Vol. 337 No. 9 (2026)
DOI https://doi.org/10.18799/24131830/2026/9/5298
Thermocase: a panacea for protecting a well from permafrost or a dubious, expensive solution
Relevance. With the entry of oil and gas companies to the Far North with its harsh climatic and geocryological conditions, the issue of thermal protection of the wellhead part of production wells from the negative impact of permafrost is acute. High ice content and low temperatures of frozen rocks, their instability and fluidity during thawing, rupture pressure (reverse freezing) lead to deformations of the upper part of well structures, loss of longitudinal stability of their lining, failures and subsidence of well pads. Today, one of the main technical and technological solutions for preventing and/or minimizing such complications and accidents is seen and often used – the descent of a thermocase in the form of a heat-insulated direction or conductor. Aim. To carry out the analysis and assess the feasibility of using thermocases in solving the problem of combating permafrost in wells. Methods. Statistical and empirical methods, analysis and induction. Results and conclusions. The author analyzed and assessed the rationality of using thermocases in solving the general problem of combating permafrost in fields and, in particular, the issue of thermal protection of oil and gas wells. The use of thermocases to prevent complications is not a panacea for optimal thermal protection of a well – it is recommended to lower them only in special cases, justified by the assessment of surveys and special calculations at the design stage. Otherwise, their use will be an unnecessary waste of the customer's funds, which still does not exclude the risks of geological and technological complications and accidents associated with permafrost.
For citation: Korotkov S.A. Thermocase: a panacea for protecting a well from permafrost or a dubious expensive solution. Bulletin of the Tomsk Polytechnic University. Geo Assets Engineering, 2026, vol. 337, no. 9, pp. 57–64. http://doi.org/10.18799/24131830/2026/9/5298
Keywords:
thermocase, well, frozen rocks, well pad, deformation, casing pipe, thawing
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