Local corrosion: calculation in oil field conditions (according to weight measurements)

Complications associated with a corrosive environment, according to Rosneft’s data at 01.01.2020, are among the prevailing at oil and gas production facilities and rank fourth among other factors complicating production – 12% the complicated mechanized wells. Failures due to corrosion are the second largest complicating factors. Based on the results of approbation, the article proposes a method for calculating the maximum rate of local carbon dioxide corrosion, applicable in oilfield conditions, including to complicated stocks of oil wells and pipelines of oil gathering systems. Based on the approbation results, a method for calculating the maximum rate of local carbon dioxide corrosion, applicable in oilfield conditions, including to complicated stocks of oil wells and oil-gathering pipelines systems is proposed in the article. The proposed technique is realizable according to the results one of «traditional» methods the corrosion monitoring - weight (or gravimetric). The approbation results and application possibility of the technique in the pilot tests process in assessing the protective ability of corrosion inhibitors and the selection of the effective dosages in relation to local damages, which are the main cause the oilfield equipment failures according the factor «Corrosive aggressiveness» (one of the complicating factors in terms of gradation, adopted in the Rosneft Company regulations). On practical examples the oilfield equipment operation, the results of corrosion monitoring and the summary statistics the corrosive stock of wells (using the example of an oil Company), the current situation with respect to this type of complication and relevance the issue under consideration is shown.

1. Markin, A. N., Nizamov, R. E. (2003). CO2-corrosion of oilfield equipment. Moscow: OAO VNIIOENG.

2. Markin, A. N., Nizamov, R. E., & Sukhoverkhov, S. V. (2011) Oilfield Chemistry: A Practical Guide: Vladivostok: Dal’nauka.

3. Markin, A. N. (1995). Prediction of carbon dioxide corrosion of steel under conditions of salt precipitation. Protection of Metals, 31(4), 394-400.

4. Markin, A. N., Sukhoverkhov, S. V., & Brikov, A. V. (2017). Local carbon dioxide corrosion of pipelines the oil gathering systems in Western Siberia fields. Neftepromyslovoye Delo, (1), 46-48.

5. Unified system of corrosion and ageing protection. Metals and alloys. Methods for determination of corrosion and corrosion resistance indices. (1986). GOST 9.908–85.

6. Markin, A. N., Markin, I. A. (n.d.). Calculation of maximum local corrosion rate in pipelines of oilgathering systems according to the data of weight measurements obtained by means of corrosion control samples. Neftepromyslovoye Delo, 12, 70-73.