{"product_id":"pr723-253819-r01-critical-review-of-im-1-08-reports-white-paper-2","title":"PR723-253819-R01 Critical Review of IM-1-08 Reports White Paper","description":"\u003cp\u003eThis document is a peer review of two recent reports from PRCI Project IM-1-08, which proposes new minimum fracture toughness requirements to comply with PHMSA Mega Rule RIN1 -- 192.712. The original reports present practical recommendations for Charpy V-Notch (CVN) toughness values for vintage and modern pipeline material categories, offering some relief from the exceedingly conservative default toughness mandates in 49CFR192.712. However, these re-ports contain a controversial recommendation that the authors believe run counter to the consensus of published literature.\u003c\/p\u003e\n\n\u003cp\u003eSpecifically, the authors take issue with proposed toughness adjustments in IM-1-08, in which fracture toughness is assumed to decrease monotonically with relative crack depth, at, down to zero a\/t at=0.9. Empirical data for vintage pipe joints, both burst tests and prior failures, show no evidence of a significant drop in toughness for deep cracks. Accordingly, the present authors conclude that the IM-1-08 recommendations concerning crack depth effects on fracture toughness lack technical justification.\u003c\/p\u003e\n\n\u003cp\u003eThe present authors also investigated the influence of pipe metal temperature on the pressure capacity of LF-ERW pipe within the range of 0 to 70F. The study incorporated Monte Carlo simulations that accounted for variability in fracture toughness (including constraint effects), tensile properties, flaw dimensions, and flaw location (i.e., bond line versus heat-affected zone).\u003c\/p\u003e\n\n\u003cp\u003eThe target audience for this report includes pipeline operators, regulators, subject matter experts, and researchers with an interest in the crack threat. The original PHMSA Mega Rule RIN1 - 192.712 has a number of well-documented shortcomings, so there is a very strong need to modify this regulation. The present report is an important companion to the original IM-1-08 reports because it presents a different perspective on toughness rules and offers improvements on the original authors' recommendations.\u003c\/p\u003e","brand":"PRCI Store","offers":[{"title":"Default Title","offer_id":44367542616142,"sku":"332362","price":50.0,"currency_code":"USD","in_stock":true}],"url":"https:\/\/prci-store.myshopify.com\/products\/pr723-253819-r01-critical-review-of-im-1-08-reports-white-paper-2","provider":"PRCI Store","version":"1.0","type":"link"}