Inorder to confirm calculated values of operating production rates for new wells, flow coefficients A and B, draw-down pressure it is crucial to ensure the variation range of production rate reaching the design value at the stage of well development and initial gas dynamic testing at steady flow modes.
Increased volume and improved quality of received data at the stage of well drilling and development allows to enhance reliability of design solutions and avoid time and financial expenditures for additional survey.
Upon construction of exploration and high-rate production wells in offshore fields it is not possible to conduct full-scale initial gas dynamic testing in course of well development. Therefore, the required accuracy of forecast calculation of well operation mode and, subsequently, customization of the hydrodynamic model, cannot be assured to the full extent. Gas dynamic well testing offshore is limited due to specific nature of work performance and specifications of development units of semisubmersible drilling rigs.
The limits are primarily associated with the throughput capacity of the utilized separation equipment of semisubmersible drilling rig (maximum allowable rate), well design and the time allowed for well development.
Kirinskoye gas condensate field is located in the shelf of the Sea of Okhotsk along the north-east coast of the Sakhalin is land within Sakhalin-3 project Kirinskiy prospective site. The field is the first hydrocarbon development site of Gazprom in the shelf of the Russian Federation where subsea development system was utilized, which demands higher standards for development project design performance control.
The construction of production wells was being conducted with the utilization of semisubmersible rigs Polyarnaya Zvezda (Polar Star) and Severnoye Siyaniye (Northern Lights). In 2017 two gas condensate production wells were completely constructed and temporarily shut down until connection to the subsea gathering and transportation system for produced formation fluid.
During exploration drilling of the wells in Kirinskoye gas condensate field gas dynamic testing was carried out selectively and cannot be used to the full extent for forecasting and correlation with the results of gas dynamic testing of production wells.