{"operation":"document","citation":"61 FR 8328","title":"Restructuring of Cylinder Specifications Requirements","source_type":"rulemaking","agency":"Research and Special Programs Administration","status":"proposed","official":true,"published_on":"1996-03-04","effective_on":null,"summary":"RSPA is proposing to revise the Hazardous Materials Regulations (HMR) by restructuring the cylinder specification requirements. The intended effect of this rulemaking is to reduce the size of the HMR through consolidation of repetitive requirements and other formatting changes. This action will eliminate pages of regulations without substantially changing the regulatory requirements or affecting safety. It is in response to President Clinton's March 4, 1995 Regulatory Reinvention Initiative memorandum to heads of departments and agencies calling for a review of all agency regulations. RSPA is also proposing to make corresponding reference changes throughout the HMR.","machine_formats":{"json":"https://regulus.evalyn.ai/document/federal-register-96-3554.json","markdown":"https://regulus.evalyn.ai/document/federal-register-96-3554.md"},"app_url":"https://regulus.evalyn.ai/document/federal-register-96-3554","source_url":"https://www.federalregister.gov/documents/1996/03/04/96-3554/restructuring-of-cylinder-specifications-requirements","body":"Federal Register, Volume 61 Issue 43 (Monday, March 4, 1996) [Federal Register Volume 61, Number 43 (Monday, March 4, 1996)] [Proposed Rules] [Pages 8328-8370] From the Federal Register Online via the Government Publishing Office [ www.gpo.gov ] [FR Doc No: 96-3554] [[Page 8327]] _______________________________________________________________________ Part II Department of Transportation _______________________________________________________________________ Research and Special Programs Administration _______________________________________________________________________ 49 CFR Parts 171, 173, and 178 Restructuring of Cylinder Specifications Requirements; Proposed Rule Federal Register / Vol. 61, No. 43 / Monday, March 4, 1996 / Proposed Rules [[Page 8328]] DEPARTMENT OF TRANSPORTATION Research and Special Programs Administration 49 CFR Parts 171, 173, and 178 [Docket HM-220B; Notice No. 96-2] RIN 2137-AC81 Restructuring of Cylinder Specifications Requirements AGENCY: Research and Special Programs Administration (RSPA), DOT. ACTION: Notice of proposed rulemaking (NPRM). ----------------------------------------------------------------------- SUMMARY: RSPA is proposing to revise the Hazardous Materials Regulations (HMR) by restructuring the cylinder specification requirements. The intended effect of this rulemaking is to reduce the size of the HMR through consolidation of repetitive requirements and other formatting changes. This action will eliminate pages of regulations without substantially changing the regulatory requirements or affecting safety. It is in response to President Clinton's March 4, 1995 Regulatory Reinvention Initiative memorandum to heads of departments and agencies calling for a review of all agency regulations. RSPA is also proposing to make corresponding reference changes throughout the HMR. DATES: Comments must be received on or before April 26, 1996. ADDRESSES: Please address written comments to the Dockets Unit (DHM- 30), Research and Special Programs Administration, U.S. Department of Transportation, 400 7th Street, SW., Washington, DC 20590-0001. Comments may also be faxed to (202) 366-3753. Comments should identify the docket (Docket No. HM-220B). The Dockets Unit is located in Room 8421 of the Nassif Building, 400 Seventh Street SW., Washington, DC 20590-0001. Office hours are 8:30 a.m. to 5:00 p.m., Monday through Friday, except on public holidays when the office is closed. FOR FURTHER INFORMATION CONTACT: John A. Gale, (202) 366-8553; Office of Hazardous Materials Standards, RSPA, Department of Transportation, Washington, DC 20590-0001. SUPPLEMENTARY INFORMATION: I. Background On March 4, 1995, President Clinton issued a Regulatory Reinvention Initiative memorandum to heads of departments and agencies calling for a review of all agency regulations and elimination or revision of those regulations that are outdated or in need of reform. RSPA has performed an extensive review of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) and associated procedural rules (49 CFR Parts 106 and 107) in response to the President's directive. The President also directed that front line regulators ``* * * get out of Washington and create grassroots partnerships'' with people affected by agency regulations. On April 4, 1995, RSPA published in the Federal Register (60 FR 17049) a Notice of Public Meetings and request for comment on its hazardous materials safety program. Comments were requested on ways to improve the HMR and the kind and quality of services its customers want. RSPA held seven public meetings and received over 50 comments in response to the notice. On July 28, 1995, RSPA published a second Notice of Public Meetings in the Federal Register (60 FR 38888) which announced five more public meetings that were held from September through