Abstract A method for preventing deformation of the casing of a well bore hole extending into a reservoir interval within a subterranean hydrocarbon-bearing earth formation wherein such deformation is caused by the compaction of the reservoir interval in which unconsolidated sand therein compacts when the fluid pressure of the interval is reduced. A core sample is extracted from the interval containing a substantially undisturbed portion of unconsolidated sand typical of that contained in the interval. The extent of vertical compressibility of the cored sample is measured relative to its orientation within the reservoir interval and its lateral confinement in the configuration it exhibits under an isostatic compressive force equaling that existing within the interval. The vertical extent of the sand contained within the interval and the extent of reservoir interval compression that would result from a vertical compression of the sand contained in the reservoir interval by an amount corresponding to the measured compressibility of the core sample are determined. The portion of the well casing to be disposed against the interval is equipped with slip couplings adapted to provide an extent of slip having a selected degree of correspondence with the predetermined extent of reservoir interval compressibility.
Inventors
👤 Leo P Broussard
👤 Leon L Dickson Jr
👤 Wilhelmus J G Gardenier
Bibliographic Details
Application Number—
JurisdictionUS
Data Sourcegoogle_patents
Last Synchronized2026-11-03 22:00
CPC Classifications
E; E21; E21B; E21B17/00; E21B17/02; E21B17/08
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
28 words
The method of claim 1 including the step of fixing said casing firmly in position in said well borehole after equipping said well with said slip coupling means.
Claim 2
Dependent Claim
59 words
The method of claim 1 wherein the step of providing said well casing with slip coupling means including providing said casing with at least one slip coupling means disposed adjacent to substantially the top of the interval susceptible to compaction and at least one slip coupling means disposed adjacent to substantially the bottom of the interval susceptible to buckling.
Claim 3
Dependent Claim
65 words
The method of claim 1 wherein the step of measuring the extent of vertical compressibility of the sample comprises the step of placing both a vertical load and a side load equal in pressure on said sample, said vertical load being carried out by a piston and said side load being carried out by a fluid of a hardenable material adapted to withstand high temperatures.
Claim 4
Dependent Claim
28 words
The method of claim 4 wherein the step of placing a side load using a fluid includes the step of applying epoxy resin-saturated silicon carbide to said sample.
Claim 5
Dependent Claim
55 words
The method of claim 1 wherein the step of measuring the extent of vertical compressibility of the sample comprises the steps of: placing both a vertical load and a side load equal in pressure on said sample; increasing the pressure on said sample; and measuring the pressure at each increment of pressure on said sample.
Claim 6
Dependent Claim
65 words
The method of claim 6 including the step of determining the compressibility of said sample from the following equation Delta h/h c Delta sigma v where Delta h is the compaction of the core sample; h is the thickness of the core sample; c is the compressibility of the core sample; and Delta sigma v is the increase in effective stress of the core sample.