{"operation":"document","citation":"98-0551","title":"Worthington Cylinder Corporation — Hazardous Materials Safety Interpretation","source_type":"guidance","agency":"Pipeline and Hazardous Materials Safety Administration","status":"guidance","official":true,"published_on":"1998-04-15","effective_on":null,"summary":"98-0551 response to Worthington Cylinder Corporation concerning 178.68.","machine_formats":{"json":"https://regulus.evalyn.ai/document/phmsa-interpretation-98-0551.json","markdown":"https://regulus.evalyn.ai/document/phmsa-interpretation-98-0551.md"},"app_url":"https://regulus.evalyn.ai/document/phmsa-interpretation-98-0551","source_url":"https://www.phmsa.dot.gov/sites/phmsa.dot.gov/files/legacy/interpretations/Interpretation%20Files/1998/980551.pdf","body":"<<<PAGE 1>>>\n\n1\n•\nU.S. Department\nof Transportation\nWashington, D.C. 20590\n400 Seventh Street, S.W.\nSpecial Programs\nResearch and\nAdministration\nAPR 1 5 1998\nMr. Steven I. Gentry\nWorthington Cylinder Corporation\nP.O. Box 391\n1085 Dearborn Drive\nColumbus, Ohio 43085\n•\nDear Mr. Gentry:\n•\nThis is in response to your inquiry requesting clarification of the testing requirements for DOT 4E\nspecification cylinders. Your questions are paraphrased below, followed by our answers.\nQ1:\nAre weld tensile specimens tested per 49 CFR § 178.68-17(a) (now § 178.68(I)(1))\nrequired to meet both apparent and actual breaking stress requirements?\nAl:\nYes. The specimen must meet both requirements to pass the test.\nQ2:\nWhat are the minimum wall thickness requirements of 49 CFR 178.68-10 (now\n§ 178.68(f)?\nA2:\nThe absolute minimum wall thickness is 0.140. In addition, the minimum wall thickness\nmust be such that the calculated wall stress at twice the service pressure is less than\n20,000 psi or 1/2 the minimum tensile strength, whichever is less. The minimum tensile\nstrength is determined in accordance with § 178.68(i).\nQ3:\nWhere should the thickness of tensile coupons be measured?\n.A3:\nAccording to ASTM E8, paragraph 7.1.1: \"For referee testing of specimens under 3/16 in.\nin their least dimension, measure the dimensions where the least cross-sectional area is\nfound\".\nI hope this information is helpful. If we can be of further assistance, please contact us.\nSincerely,\nFor Hattie L. Mitchell\nChief, Regulatory Review and Reinvention\nOffice of Hazardous Materials Standards\n•\n\n<<<PAGE 2>>>\n\nOFFICE OF CHEE COUNSEL\nWorthington Cylinder\n97 APR 8 AMII: 12)\nCorporation\nApril 2, 1997\nOffice of Chief Council\nRSPA\nU.S. Department of Transportation\n400 Seventh Street S.W.\nWashington, D.C. 20590\nDear Sir or Madam:\nWorthington Cylinder Corporation sent you a request for an interpretation of the 4E\nSpecification October 24, 1996. This letter was sent to you via Registered Mail and was received\nat your location on November 1, 1997 (see attached copy of Registered Mail card). I have\nenclosed another copy of our request for your review.\n'As to date, we have had no response from the DOT on our request. I have tried on numerous\noccasions to contact a representative from DOT on this issue but, have received no telephone call\nback. This is an important issue to Worthington Cylinder Corporation and would appreciate a\nresponse to our inquiry as soon as possible.\nThank you for your cooperation in this matter.\nSincerely:\nни Sai\nProject Engineer\nWorthington Cylinder Corporation\nattachments\n•\nP.O. Box 391, 1085 Dearborn Dr. • Columbus, Ohio 43085 • Tel. (614) 438-3013 • FAX (614) 438-3083\nA SUBSIDIARY OF WORTHINGTON INDUSTRIES, INC.