January 1996. One area identified by RSPA in its review of the HMR was the need to reform the cylinder specifications in 49 CFR Part 178. RSPA estimates that by consolidating duplicative requirements in 23 cylinder specifications, that it will eliminate at least 40 pages from the CFR. By reformatting the specifications, RSPA proposes to eliminate over 450 sections from Part 178 of Title 49. The combined effect of these changes will be to make the regulations shorter and easier to use and help RSPA move toward a goal of being able to issue the HMR in one volume of the Code of Federal Regulations, rather than two. This rulemaking also serves as the model for a more comprehensive rulemaking, being developed by RSPA in cooperation with the Compressed Gas Association, for which a notice of proposed rulemaking is anticipated later this year. In this latter rulemaking, under Docket HM-220, RSPA intends to propose substantive changes to the cylinder specifications to accommodate contemporary manufacturing techniques, eliminate obsolete requirements, contemporize regulatory language and make safety enhancements to the regulations. II. Proposed Changes In this NPRM, RSPA is proposing to revise the HMR by restructuring the cylinder specification requirements in 49 CFR Part 178. The proposed restructuring of the cylinder specifications would: (1) consolidate similar sections; (2) reformat subpart C of Part 178 for consistency with the format of the rest of Part 178; and (3) revise section references throughout the HMR to correspond to the revised sections. RSPA intends to streamline the cylinder specification requirements without making substantive changes to them. Sections that have been identified by RSPA for consolidation are the sections of each specification addressing compliance, authorized inspectors, duties of the inspector, the inspector's report, record retention, defects, safety relief devices, and marking. These sections will be consolidated into a new Sec. 178.35. Proposed Sec. 178.35, entitled ``General requirements for all DOT specification cylinders'' will prescribe these general requirements for all DOT specification cylinders. However, because some of the duties of the inspector and marking requirements are specific to the individual cylinder design, some specifications would have additional marking and inspector requirements remaining in their sections. For the inspector's report, RSPA has proposed to adopt the inspector report formats in Compressed Gas Association (CGA) Pamphlet C-11, ``Recommended Practices for Inspection of Compressed Gas Cylinders at Time of Manufacture.'' The report formats can be modified to represent the inspection of specific cylinders. Additional information may be required as stated in each specification. Those sections remaining in each specification will be consolidated into a single section. Presently, each specification is set forth in approximately 22 different sections. Under this proposal, there would be only one section for each specification. For example, Specification 3B is currently set forth in 24 sections, Secs. 178.38 through 178.38- 23. In this NPRM, Specification 3B is set forth in one section, Sec. 178.38. Some of the requirements are relocated in Sec. 178.35. Sixteen of the old sections are converted to paragraphs (a) through (o) of Sec. 178.38. As an aid to the reader, the regulatory text in this notice includes all of the requirements for cylinders in the current Subpart C of part 178, even though not all of the requirements are changed. The purpose of this rulemaking action is to reduce the size of the HMR and make it easier to use. It is not intended to make substantive changes to regulatory requirements and no adverse impacts are anticipated on the regulated community. [[Page 8329]] III. Regulatory Analyses and Notices Executive Order 12866 and DOT Regulatory Policies and Procedures This proposed rule is not considered a significant regulatory action under section 3(f) of Executive Order 12866 and was not reviewed by the Office of Management and Budget. The rule is not considered significant under the regulatory policies and procedures of the Department of Transportation (44 FR 11034). The economic impact of this rule is minimal to the extent that the preparation of a regulatory evaluation is not warranted. Executive Order 12612 This proposed rule has been analyzed in accordance with the principles and criteria contained in Executive Order 12612 (``Federalism''). The Federal hazardous materials transportation law (49 U.S.C. 5101-5127) contains an express preemption provision that preempts State, local, and Indian tribe requirements on certain covered subjects. Covered subjects are: (i) the designation, description, and classification of hazardous material; (ii) the packing, repacking, handling, labeling, marking, and placarding of hazardous material; (iii) the preparation, execution, and use of shipping documents pertaining to hazardous material and requirements respecting the number, content, and placement of such documents; (iv) the written notification, recording, and reporting of the unintentional release in transportation of hazardous material; or (v) the design, manufacturing, fabrication, marking, maintenance, reconditioning, repairing, or testing of a package or container which is represented, marked, certified, or sold as qualified for use in the transportation of hazardous material. The Federal hazardous materials transportation law provides that if DOT issues a regulation concerning any of the covered subjects after November 16, 1990, DOT must determine and publish in the Federal Register the effective date of Federal preemption. 