INVESTIGATIONS OF WELDED CONNECTIONS OF THE BASIC TUBE DESIGN OF DRILLING RISER ABR-G

Abstract

Background. This article deals with the problem of ensuring the operability of the main pipe structures of the riser. Raiser is one of the main components in the development of oil and gas fields on the shelf and sea. There are different types of risers, which are used depending on technological tasks. The system of the riser is an intermediate link between the offshore platform and the wellhead on the seabed. Raiser isolates the well from the environment, provides a closed circulation of the drilling fluid, serves as a channel for drilling and casing pipes, geophysical equipment, and also manages the blowout device components and connectors through hydraulic and service pipelines laid along the entire length of the riser. The design of the low-pressure riser is the concept of a 21-inch pipe with welded flange connections of the «Vetco» type. Raiser has two hydraulic lines, two lines of jammingthrottling and one booster. A typical material for the construction of the pipe structure of the riser is steel with good plastic properties, however, as the depth of the sea increases, exploration and development of deposits is becoming a matter of the possibility of using titanium and aluminum alloys, as well as composite materials. This is due to the in- crease in weight of equipment as the depth in- creases - a consequence of approaching the weight of the structure to critical strength val- ues. Aims and Objectives The main objective of the research is the analysis of displacement characteristics of oil wells and oil fields. Methods Samples of welded joints were subjected on the tensile machine INSTON 5900 Series. Alloy was analyzed for low-cycle fatigue, on a test machine PSA, 100 kN (Schenck Trebel Corporation). Rezults Based on the results of the conducted studies, it was concluded that the technology of welding manual arc welding does not provide the necessary strength characteristics required for operation of the ADB-G riser. The strength of the welded joint was 0.60-0.61σ from the yield strength of the base metal, while the reference values were 0.98σ.