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US 2024/0193315 A1Published application
Preserving wellbore integrity during carbon dioxide injection
AssigneeSchlumberger Technology Corporation
InventorsTerizhandur S. Ramakrishnan, Daniel Morrell
Life of this patent
Estimating the term…
Abstract
Embodiments presented provide for a method to negate debonding of the casing from a cement in a wellbore. In one embodiment, the cement around the casing is set with a sufficiently large residual compressive stress, preventing the deboning.
Claims17
A method of designing a wellbore with a cement residual compressive stress layer around a casing, comprising:
- obtaining data related to an open hole log for a wellbore in a field;
- performing a simulation for injection of a fluid within the field with a desired mass flow rate, a given surface temperature and anticipated designed perforations, the simulation computing downhole temperature on the wellbore;
- inferring densities of a mud and a cement slurry used within the field from a first mud specification and a first cement specification to be used with the wellbore;
- estimating a value of cement shrinkage (γc);
- computing a possible extent for shrinkage of material around the wellbore based upon the value of cement shrinkage (γc);
- evaluating the wellbore with the loading to determine if a case of plane stress or plane strain model governs the radial deformation of the wellbore, wherein:
- for a case of the plane stress governing the wellbore based upon the loading method steps of:
- setting a maximum brine height for the wellbore;
- calculating a plane stress coefficient value;
- calculating a value of stress and radial deformation for the wellbore;
- calculating a value of a height of slurry for the wellbore;
- reevaluating brine height if slurry height is at the bounds;
- are accomplished;
- and
- for a case of plane strain governing the wellbore based upon the loading;
- setting a maximum brine height for the wellbore;
- calculating a plane strain coefficient value;
- calculating a value of plane stress for the wellbore;
- calculating a value of a height of slurry for the wellbore;
- reevaluating brine height if slurry height is at the bounds;
- determining if a collapse of a casing occurs for the loading based upon the loading either of the plane stress or plane strain cases, wherein in an event of the collapse, one of a second casing specification and a second cement specification is chosen and a second simulation is run;
- and
- writing all input and calculated parameters to a non-volatile memory.
20 more elements
A method of designing a wellbore with a cement residual compressive stress layer around a casing, comprising:
- obtaining data related to an open hole log for a wellbore in a field;
- performing a simulation for injection of a fluid within the field with a desired mass flow rate, a given surface temperature and anticipated designed perforations, the simulation computing the downhole temperature on the wellbore;
- inferring densities of a mud and a cement slurry used within the field from a first mud specification and a first cement specification to be used with the wellbore;
- estimating a value of cement shrinkage γc
- computing a possible extent for shrinkage of material around the wellbore based upon the value of cement shrinkage (γc);
- evaluating the wellbore if a case of plane stress or plane strain model governs the wellbore deformation, wherein:
- for a case of the plane stress governing the wellbore based upon the loading method steps of:
- setting a maximum brine height for the wellbore;
- calculating a plane stress coefficient value;
- calculating a value of stress and radial strain for the wellbore;
- calculating a value of a height of slurry for the wellbore;
- recalculating brine height if the slurry height is at the bounds are accomplished;
- and
- for a case of plane strain governing the wellbore based upon the loading;
- setting a maximum brine height for the wellbore;
- calculating a plane strain coefficient value;
- calculating a value of stress and radial strain for the wellbore;
- calculating a value of a height of slurry for the wellbore;
- recalculating brine height if the slurry height is at the bounds
- determining if a collapse of a casing occurs for the loading based upon the loading either of the plane stress or plane strain case values, wherein in an event of the collapse, one of a second casing specification and a second cement specification is chosen and a second simulation is run;
- and
- writing all input and calculated parameters to a non-volatile memory.
19 more elements
Dependencies are inferred from the claim text.