49 U.S.C. 5125(b)(2). That effective date may not be earlier than the 90th day following the date of issuance of the final rule and not later than two years after the date of issuance. This proposed rule deals with the packaging of compressed gases. Although this proposal does not contemplate substantive changes, RSPA solicits comments on whether the proposed rule would have any effect on State, local or Indian tribe requirements and, if so, the most appropriate effective date of Federal preemption. Because RSPA lacks discretion in this area, preparation of a federalism assessment is not warranted. Regulatory Flexibility Act I certify that this proposed rule will not have a significant economic impact on a substantial number of small entities. This proposed rule does not impose any new requirements on persons subject to the HMR. Paperwork Reduction Act This proposed rule does not propose any new information collection requirements. Regulation Identifier Number (RIN) A regulation identifier number (RIN) is assigned to each regulatory action listed in the Unified Agenda of Federal Regulations. The Regulatory Information Service Center publishes the Unified Agenda in April and October of each year. The RIN number contained in the heading of this document can be used to cross-reference this action with the Unified Agenda. List of Subjects 49 CFR Part 171 Exports, Hazardous materials transportation, Hazardous waste, Imports, Reporting and recordkeeping requirements. 49 CFR Part 173 Hazardous materials transportation, Packaging and containers, Radioactive materials, Reporting and recordkeeping requirements, Uranium. 49 CFR Part 178 Hazardous materials transportation, Packaging and containers, Reporting and recordkeeping requirements. In consideration of the foregoing, 49 CFR parts 171, 173, and 178 would be amended to read as follows: PART 171--GENERAL INFORMATION, REGULATIONS, AND DEFINITIONS 1. The authority citation for Part 171 would continue to read as follows: Authority: 49 U.S.C. 5101-5127; 49 CFR part 1.53. 2. In Sec. 171.7(a)(3), in the table, under the entry ``Aluminum Standards and Data, Seventh Edition, June 1982'', the section reference ``178.65-5'' is revised to read ``178.65''; and under the entry Compressed Gas Association, Inc., a new entry is added in alpha- numerical order to read as follows: Sec. 171.7 Reference material. * * * * * (a) * * * (3) * * * ------------------------------------------------------------------------ 49 CFR Source and name of material reference ------------------------------------------------------------------------ * * * * * Compressed Gas Association, Inc., * * * * * CGA Pamphlet C-11, Recommended Practices for Inspection of Compressed Gas Cylinders at Time of Manufacture, 1993...... 178.35 * * * * * ------------------------------------------------------------------------ * * * * * PART 173--SHIPPERS--GENERAL REQUIREMENTS FOR SHIPMENTS AND PACKAGINGS 3. The authority citation for Part 173 would continue to read as follows: Authority: 49 U.S.C. 5101-5127; 49 CFR part 1.53. Sec. 173.34 [Amended] 4. In Sec. 173.34, paragraph (h) would be amended by: a. Removing, in the first sentence, the phrase ``Secs. 178.36-9(a), 178.37-9(a), 178.38-9(a), and 178.40-9(a)'' and replacing it with the phrase ``Secs. 178.36(e), 178.37(e), 178.38(e), and 178.40(e)''. b. Removing, in the fourth sentence, the phrase ``Sec. 178.36-9(a), Sec. 178.37-9(a), Sec. 178.38-9(a), or Sec. 178.40-9(a)'' and replacing it with the phrase ``Sec. 178.36(e), Sec. 178.37(e), Sec. 178.38(e), or Sec. 178.40(e)''. Sec. 173.316 [Amended] 5. In Sec. 173.316, in paragraph (a)(8), the section reference ``178.57- 20(a)(4)'' would be revised to read ``178.35'' and in paragraph (c)(3)(ii) the section reference ``178.57-20'' would be revised to read ``178.35''. PART 178--SPECIFICATIONS FOR PACKAGINGS 6. The authority citation for Part 178 would continue to read as follows: Authority: 49 U.S.C. 5101-5127; 49 CFR 1.53. 7. Subpart C of Part 178 would be revised to read as follows: Subpart C--Specifications for Cylinders Sec. 178.35 General requirements for specification cylinders. 178.36 Specifications 3A and 3AX seamless steel cylinders. 178.37 Specification 3AA and 3AAX seamless steel cylinders. [[Page 8330]] 178.38 Specification 3B seamless steel cylinders. 178.39 Specification 3BN seamless nickel cylinders. 178.42 Specification 3E seamless steel cylinders. 178.44 Specification 3HT seamless steel cylinders for aircraft use. 178.45 Specification 3T seamless steel cylinder. 178.46 Specification 3AL seamless aluminum cylinders. 