\n\n<<<PAGE 3>>>\n\nWorthington Cylinder\nCorporation\nOctober 24, 1996\nOffice of Chief Council\nU.S. Department of Transportation\n400 Seventh Street S.W.\nWashington, D.C. 20590\nDear Sir or Madam:\nWorthington Cylinder Corporation has some questions concerning 49 CFR 178.68 titled Specification\n4E. We are asking the U.S. Department of Transportation for their official interpretation on these issues.\nQUESTION #1\nParagraph 178.68-17(a) states that the weld tensile specimen must have an actual breaking stress of at\nleast 30,000 psi and a minimum apparent breaking of stress of 2 times the minimum cylinder sidewall\ntensile strength as defined in the formula in Paragraph 178.68-10(b).\nFor an example, I will use 3 cylinders manufactured to Specification 4E. Each cylinder has a test\nindicates a minimum wall stress of 17,662 psi and a minimum tensile strength requirement of 35,324 psi.\npressure of 480 psi, inside diameter of 12 inches and a minimum sidewall thickness of .142 inches. This\nWe test the welds and determine the following information :\nACTUAL WELD TENSILE STRENGTH\nCYLINDER\nACTUAL\nACTUAL\nSAMPLE\nNUMBER\nTHICKNESS\nSAMPLE\nSAMPLE\nWIDTH\nAREA\nIN?\nLOAD\nTENSILE\n1\n0.160\nPOUNDS\nSTRENGTH\nPSI\nPASS / FAIL\n≥30,000\n0.500\n0.0800\n2\n0.155\n0.500\n0.0775\n2520\n31,500\nPASS\n3\n2200\n0.158\n0.500\n0.0790\n28,387\nFAIL\n2400\n30,380\nPASS\nAPPARENT WELD TENSILE, STRENGTH\nAPPARENT\nCYLINDER\nNUMBER\nTHICKNESS\nSAMPLE\nACTUAL\nSAMPLE\nSAMPLE\nTENSILE\nWIDTH\nAREA\nIN?\nLOAD\nPOUNDS\nSTRENGTH\n≥ 35,324\n1\n0.142\n0.500\n0.0710\nPSI\nPASS / FAIL\n2520\n2\n0.142\n0.500\n0.0710\n35,493\nPASS\n3\n0.142\n2200\n0.500\n0.0710\n30,986\nFAIL\n2400\n33,803\nFAIL\n.O. Box 391, 1085 Dearborn Dr. • Columbus, Ohio 43085 • Tel. (614) 438-3013 • Fax (614) 438-308\n, SUBSIDIARY OF WORTHINGTON INDUSTRIES, INC\n\n<<<PAGE 4>>>\n\n•\nIt is our interpretation that the only cylinder that passed the requirements of Paragraph\n178.68-17(a) is Cylinder #1. This cylinder met both requirements of the 30,000 psi\nminimum actual weld tensile strength and 35,324 psi apparent weld tensile strength.\nCylinder #2 failed because the actual and apparent weld tensile strengths were below the\n30,000 psi and 35,240 psi requirements. Cylinder #3 failed because the apparent weld\ntensile strength was below the 35,240 psi requirement.\nWe are asking that you confirm our interpretation.\nQUESTION #2\nParagraph 178.68-10 discusses the minimum wall thickness that is required for a Specification 4E\ncylinder. Part (a) of this paragraph states that in any case, the cylinder wall thickness shall never be less\nthan 0.140 inches. Additionally, the stress calculation shall not exceed 20,000 psi and the wall thickness\nused in the stress calculation shall be the determining factor for the minimum sidewall tensile strength.\nPart (c) goes further to state, that the minimum thickness of the heads and bottoms shall not be less than\nthe minimum required sidewall thickness.\nI have enclosed Attachment A for your review. This drawing illustrates 3 cylinders manufactured to\nSpecification 4E. The purpose of this drawing is to illustrate the defined minimum wall thickness of the\ncylinder in accordance with Paragraph 178.68-10. We will assume that the wall stress calculation has\nindicated the minimum sidewall thickness as 0.142 inches. We will assume that the cylinder sidewall\nhas the tensile strength required of the stress calculation times a factor of two (in this case 35,324 psi).