Corrosion and the role of structural aluminum alloys in the construction of oil and gas wells

This paper presents the main research results and examples of structural aluminium alloys (SAA) effective use in the oil and gas wells construction onshore and offshore. The known application cases are drill pipes, tubing and casing. Competitive properties of SAA for hydrocarbons exploration and production were identified as strength-to-weight ratio, high total corrosion resistance, including dissolved hydrogen sulphide and carbon dioxide, absence of cold-shortness effect. The issues with the natural properties of aluminum alloys requiring process and structural corrections were addressed as well. Technical solutions to neutralize characteristics, which limited SAA use in the wells construction have been advised and examples of implementation shown. Among them, technology of surface layers modification, coatings and methods of isolation contacts with other material, system of integrated corrosion protection and optimization of operation environment. Aluminum drilling riser (ADR) is one of the most striking examples of the object from SAA. ADR presents integrated solution of SAA application problems. Finally, SAA could successfully address well construction corrosion issues

EXPERIENCE IN THE DEVELOPMENT AND USE OF ALUMINUM ALLOY CASING FOR CONDITIONS OF HIGH CONTENT OF ACID GASES IN FORMATION FLUIDS

When selecting a casing material for fields with a high content of H2S and CO2, it is recommended to use specialized corrosion-resistant tubulars with high content of chrome of the Sanicro 29 type. The high cost of the material can be critical for the project economy. A promising approach for these problems elimination could be the application of aluminium alloy casing pipes. They are remain inert to corrosion even if the formation environment is fully saturated with H2S and/or CO2. They are also lightweight, have high strength-to-weight ratio, and thus decrease the existing tensions in the string and reduce well construction costs

Protection enhancing of threaded connections of light-alloy drill pipes against contact corrosion

When using light-alloy drill pipes (LAIDP) with steel tool joints, the development of contact corrosion is observed under certain operating conditions. The value of corrosion mainly depends on the difference in electrochemical potential (ECP) of the contacting metals. One of the effective methods for increasing the corrosion resistance of aluminum alloys is the micro-arc oxidation (MAO) method. This is an electrochemical process in combination with micro-arc-discharges phenomena at the anode-electrolyte border, which allows forming ceramic coatings of aluminum oxides on the surface, including its high-toughness and wear-resistant phase - α-Al2O3 (corundum). MAO-technology is a highly efficient and environmentally friendly process. At the forming of such a coating on the threaded part and in the tool joint zone of the pipe, a barrier for contact corrosion between the steel tool joint and the surface of the aluminum pipe is created. In this work, contact corrosion on samples in a pair of 1953T1 aluminum alloy - 40KhN2MA steel in a 5% NaCl solution at 80 °C was investigated. The data obtained showed the effectiveness of using protective MAO-coating to reduce contact corrosion and increase the reliability of the tool joint threaded connection of LAIDP

Abstracts of The Second Eurasian RISK-2020 Conference and Symposium

This abstract book contains abstracts of the various research ideas presented at The Second Eurasian RISK-2020 Conference and Symposium.The RISK-2020 Conference and Symposium served as a perfect venue for practitioners, engineers, researchers, scientists, managers and decision-makers from all over the world to exchange ideas and technology about the latest innovation developments dealing with risk minimization