178.47 Specification 4DS welded stainless steel cylinders for aircraft use. 178.50 Specification 4B welded or brazed steel cylinders. 178.51 Specification 4BA welded or brazed steel cylinders. 178.53 Specification 4D welded steel cylinders for aircraft use. 178.55 Specification 4B240ET welded or brazed cylinders. 178.56 Specification 4AA480 welded steel cylinders. 178.57 Specification 4L welded insulated cylinders. 178.58 Specification 4DA welded steel cylinders for aircraft use. 178.59 Specification 8 steel cylinders with porous fillings for acetylene. 178.60 Specification 8AL steel cylinders with porous fillings for acetylene. 178.61 Specification 4BW welded steel cylinders with electric-arc welded longitudinal seam. 178.65 Specification 39 non-reusable (non-refillable) cylinders. 178.68 Specification 4E welded aluminum cylinders. Subpart C--Specifications for Cylinders Sec. 178.35 General requirements for specification cylinders. (a) Compliance with the requirements of this subpart is required in all details. (b) Inspections and analyses. Chemical analyses and tests as specified must be made within the United States unless otherwise approved in writing by the Associate Administrator, in accordance with Sec. 173.300b of this subchapter. Inspections and verifications must be performed by-- (1) An independent inspection agency approved in writing by the Associate Administrator, in accordance with Sec. 173.300a of this subchapter; or (2) For DOT Specifications 3B, 3BN, 4B, 4BA, 4D (water capacity less than 1,100 cubic inches), 4B240ET, 4AA480, 4L, 8, 8AL, 4BW, 39 (marked service pressure 900 p.s.i.g. or lower) and 4E manufactured in the United States, a competent inspector of the manufacturer. (c) Duties of inspector. The inspector shall determine that each cylinder made is in conformance with the applicable specification. Except as otherwise specified in the applicable specification, the inspector shall perform the following: (1) Inspect all material and reject any not meeting applicable requirements. For cylinders made by the billet-piercing process, billets must be inspected and shown to be free from pipe, cracks, excessive segregation and other injurious defects after parting or, when applicable, after nick and cold break. (2) Verify the material of construction meets the requirements of the applicable specification by-- (i) Making a chemical analysis of each heat of material; (ii) Obtaining a certified chemical analysis from the material manufacturer for each heat of material (a ladle analysis is acceptable); or (iii) If an analysis is not provided for each heat of material by the material manufacturer, by making a check analysis of a sample from each coil, sheet, or tube. (3) Verify compliance of cylinders with the applicable specification by-- (i) Verifying identification of material is proper; (ii) Inspecting the inside of the cylinder before closing in ends; (iii) Verifying that the heat treatment is proper; (iv) Obtaining samples for all tests and check chemical analyses; (v) Witnessing all tests; (vi) Verify threads by gauge; (vii) Reporting volumetric capacity and tare weight (see report form) and minimum thickness of wall noted; and (viii) Verifying that each cylinder is marked in accordance with the applicable specification. (4) Furnish complete test reports required by this subpart to the maker of the cylinder and, upon request, to the purchaser. The test report must be retained by the inspector for fifteen years from the original test date of the cylinder. (d) Defects. A cylinder may not be constructed of material with seams, cracks, laminations, or other injurious defects. (e) Safety devices and protection for valves, safety devices, and other connections, if applied, must be as required or authorized by the appropriate specification, and as required in Secs. 173.34 and 173.301 of this subchapter. (f) Markings. Markings on a DOT Specification cylinder must conform to applicable requirements. (1) Each cylinder must be marked with the following information: (i) The DOT specification marking must appear first, followed immediately by the service pressure. For example, DOT-3A1800. (ii) The serial number must be placed just below or immediately following the DOT specification marking. (iii) A symbol (letters) must be placed just below, immediately before or following the serial number. Other variations in sequence of markings are authorized only when necessitated by a lack of space. The symbol and numbers must be those of the manufacturer. The symbol must be registered with the Associate Administrator; duplications are not authorized. (iv) The inspector's official mark and date of test (such as 5-95 for May 1995) must be placed near the serial number. This information must be placed so that dates of subsequent tests can be easily added. An example of the markings prescribed in this paragraph (f)(1) is as follows: DOT-3A1800 1234 XY AB 5-95 or; DOT-3A1800-1234-XY AB 5-95 where: DOT-3A = specification number 1800 = service pressure 1234 = serial number xy = symbol of manufacturer AB = inspector's mark 5-95 = date of test (2) Additional required marking must be applied to the cylinder as follows: (i) The word ``spun'' or ``plug'' must