Louisiana Administrative Code › Title 43 - NATURAL RESOURCES › Part XIII - Office of Conservation-Pipeline Safety › Subpart 3 - Transportation of Natural Gas or Other Gas by Pipeline: Minimum Safety Standards [49 CFR Part 192] › Chapter 27 - Operations [49 CFR Part 192 Subpart L] › Section XIII-2732 - Engineering Critical Assessment for Maximum Allowable Operating Pressure Reconfirmation: Onshore Steel Transmission Pipelines. [49 CFR 192.632]

Current through Register Vol. 50, No. 6, June 20, 2024
A. When an operator
				  conducts an MAOP reconfirmation in accordance with §2724.C 3"Method 3"
				  using an ECA to establish the material strength and MAOP of the pipeline
				  segment, the ECA must comply with the requirements of this Section. The ECA
				  must assess: threats; loadings and operational circumstances relevant to those
				  threats, including along the pipeline right-of way; outcomes of the threat
				  assessment; relevant mechanical and fracture properties; in-service degradation
				  or failure processes; and initial and final defect size relevance. The ECA must
				  quantify the interacting effects of threats on any defect in the pipeline.
				  [49
				  CFR 192.632]
B. ECA Analysis [49
				  CFR 192.632(a)]
1. The material properties required to
				  perform an ECA analysis in accordance with this Section are as follows:
				  diameter, wall thickness, seam type, grade (minimum yield strength and ultimate
				  tensile strength), and Charpy v-notch toughness values based upon the lowest
				  operational temperatures, if applicable. If any material properties required to
				  perform an ECA for any pipeline segment in accordance with this Section are not
				  documented in traceable, verifiable and complete records, an operator must use
				  conservative assumptions and include the pipeline segment in its program to
				  verify the undocumented information in accordance with §2707 The ECA must
				  integrate, analyze, and account for the material properties, the results of all
				  tests, direct examinations, destructive tests, and assessments performed in
				  accordance with this Section, along with other pertinent information related to
				  pipeline integrity, including close interval surveys, coating surveys,
				  interference surveys required by Chapter 21 of this Subpart, cause analyses of
				  prior incidents, prior pressure test leaks and failures, other leaks, pipe
				  inspections, and prior integrity assessments, including those required by
				  §§2717, 2910, and Chapter 33 of this Subpart. [49
				  CFR 192.632(a)(1)]
2. The ECA must analyze and determine the
				  predicted failure pressure for the defect being assessed using procedures that
				  implement the appropriate failure criteria and justification as follows.
				  [49
				  CFR 192.632(a)(2)]
a. The ECA must analyze any cracks or
				  crack-like defects remaining in the pipe, or that could remain in the pipe, to
				  determine the predicted failure pressure of each defect in accordance with
				  §
													2912 [49
				  CFR
				  192.632(a)(2)(i)]
b. The ECA must analyze any metal loss
				  defects not associated with a dent, including corrosion, gouges, scrapes or
				  other metal loss defects that could remain in the pipe, to determine the
				  predicted failure pressure. ASME/ANSI B31G (incorporated by reference, see
				  §507) or R-STRENG (incorporated by reference, see §507) must be used
				  for corrosion defects. Both procedures and their analysis apply to corroded
				  regions that do not penetrate the pipe wall over 80 percent of the wall
				  thickness and are subject to the limitations prescribed in the equations
				  procedures. The ECA must use conservative assumptions for metal loss dimensions
				  (length, width, and depth). [49
				  CFR
				  192.632(a)(2)(ii)]
c. When determining the predicted failure
				  pressure for gouges, scrapes, selective seam weld corrosion, crack-related
				  defects, or any defect within a dent, appropriate failure criteria and
				  justification of the criteria must be used and documented. [49
				  CFR
				  192.632(a)(2)(iii)]
d. If SMYS or actual material yield and
				  ultimate tensile strength is not known or not documented by traceable,
				  verifiable, and complete records, then the operator must assume 30,000 p.s.i.
				  or determine the material properties using §2707 [49
				  CFR
				  192.632(a)(2)(iv)]
3. The ECA must analyze the
				  interaction of defects to conservatively determine the most limiting predicted
				  failure pressure. Examples include, but are not limited to, cracks in or near
				  locations with corrosion metal loss, dents with gouges or other metal loss, or
				  cracks in or near dents or other deformation damage. The ECA must document all
				  evaluations and any assumptions used in the ECA process. [49
				  CFR 192.632(a)(3)]
4. The MAOP must be established at the lowest
				  predicted failure pressure for any known or postulated defect, or interacting
				  defects, remaining in the pipe divided by the greater of 1.25 or the applicable
				  factor listed in
				  §2719.A.2.b [49
				  CFR 192.632(a)(4)]