{"operation":"document","citation":"PI-75-059","title":"Williams Brothers Engineering Company — Pipeline Safety Interpretation","source_type":"guidance","agency":"Pipeline and Hazardous Materials Safety Administration","status":"guidance","official":true,"published_on":"1975-12-12","effective_on":null,"summary":"PI-75-059 response to Williams Brothers Engineering Company concerning 192.103, 192.105, 192.111.","machine_formats":{"json":"https://regulus.evalyn.ai/document/phmsa-interpretation-pi-75-059.json","markdown":"https://regulus.evalyn.ai/document/phmsa-interpretation-pi-75-059.md"},"app_url":"https://regulus.evalyn.ai/document/phmsa-interpretation-pi-75-059","source_url":"https://www.phmsa.dot.gov/sites/phmsa.dot.gov/files/legacy/interpretations/Interpretation%20Files/Pipeline/1975/PI75059.pdf","body":"<<<PAGE 1>>>\n\nDec 12 1975\nMr. J. L. Williams\nWilliams Brothers Engineering Company\n6600 South Yale Avenue\nTulsa, OK 74136\nDear Mr. Williams:\nThis is with regard to the telephonic conversation between you and Mr. George L. Mocharko of\nthis Office concerning installing gas pipelines uncased under a hard surface road.\nYour interpretation of 49 CFR §192.103, §192.105, and §192.111(b)(2) is correct per your letter\nand attachments dated August 4, 1975.\nWe trust this adequately responds to your inquiry.\nSincerely,\nCesar DeLeon\nActing Director\nOffice of Pipeline\nSafety Operations\ndal\\192\\103\\75-12-12\n1\n\n<<<PAGE 2>>>\n\nJuly 31, 1975\nU.S. Department of Transportation\nOffice of Pipeline Safety\nWashington, D.C. 20590\nAttention: Mr. Ceasar De Leon\nSubject: Interpretation of Sub-Sections 192.103, 192.105, and 192.111(b)(2)\n_\nGentlemen:\nAttached is a print of our Figure 1-12.\nSub-sections 192.103, 192.105(a) and 192.111(b)(2) deal with external loads, design formula for\nsteel pipe, and design factor (F) for steel pipe.\nThe attached Figure 1-12 is an example that illustrates our interpretation of these sub-sections of\nthe code. Basically our interpretation is that for any given pipe size and wall thickness; and for a\ngiven design factor (F) the design pressure (internal pressure allowed) will be a lessor pressure\nwhen installed uncased under a hard surface road than when installation results in parallel\nencroachment on roads right-of-way.\nOur interpretation is based upon:\nA. 192.103\nPipe must be designed with sufficient wall thickness, or must be installed with adequate\nprotection to withstand anticipated external pressures and loads that will be imposed on\nthe pipe after installation.\ndal\\192\\103\\75-12-12\n2\n\n<<<PAGE 3>>>\n\nB. 192.105(a)\nt = C. Nominal wall thickness of the pipe in inches. ... additional wall thickness required\nfor concurrent external loads in accordance with 192.103 may not be included in\ncomputing design pressure.\nAPI RP 1102 Fourth Edition, September 1968 - Recommended Practice for Liquid\nPetroleum Pipelines Crossing Railroads and Highways\nParagraphs 3.1 a, b, and c.\nUsing this information Figure 1-12 has been constructed and indicates that for 12.75\" O.D. x\n.255\" W.T., X-60 pipe the design pressure would be limited to 1350 psig for an uncased road\ncrossing of a hard surfaced road in a Class 1 location, while the design pressure for the same pipe\nwould be 1440 psig for parallel encroachment on highways or public streets in a Class 1 location.\nPlease advise if you concur with our interpretation of the regulations.\nYour prompt consideration of this matter will be appreciated.\nYours very truly,\nWILLIAMS BROTHERS ENGINEERING COMPANY\nJ. L. Williams\nAttachment\ndal\\192\\103\\75-12-12\n3","truncated":false,"body_characters":2727}