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1. #Grease monkey coupons safety and emissions driver#
2. #Grease monkey coupons safety and emissions crack#

#Grease monkey coupons safety and emissions crack#

In the absence of hydrogen, (linear elastic) fracture mechanics (LEFM) theory predicts that a crack in a metallic component will grow when the stress intensity factor (SIF) at the crack tip reaches an “intrinsic” material property – the fracture toughness, noted K IC.

#Grease monkey coupons safety and emissions driver#

The main driver for the increased research around modeling of hydrogen-assisted cracking (HAC) of metals is certainly the so-called subcritical cracking.

These types of damages can be triggered at relatively low stress levels and pose serious threat to structural integrity, thus the importance of having reliable integrity assessment and predictive models. It is well known that steels used in the oil and gas industry can suffer from different forms of hydrogen embrittlement (HE), among blistering, hydrogen-induced cracking (HIC)/stress-oriented hydrogen induced cracking (SOHIC), sulfide stress cracking (SSC), and stress corrosion cracking (SCC). These reservoirs, which were considered non-profitable for production, are nowadays being reconsidered owing to the growing world’s energy demands. The general tendency worldwide is the increased sourness of produced oil and gas reservoirs reaching up to 20% H 2S content in some regions of the world (e.g.

Finally, the challenges that hinder the application of existing models to component integrity assessment and remaining life prediction are discussed with respect to identification of model parameters and limitations of the fracture similitude, which paves the way to new directions for further research. Emerging multiscale approaches are also discussed, and studies relative to HE in metals and especially steels are presented. Existing continuum models are compared in terms of their ability to predict the threshold stress intensity factor and crack growth rate accounting for the complex couplings between hydrogen transport and accumulation at the fracture process zone, local embrittlement, and subsequent fracture. The present manuscript reviews state-of-the art models of hydrogen-assisted cracking (HAC) with potential for application to remaining life prediction of oil and gas components susceptible to various forms of hydrogen embrittlement (HE), namely, hydrogen-induced cracking (HIC), sulfide stress cracking (SSC), and HE-controlled stress corrosion cracking (SCC).