Experimental erosion/corrosion modelling was performed on C-Mn steels and corrosion resistant alloys commonly used in petroleum production. A graded commercial sand of 50-30b pm size range, similar to sands produced from typical oil/gas fields was used to simulate the erosive medium. The experimental conditions such as the sand flux, particle velocity, pressure and temperature, were chosen based on typical field operating conditions for corrosion, erosion and erosion-corrosion tests imposed on the materials. The corrosion environment was created by feeding in CO2 gas with atomised water into the test chamber. A centrifugal erosion rig (45) with necessary modifications to suit wet and dry test conditions was used in the experiments. The rig was capable of generating over 150 m/s particle velocity and could operate at high temperatures to generate consistent results. Results show that (a) there was a soft thin layer of corrosion products formed on the C-Mn specimens even at 20°C which can easily be removed by the impacting particles , (b) the scale growth rate kinetics were found to be parabolic and vary between 8x10-3 pun'/h to 50x10-3 iim2/h depending on the material and temperature, (c) the process of metal recession consists of the removal and regrowth of soft corrosion scale at low flux and low velocity, and erosion of substrate at high flux and high velocity, (d) the erosion-corrosion rates were found to vary between 2- 30 times over the pure erosion rates under the same conditions, depending on the sand flux, particle velocity and temperature. An existing computer simulation model (46) was used to simulate the conditions observed from the experiments. Some improvements were incorporated into the programme and the final model is capable of predicting the erosion and erosion-corrosion rates applicable to petroleum production.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:512737 |
| Date | January 1994 |
| Creators | Hamzah, Razali Bin |
| Contributors | Strutt, J. E. ; Stephenson, David J. |
| Publisher | Cranfield University |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://dspace.lib.cranfield.ac.uk/handle/1826/3630 |
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