 in., whichever is smaller, except that an isolate pore separated from an adjacent pore by 1 in. or more may be 30% of T or 1/4 in., whichever is less". In the foregoing paragraph, do the words after "except" contradict the first part of the paragraph? Reply: No. The words after "except" in the above quoted paragraph override the first portion of the paragraph in the instance where an isolated pore (separated from an adjacent pore by 1 in. or more) exists. Interpretation: VIII-78-02 Subject: Section VIII, Division 1, UW-52(b) Date Issued: January 6, 1978 File: BC77-699 Question: UW-52(b)(2) indicates that "such additional spots as may be required shall be selected so that an examination is made of the welding of each welding operator or welder." Do the words "such additional spots" apply even though the length of linear welding in the vessel is less than 50 ft.? Reply: Yes. The words "such additional spots" apply in the case where more than one welder or welding operator performs on other than 2 or more layers of an individual joint, in which case an examination must be made for each welder or welding operator, regardless of the fact that the length of linear weld may be less than 50 ft. This is an additional requirement to that specified in UW-52(b)(1). Interpretation: VIII-78-03 Subject: Section VIII, Division 1; Code Case 1348, Use of ASTM A 494-62 Date Issued: January 6, 1978 File: BC77-724 Question: Code Case 1348 indicates in Par. (3) of the Reply that no welding is permitted. Is repair by welding of castings conforming to ASTM A 494-62 permissible under the provisions of this Case? Reply: Repair by welding of castings conforming to ASTM A494-62 under the provisions of Case 1348 are only permissible in connection with compliance with the material specification, not in the vessel fabrication.

Interpretation: VIII-78-04 Subject: Section VIII, Division 1, UG-126 Date Issued: January 16, 1978 File: BC77-573 Question: Under footnote 33 to UG-126, 1977 Edition, is it correct to refer to "static pressure" when characterizing the opening or pop action of a safety valve? Reply: Yes. The term "static pressure" is that pressure which tends to exert force on the walls of a pressure vessel and actuates the safety valve as prescribed in UG-134. Interpretation: VIII-78-06 Subject: Section VIII, Division 1, UG-11 and UG-15 Date Issued: January 16, 1978 File: BC77-602 Question: May nozzles be furnished by one fabricator to a manufacturer of a completed vessel out of SB-265 plate which is to be rolled and welded without filler metal? Reply: Such nozzles may be furnished for a Section VIII, Division 1 vessel as described in the question under one of the following options: (1) The nozzle could be furnished as a pressure part, requiring compliance with the applicable material certification rules and Partial Data Report; or (2) The nozzle could be furnished as SB-337 pipe for the same welded grade (note that the chemical and mechanical properties are essentially the same); or (3) The nozzle could be furnished under the provisions of UG-11(c) as a manufacturer's standard in which case all of the rules in UG-11 as applicable to this construction shall be met, including establishing a pressure-temperature rating. Interpretation: VIII-78-07 Subject: Section VIII, Division 1, UW-37(f) Date Issued: January 16, 1978 File: BC77-626 Question: UW-37(f) requires markings for welders and welding operators for vessels in which the wall thickness is less than 1/4 in. for steel material by a stencil or other surface marking unless a record is kept by the manufacturer. May these markings be eradicated after the application of the Code symbol? Reply: Yes, provided the Manufacturer's Data Report has been completed. Interpretation: VIII-78-08 Subject: Section VIII, Division 1; UW-3 Date Issued: January 16, 1978 File: BC77-627 Question: Please verify that the following statements are correct with regard to interpretation of UW-3: (1) UW-3(a) weld Categories define the location of a joint, but not the type of joint.

(2) Category C merely locates the joint. This Category includes all types of flange to nozzle neck connections. (3) The butt welded joint connecting a welding neck flange t