be placed near the DOT specification marking when an end closure in the finished cylinder has been welded by the spinning process, or effected by plugging. (ii) As prescribed in specification 3HT (Sec. 178.44) or 3T (Sec. 178.45), if applicable. (3) Marking exceptions. (i) A DOT 3E cylinder is not required to be marked with the inspector mark. (ii) An identifying lot number may be marked on the cylinder in place of a serial number for cylinders not over 2 inches outside diameter or for cylinders with a volumetric capacity not exceeding 60 cubic inches. Each lot shall not have over 500 cylinders. (4) Unless otherwise specified in the applicable specification, the markings on each cylinder must be stamped plainly and permanently on the shoulder, top head, or neck. (5) The size of each marking must be least 0.25 inch or as space permits. (6) Other markings are authorized provided they are made in low stress areas other than the side wall and are not of a size and depth that will create harmful stress concentrations. Such [[Page 8331]] marks may not conflict with any DOT required markings. (g) Inspector's report. Each inspector shall prepare a report containing, at a minimum, the applicable information listed in CGA Pamphlet C-11. Any additional information or markings that are required by the applicable specification must be shown on the test report. The signature of the inspector on the reports certifies that the processes of manufacture and heat treatment of cylinders were observed and found satisfactory. (h) Report Retention. The manufacturer of the cylinders shall retain the reports required by this subpart for 15 years from the original test date of the cylinder. Sec. 178.36 Specification 3A and 3AX seamless steel cylinders. (a) Type size and service pressure. In addition to the requirements of Sec. 178.35, cylinders must conform to the following: (1) A DOT-3A cylinder is a seamless steel cylinder with a water capacity (nominal) not over 1,000 pounds and a service pressure of at least 150 pounds per square inch. (2) A DOT-3AX is a seamless stainless steel cylinder with a water capacity not less than 1,000 pounds and a service pressure of at least 500 pounds per square inch, conforming to the following requirements: (i) Assuming the cylinder is to be supported horizontally at its two ends only and to be uniformly loaded over its entire length consisting of the weight per unit of length of the straight cylindrical portion filled with water and compressed to the specified test pressure; the sum of two times the maximum tensile stress in the bottom fibers due to bending, plus that in the same fibers (longitudinal stress), due to hydrostatic test may not exceed 80 percent of the minimum yield strength of the steel at such maximum stress. Wall thickness must be increased when necessary to meet the requirement. (ii) To calculate the maximum longitudinal tensile stress due to bending, the following formula must be used: S=Mc/I (iii) To calculate the maximum longitudinal tensile stress due to hydrostatic test pressure, the following formula must be used: S=A 1P/A 2 where: S = tensile stress-p.s.i.; M = bending moment-inch pounds (wl\\2\\)/8; w = weight per inch of cylinder filled with water; l = length of cylinder-inches; c = radius (D)/(2) of cylinder-inches; I = moment of inertia-0.04909 (D\\4\\-d\\4\\) inches fourth; D = outside diameter-inches; d = inside diameter-inches; A 1 = internal area in cross section of cylinder-square inches; A 2 = area of metal in cross section of cylinder-square inches; P = hydrostatic test pressure-p.s.i. (b) Steel. Open-hearth or electric steel of uniform quality must be used. Content percent may not exceed the following: Carbon, 0.55; phosphorous, 0.045; sulphur, 0.050. (c) Identification of material. Material must be identified by any suitable method, except that plates and billets for hot-drawn cylinders must be marked with the heat number. (d) Manufacture. Cylinders must be manufactured using equipment and processes adequate to ensure that each cylinder produced conforms to the requirements of this subpart. No fissure or other defect is permitted that is likely to weaken the finished cylinder appreciably. A reasonably smooth and uniform surface finish is required. If not originally free from such defects, the surface may be machined or otherwise treated to eliminate these defects. The thickness of the bottoms of cylinders welded or formed by spinning is, under no condition, to be less than two times the minimum wall thickness of the cylindrical shell; such bottom thicknesses must be measured within an area bounded by a line representing the points of contact between the cylinder and floor when the cylinder is in a vertical position. (e) Welding or brazing. Welding or brazing for any purpose whatsoever is prohibited except as follows: (1) Welding or brazing is authorized for the attachment of neckrings and footrings which are non-pressure parts and only to the tops and bottoms of cylinders having a service pressure of 500 pounds per square inch or less. Cylinders, neckrings, and footrings must be made of weldable steel, the carbon content of which