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Annulus (oil well)

About: Annulus (oil well) is a research topic. Over the lifetime, 2901 publications have been published within this topic receiving 39085 citations.


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Patent
29 Sep 1995
TL;DR: A rotary drill bit for use in drilling holes in subsurface formations comprises a bit body having a leading face and a gauge region, a number of blades formed on the leading face of the bit and extending outwardly away from the axis of a bit so as to define between the blades the number of fluid channels leading towards the gauge region as discussed by the authors.
Abstract: A rotary drill bit for use in drilling holes in subsurface formations comprises a bit body having a leading face and a gauge region, a number of blades formed on the leading face of the bit and extending outwardly away from the axis of the bit so as to define between the blades a number of fluid channels leading towards the gauge region, a number of cutting elements mounted side-by-side along each blade, and a number of nozzles in the bit body for supplying drilling fluid to the fluid channels for cleaning and cooling the cutting elements. In each of the fluid channels, adjacent the gauge region, is an opening into an enclosed passage which passes internally through the bit body to an outlet which, in use, communicates with the annulus between the drill string and the wall of the borehole being drilled. The gauge region of the drill bit comprises a substantially continuous bearing surface which extends around the whole of the gauge region.

720 citations

Patent
21 Sep 1995
TL;DR: A method for assembling concentric coiled tubing, with insulation, and apparatus in combination with the insulated coiled tube composite for heat assisted production of hydrocarbons and minerals from a wellbore is described in this article.
Abstract: A coiled tubing composite comprising insulated coiled tubing, concentric coiled tubing and insulated concentric coil tubing, including structure with centralizers and providing an annulus for insulation. The invention includes a method for assembling concentric coiled tubing, with insulation, and apparatus in combination with the insulated coiled tubing composite for heat assisted production of hydrocarbons and minerals from a wellbore.

413 citations

Patent
19 Jan 2007
TL;DR: In this paper, the authors present an apparatus and methods for forming an annular isolator in a borehole after installation of production tubing, where reaction chemicals are carried in the tubing and injected into the annulus to react with each other and ambient fluids to increase in volume and harden into annular seal.
Abstract: The present disclosure addressed apparatus and methods for forming an annular isolator in a borehole after installation of production tubing. Annular seal means are carried in or on production tubing as it is run into a borehole. In conjunction with expansion of the tubing, the seal is deployed to form an annular isolator. An inflatable element carried on the tubing may be inflated with a fluid carried in the tubing and forced into the inflatable element during expansion of the tubing. Reactive chemicals may be carried in the tubing and injected into the annulus to react with each other and ambient fluids to increase in volume and harden into an annular seal. An elastomeric sleeve, ring or band carried on the tubing may be expanded into contact with a borehole wall and may have its radial dimension increased in conjunction with tubing expansion to form an annular isolator.

352 citations

Patent
10 Dec 1992
TL;DR: A steam, carbon dioxide, or solvent injection method is used in combination with a cased well completed to have an upper vertical section, a lower vertical section and a horizontal section which connects the two vertical sections as mentioned in this paper.
Abstract: A steam, carbon dioxide, or solvent injection method is used in combination with a cased well completed to have an upper vertical section, a lower vertical section and a horizontal section which connects the two vertical sections Steam, carbon dioxide, or solvent is injected down tubing in the well and through perforations near the lower portion of the lower vertical section of the well and into an oil-bearing formation that is penetrated by the well Oil is produced from the formation via perforations in the casing in the upper vertical section and thence upward through the annulus formed between the tubing and the casing to the surface of the earth for recovery

270 citations

Journal ArticleDOI
TL;DR: In this paper, the authors present an approach to estimate wellbore fluid temperature during steady-state two-phase flow using thermal diffusivity equation and the effect of both conductive and convective heat transport for the well-bore/formation system.
Abstract: Wellbore fluid temperature is governed by the rate of heat loss from the wellbore to the surrounding formation, which in turn is a function of depth and production/injection time The authors present an approach to estimate wellbore fluid temperature during steady-state two-phase flow The method incorporates a new solution of the thermal diffusivity equation and the effect of both conductive and convective heat transport for the wellbore/formation system For the multiphase flow in the wellbore, the Hasan-Kabir model has been adapted, although other mechanistic models may be used A field example is used to illustrate the fluid temperature calculation procedure and shows the importance of accounting for convection in the tubing/casing annulus A sensitivity study shows that significant differences exist between the predicted wellhead temperature and the formation surface temperature and that the fluid temperature gradient is nonlinear This study further shows that increased free gas lowers the wellhead temperature as a result of the Joule-Thompson effect In such cases, the expression for fluid temperature developed earlier for single-phase flow should not be applied when multiphase flow is encountered An appropriate expression is presented in this work for wellbores producing multiphase fluids

252 citations


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Performance
Metrics
No. of papers in the topic in previous years
YearPapers
20224
202175
2020132
2019140
2018145
2017113