\n•\nIt is our interpretation of Paragraph 178.68-10 that all 3 cylinders comply with the\nrequirement. We also interpret Paragraph 178.68-10 to state that in all 3 cylinders\nillustrated, the minimum wall thickness used for the stress calculation would be 0.142\ninches.\nWe are asking that you confirm our interpretations.\nTherefore, based upon affirmative answers by the Department of Transportation to Questions #1 and #2,\nit can be concluded that Cylinder #1 passed the tensile requirements of Specification 4E. This is due to\nthe actual weld tensile strength exceeding 30,000 psi, the apparent weld tensile strength exceeding\n35,324 psi and the cylinder sidewall tensile strength exceeded 35,324 psi.\nCylinder #2, passing the cylinder sidewall tensile strength requirements, failed the Specification 4E\nrequirements because the actual and apparent tensile weld strengths did not meet the minimum strength\nrequirements. Cylinder #3, passing the cylinder sidewall tensile strength and the actual weld tensile\nstrengtn requirement, tailed the Specification 4E requirements because the apparent weld tensile strength\ndid not meet the minimum weld tensile strength requirement.\nQUESTION #3\nProper measuring the thickness of tensile coupons has been a question that has been around for a\nnumber of years. This is extremely important when testing weld tensile coupons for aluminum cylinders\nmanufactured to Specification 4E for determination of actual tensile strength. I have enclosed\nAttachment B for your review. In reviewing the drawing, I have illustrated a typical tensile coupon for\n\n<<<PAGE 5>>>\n\nan aluminum weld. It should be noted that Worthington's experience in testing these welds will\nindicated that the fracture will occur in the heat affected zone of the weld not in the minimum\n\"thickness\" in the reduced area of the tensile coupon.\n•\nIt is the interpretation of Worthington, that the minimum thickness noted in the reduced\nsection of the coupon in this illustration would be 0.157 inches. This would then be\nused as the thickness multiplier in determination of the square inch area of the coupon..\nDepending on tensile testing equipment and technique of determining tensile strength,\nthe area would then be used in the equation to determine the actual weld tensile strength\nas described in Paragraph 178.68-17(a).\nWe are asking that you confirm our interpretation.\nThank you for your timely response to these questions. The answers to these questions are extremely\nimportant to new rule makings at the Department of Transportation and in turn, our reply to the new rule\nmakings. If I can be of any further assistance in this matter, please contact me at 614-438-3057.\nSincerely:\nSteven T. Geptry\nProject Engineer\nWorthington Cylinder Corporation\nattachments\n\n<<<PAGE 6>>>\n\n0,1424\n0.140\n0,1429 -\nD.142°\n0, 1480\n0,445\n0.M0\n0,1469.\n0. M0°\n0.145\n0.148\"\nCYLINDER • 1\nD.140\n0.149° -\nCYLINDER 02\n0.140-\n0.442\nCYLINDER +3\n0.145 -\n0. H0 .\n0.105\n0. Mage e\n0.I0|° -\n0.185 -\n0, M.\n0.к -\n0.147.\n0, 16° a\n0.1474→\n0.140%\n0.145\n0,1484 м\n0.150°\n0.168°\n0. 10°\n0,145\"\n0,142°\n0. 1484\n0,1470\n0,1c\n0.148\nATTACHMENT A\n\n<<<PAGE 7>>>\n\n0.500~\n0.500'\n0,500~\n0.500\"\n•HEAT AFFECTED ZONE\n00000\nATTACHMENT\nB\n\n<<<PAGE 8>>>\n\nColeman 8\nTHE COLEMAN COMPANY, INC.\nP.O. Box 2931\nWichita, Kansas 67201-2931","truncated":false,"body_characters":9389}