may not exceed 0.25 percent except in the case of 4130X steel which may be used with proper welding procedures. (2) As permitted in paragraph (d) of this section. (3) Cylinders used solely in anhydrous ammonia service may have a \\1/2\\ inch diameter bar welded within their concave bottoms. (f) Wall thickness. For cylinders with service pressure less than 900 pounds, the wall stress may not exceed 24,000 pounds per square inch. A minimum wall thickness of 0.100 inch is required for any cylinder over 5 inches outside diameter. Wall stress calculation must be made by using the following formula: S=[P(1.3D\\2\\+0.4d\\2\\)]/(D\\2\\-d\\2\\) where: S=wall stress in pounds per square inch; P=minimum test pressure prescribed for water jacket test or 450 pounds per square inch whichever is the greater; D=outside diameter in inches; d=inside diameter in inches. (g) Heat treatment. The completed cylinder must be uniformly and properly heat-treated prior to tests. (h) Openings in cylinders and connections (valves, fuse plugs, etc.) for those openings. Threads are required on openings. (1) Threads must be clean cut, even, without checks, and to gauge. (2) Taper threads, when used, must be of length not less than as specified for American Standard taper pipe threads. (3) Straight threads having at least 6 engaged threads are authorized. Straight threads must have a tight fit and calculated shear strength of at least 10 times the test pressure of the cylinder. Gaskets, adequate to prevent leakage, are required. (i) Hydrostatic test. Each cylinder must successfully withstand a hydrostatic test, as follows: (1) The test must be by water-jacket, or other suitable methods, operated so as to obtain accurate data. The pressure gauge must permit reading to an accuracy of 1 percent. The expansion gauge must permit reading of total expansion to an accuracy of either 1 percent or 0.1 cubic centimeter. (2) Pressure must be maintained for at least 30 seconds and sufficiently longer to ensure complete expansion. Any internal pressure applied after heat-treatment and previous to the official test may not exceed 90 percent of the test pressure. If, due to failure of the test apparatus the test pressure cannot be maintained the test may be repeated at a pressure increased by 10 percent or 100 pounds per square inch, whichever is the lower. (3) Permanent, volumetric expansion may not exceed 10 percent of the total volumetric expansion at test pressure. (4) Each cylinder must be tested to at least 5/3 times service pressure. (j) Flattening test. A flattening test must be performed on one cylinder taken at random out or each lot of 200 or less, by placing the cylinder between wedge shaped knife edges having a 60 deg. included angle, rounded to \\1/2\\-inch radius. The longitudinal axis of the cylinder must be at a 90-degree angle to [[Page 8332]] knife edges during the test. For lots of 30 or less, flattening tests are authorized to be made on a ring at least 8 inches long cut from each cylinder and subjected to same heat treatment as the finished cylinder. (k) Physical test. A physical test must be conducted to determine yield strength, tensile strength, elongation, and reduction of area of material as follows: (1) The test is required on 2 specimens cut from 1 cylinder taken at random out of each lot of 200 or less. For lots of 30 or less, physical tests are authorized to be made on a ring at least 8 inches long cut from each cylinder and subjected to same heat treatment as the finished cylinder. (2) Specimens must conform to the following: (i) Gauge length of 8 inches with a width of not over 1\\1/2\\ inches, a gauge length of 2 inches with a width of not over 1\\1/2\\ inches, or a gauge length of at least 24 times thickness with width not over 6 times thickness is authorized when cylinder wall is not over \\3/ 16\\ inch thick. (ii) The specimen, exclusive of grip ends, may not be flattened. Grip ends may be flattened to within 1 inch of each end of the reduced section. (iii) When size of cylinder does not permit securing straight specimens, the specimens may be taken in any location or direction and may be straightened or flattened cold, by pressure only, not by blows. When specimens are so taken and prepared, the inspector's report must show in connection with record of physical tests detailed information in regard to such specimens. (iv) Heating of a specimen for any purpose is not authorized. (3) The yield strength in tension must be the stress corresponding to a permanent strain of 0.2 percent of the gauge length. The following conditions apply: (i) The yield strength must be determined by either the ``offset'' method or the ``extension under load'' method as prescribed in ASTM Standard E8-78. (ii) In using the ``extension under load'' method, the total strain (or ``extension under load'') corresponding to the stress at which the 0.2-percent permanent strain occurs may be determined with sufficient accuracy by calculating the elastic extension of the gauge length under appropriate load and adding thereto 0.2 percent of the gauge length. Elastic extension calculations must be based on an elastic modulus of 