Slurry pipeline systems are used to process and transport mined ore and tailings in the oil and gas and mining industries. The handling processing and transporting of these slurries result in significant pipe wall material losses or wear. For the most widely used material carbon steel these losses are attributed to the combined effects of erosion/abrasion and corrosion due to the exposure of pipe wall materials to an aerated mixture of solids and liquids. In an attempt to mitigate this challenge some end-users such as mined oil sands operators have adopted polymer based pipe liner which basically only experiences erosion or abrasion damage. Models can be used as a predictive tool to optimize slurry design and processes material selection and/or even used as a tool for preventive maintenance. They are also being employed for technology assessment and product evaluation. These benefits are realized if the models are based on underlying mechanics or phenomena in the real systems. Unarguably there are a significant number of models for erosion-corrosion especially erosive wear. These models have a varying degree of accuracy which is partly due to the fact that most of them are based on some degree of empiricism and may lack accurate information on key parameters. Unfortunately models for wear which usually occurs in dense slurries are very limited despite most slurry applications fall under this category. As part of a broader wear model development project at our company this work focuses on validations of existing abrasive wear and/or abrasive-corrosion models. This work adopts computational fluid dynamic (CFD) as a tool to model abrasive wear and/or abrasion-corrosion in horizontal pipeline dense slurries. These CFD results will be compared with previously acquired wear data in our pilot-scale slurry flow loop for mild and dual-phase stainless steels pipe spools. The model performance will be presented and discussed with recommendations for future works.Key words: Wear; Pipeline; Slurry; Oil sands; Abrasion-corrosion; Flow Loop; CFD; modeling

Cold worked Alloy 28 (UNS N08028) and Alloy 29 (UNS N08029) have been successfully used as Oil Country Tubular Goods (OCTG) in H2S-containing downhole applications. Laboratory testing showed high stress corrosion cracking (SCC) resistance of these alloys in sour conditions outside of ISO limits for 4c type materials where Alloy 828 Alloy 28 and Alloy 29 belong to. Recently a similar study found in literature showed comparable results between cold worked Alloy 28 and Alloy 825 (UNS N08825). Alloy 28 Alloy 29 and Alloy 825 in annealed conditions belong to 4a type materials which have higher SCC resistance compared to the cold worked materials. Compared to Alloy 825 Alloy 29 is arelatively new material which has been introduced in control line and chemical injection line applications. However corrosion testing data is not always available for these materials in annealed conditions. ISO 15156-3 has no environmental limits for the 4a type materials. This work aimed at to provide pitting corrosion resistance data on the full-size tube materials for control line and chemical injection line in annealed conditions.Pitting corrosion resistance of Alloy 29 and Alloy 825 has been determined by critical pitting temperature (CPT) per ASTM G150 on full-size seamless tubes in annealed condition for control line and chemical injection applications. The effect of pitting resistance equivalent (PRE) has been studied by using Alloy 825 Alloy 316L (UNS S31603) in control line dimensions. Alloy 28 and Alloy 29 in cold worked condition for OCTG application were also included.The CPT was 70°C for Alloy 29 and 30 ~ 45°C for Alloy 825 which was mainly dependent on pitting resistant equivalent (PRE) of the materials. Alloy 29 and Alloy 825 belong to same category 4a and 4c type nickel-based alloys defined by ISO15156-3 for down-hole applications. Because Alloy 29 has higher PRE and lower Ni content compared to Alloy 825 Alloy 29 can be considered as a cost-saving material for control line and chemical injection line applications.

Precipitation Hardened (PH) Ni-based alloys have proved to be sensitive to HydrogenInduced Stress Cracking (HISC) and HISC related failures in the Oil and Gas industry havebeen experienced in the case of UNS N07718 UNS N07725 and UNS N07716.Slow Strain Rate Tensile (SSRT) tests conducted under cathodic polarization gaveencouraging results as a means to evaluate HISC resistance when applied to UNS N07718better enabling the discrimination of acceptable and unacceptable microstructures as accordingto API 6A CRA. As a consequence an extensive test program was launched on several PH Nigrades a program both initiated and sponsored by 7(8) Oil & Gas Companies. The main objectives of this program were to develop a test method to allow for the evaluation of HISC resistance inorder to rank materials and possibly define acceptance criteria for each material and alsoto better understand the relationship between microstructure and HISC resistance. Twenty-eightindustrial Heats of PH Ni Alloys of eight material grades were fully characterized(microstructure mechanical properties) and evaluated using the SSRT test method underapplied cathodic polarization. The yield strength of the materials tested was in the range120 to 160 ksi. The quantitative susceptibility of the materials to HISC was established using the plastic elongation epCP and the plastic elongation ratio epCP/ epinert. Test results showed that some PH Alloys that exhibited acceptable microstructures in accordance with API 6ACRA did not necessarily exhibit high plastic elongation ratios. The need to implement HISC related tests in the selection of PH Ni base alloys for Oil and Gas applications is indicated.