30,000,000. In the event of controversy the entire stress-strain diagram must be plotted and the yield strength determined from the 0.2 percent offset. (iii) For the purpose of strain measurement, the initial strain must be set while the specimen is under a stress of 12,000 pounds per square inch and the strain indicator reading must be set at the calculated corresponding strain. (iv) Cross-head speed of the testing machine may not exceed \\1/8\\ inch per minute during yield strength determination. (l) Acceptable results for physical and flattening tests. Either of the following is an acceptable result: (1) An elongation at least 40 percent for a 2-inch gauge length or at least 20 percent in other cases and yield strength not over 73 percent of tensile strength. In this instance, the flattening test is not required. (2) An elongation at least 20 percent for a 2-inch gauge length or 10 percent in other cases and a yield strength not over 73 percent of tensile strength. In this instance, the flattening test is required, without cracking, to 6 times the wall thickness. (m) Leakage test. All spun cylinders and plugged cylinders must be tested for leakage by gas or air pressure after the bottom has been cleaned and is free from all moisture subject to the following conditions and limitations: (1) Pressure, approximately the same as but no less than service pressure, must be applied to one side of the finished bottom over an area of at least \\1/16\\ of the total area of the bottom but not less than \\3/4\\ inch in diameter, including the closure, for at least 1 minute, during which time the other side of the bottom exposed to pressure must be covered with water and closely examined for indications of leakage. Except as provided in paragraph (n) of this section, a cylinder that is leaking must be rejected. (2) A spun cylinder is one in which an end closure in the finished cylinder has been welded by the spinning process. (3) A plugged cylinder is one in which a permanent closure in the bottom of a finished cylinder has been effected by a plug. (4) As a safety precaution, if the manufacturer elects to make this test before the hydrostatic test, the manufacturer should design the test apparatus so that the pressure is applied to the smallest area practicable, around the point of closure, and so as to use the smallest possible volume of air or gas. (n) Rejected cylinders. Reheat treatment is authorized for rejected cylinders. Subsequent thereto, cylinders must pass all prescribed tests to be acceptable. Repair by welding or spinning is not authorized. Spun cylinders rejected under the provisions of paragraph (m) of this section may be removed from the spun cylinder category by drilling to remove defective material, tapping and plugging. Sec. 178.37 Specification 3AA and 3AAX seamless steel cylinders. (a) Type, size and service pressure. In addition to the requirements of Sec. 178.35, cylinders must conform to the following: (1) A DOT-3AA cylinder is a seamless steel cylinder with a water capacity (nominal) of not over 1,000 pounds and a service pressure of at least 150 pounds per square inch. (2) A DOT-3AAX cylinder is a seamless steel cylinder with a water capacity of not less than 1,000 pounds and a service pressure of at least 500 pounds per square inch, conforming to the following requirements: (i) Assuming the cylinder is to be supported horizontally at its two ends only and to be uniformly loaded over its entire length consisting of the weight per unit of length of the straight cylindrical portion filled with water and compressed to the specified test pressure; the sum of two times the maximum tensile stress in the bottom fibers due to bending, plus that in the same fibers (longitudinal stress), due to hydrostatic test pressure may not exceed 80 percent of the minimum yield strength of the steel at such maximum stress. Wall thickness must be increased when necessary to meet the requirement. (ii) To calculate the maximum tensile stress due to bending, the following formula must be used: S=Mc/I (iii) To calculate the maximum longitudinal tensile stress due to hydrostatic test pressure, the following formula must be used: S=A\\1\\P/A\\2\\ where: S=tensile stress-p.s.i.; M=bending moment-inch pounds (wl\\2\\)/8; w=weight per inch of cylinder filled with water; l=length of cylinder-inches; c=radius (D)/(2) of cylinder-inches; I=moment of inertia-0.04909 (D\\4\\-d\\4\\) inches fourth; D=outside diameter-inches; d=inside diameter-inches; A\\1\\=internal area in cross section of cylinder-square inches; A\\2\\=area of metal in cross section of cylinder-square inches; P=hydrostatic test pressure-p.s.i. (b) Authorized steel. Open-hearth, basic oxygen, or electric steel of uniform [[Page 8333]] quality must be used. A heat of steel made under the specifications in Table 1 of this paragraph (b), check chemical analysis of which is slightly out of the specified range, is acceptable, if satisfactory in all other respects, provided the tolerance shown in Table 2 of this paragraph (b) are not exceeded. When a carbon-boron steel is used, a hardenability test must be performed on the first and last ingot of each heat of steel. The results of this test must be recorded on the Record of Chemical Analysis of Material for Cylinders required by Sec. 178.35. This hardness test must be made \\5/16\\-inch from the quenched end of the Jominy quench bar and the hardness must be at least Rc 33 and no more than Rc 53. The following chemical analyses are authorized: Table 1.--Authorized Materials -------------------------------------------------------------------------------------------------------------------------------------------------------- Intermediate Designation 4130X (percent) NE-8630 (percent) 9115 (percent) (see 9125 (percent) Carbon-boron manganese (see Note 1) (see Note 1) Note 1) (see Note 1) (percent) (percent) -------------------------------------------------------------------------------------------------------------------------------------------------------- Carbon....................... 0.25/0.35.......... 0.28/0.33.......... 0.10/0.20.......... 0.20/0.30......... 0.27-0.37......... 0.40 max. Manganese.................... 0.40/0.90.......... 0.70/0.90.......... 0.50/0.75.......... 0.50/0.75......... 0.80-1.40......... 1.35/1.65 Phosphorus................... 0.04 max........... 0.04 max........... 0.04 max........... 0.04 max.......... 0.035 max......... 0.04 max. Sulfur....................... 0.05 max........... 0.04 max........... 0.04 max........... 0.04 max.......... 0.045 max......... 0.05 max. Silicon...................... 0.15/0.35.......... 0.20/0.35.......... 0.60/0.90.......... 0.60/0.90......... 0.3 max........... 0.10/0.30 Chromium..................... 0.80/1.10.......... 0.40/0.60.......... 0.50/0.65.......... 0.50/0.65......... .................. .................. Molybdenum................... 0.15/0.25.......... 0.15/0.25.......... ................... .................. .................. .................. Zirconium.................... ................... ................... 0.05/0.15.......... 0.05/0.15......... .................. .................. Nickel....................... ................... 0.40/0.70.......... ................... .................. .................. .................. Boron........................ ................... ................... ................... .................. 0.0005/0.003 .................. -------------------------------------------------------------------------------------------------------------------------------------------------------- Note 1: This designation may not be restrictive and the commercial steel is limited in analysis as shown in this Table 1. Table 2.--Check Analysis Tolerances ---------------------------------------------------------------------------------------------------------------- Tolerance (percent) over the maximum limit or under the Limit or maximum specified minimum limit Element (percent) ------------------------------- Under minimum Over maximum limit limit ---------------------------------------------------------------------------------------------------------------- Carbon........................................ To 0.15 incl.................... 0.02 0.03 Over 0.15 to 0.40 incl.......... .03 .04 Manganese..................................... To 0.60 incl.................... .03 .03 Over 0.60 to 1.15 incl.......... .04 .04 Over 1.15 to 2.50 incl.......... .05 .05 Phosphorus \\1\\................................ All ranges...................... .............. .01 Sulphur....................................... All ranges...................... .............. .01 Silicon....................................... To 0.30 incl.................... .02 .03 Over 0.30 to 1.00 incl.......... .05 .05 Nickel........................................ To 1.00 incl.................... .03 .03 Chromium...................................... To 0.90 incl.................... .03 .03 0.90 to 2.90 incl............... .05 .05 Molybdenum.................................... To 0.20 incl.................... .01 .01 Over 0.20 to 0.40............... .02 .02 Zirconium..................................... All ranges...................... .01 .05 ---------------------------------------------------------------------------------------------------------------- \\1\\ Rephosphorized steels not subject to check analysis for phosphorus. (c) Identification of material. Material must be identified by any suitable method except that plates and billets for hot-drawn cylinders must be marked with the heat number. (d) Manufacture. Cylinders must be manufactured using equipment and processes adequate to ensure that each cylinder produced conforms to the requirements of this subpart. No fissure or other defects is permitted that is likely to weaken the finished cylinder appreciably. A reasonably smooth and uniform surface finish is required. If not originally free from such defects, the surface may be machined or otherwise treated to eliminate these defects. The thickness of the bottoms of cylinders welded or formed by spinning is, under no condition, to be less than two times the minimum wall thickness of the cylindrical shell; such bottom thicknesses must be measured within an area bounded by ","truncated":true,"body_characters":289635}