# US 8,783,362 B2 · Bellows type adjustable casing > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,783,362 B2 - Document ID: US8783362B2 - Status: Granted - Kind: B2 - Application number: 12/957,163 - Filed: 2010-11-30 - Published: 2011-03-24 - Granted: 2014-07-22 - Earliest claimed: 2008-12-11 - Assignees: Vetco Gray Inc. - Applicants: Frank C. Adamek - Inventors: Frank C. Adamek - Web page: https://patentgrep.com/patent/US8783362B2 ## CPC - E21B 17/01: Risers - E21B 17/07: Telescoping joints for varying drill string lengths; Shock absorbers - E21B 17/08: Casing joints - E21B 19/002: {specially adapted for underwater drilling (E21B19/09, E21B19/143 take precedence)} - E21B 19/004: {supporting a riser from a drilling or production platform} - E21B: EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS ## Abstract A subsea assembly for producing fluids from a well having a casing string in the well supported with a hanger on an upper end. Cement is in a portion of an annulus between the casing string and walls of the well, thereby leaving segment of the casing string unsupported in the well. A motion compensating element is coaxially provided in the unsupported segment of the casing string to absorb axial expansion and/or contraction that may occur in the unsupported segment of the casing string. ## Claims ### Claim 1 A subsea assembly for carrying fluids from a subsea wellbore comprising: an outer tubular inserted in an opening of the wellbore; a hanger mounted on a lower end of the outer tubular; a casing string depending from the hanger into the wellbore; and an axially expandable and compensating member provided along a portion of the casing string having a wall with undulations that comprise a series of slots along a length of the wall alternatingly formed about an inner circumference and about an outer circumference of the wall, each slot lying in a plane substantially perpendicular to an axis of the compensating member, the slots defining a series of cantilevers along a length of the body that are bendable when the body is axially compressed and that are bendable when the body is axially elongated, so that when casing above the compensating member is supported in tension the body transmits the tension to the casing below the compensating member. ### Claim 2 (depends on 1) The subsea assembly of claim 1, wherein the compensating member axially expands and contracts a greater amount per linear increment than the casing string. ### Claim 3 (depends on 1) The subsea assembly of claim 1, wherein the cantilevers in the wall comprise annular foldable segments coaxially stacked along an axis of the compensating member. ### Claim 4 (depends on 3) The subsea assembly of claim 3, wherein the foldable segments have an “S” shaped cross section. ### Claim 5 (depends on 1) The assembly of claim 1, wherein the slots in the wall comprise helical grooves. ### Claim 6 (depends on 1) The subsea assembly of claim 1, further comprising a support sleeve circumscribing at least a portion of the compensating member and that is free of the tension transmitted through the compensating member. ### Claim 7 (depends on 1) The subsea assembly of claim 1, wherein the outer tubular comprises a conductor pipe mounted in a wellhead housing set on the sea surface. ### Claim 8 (depends on 1) The subsea assembly of claim 1, wherein the outer tubular comprises a conductor pipe mounted to the sea surface and the hanger is below a mudline on the seafloor. ### Claim 9 A subsea assembly for carrying fluids from a subsea wellbore comprising: a wellhead assembly comprising a production tree mounted on a wellhead housing a hanger mounted within the wellhead housing; a casing string depending from the hanger into the wellbore; and a compensating member that is axially expandable and contractible provided along is portion of the casing string and having a body with a wall that includes undulations comprising a series of slots along a length of the wall alternatingly formed about an inner circumference and about an outer circumference of the wall, each slot lying in a plane substantially perpendicular to an axis of the compensating member, the slots defining a series of cantilevers along a length of the body that are bendable when the body is axially compressed and that are bendable when the body is axially elongated, so that when casing above the compensating member is supported in tension the body transmits the tension to the casing below the compensating member. ### Claim 10 (depends on 9) The subsea assembly of claim 9, wherein the compensating member further comprises a set of threads on each end of the body for connecting to upper and lower sections of the casing string wherein the wall has a greater thickness between the inner and outer diameter surfaces than portions of the body containing the threads. ### Claim 11 A compensating casing sub mechanically coupleable between a tubular member and a second member, comprising: a tubular body having a steel wall and an axis; a first end adapted to be affixed to an end of the tubular member; a second end adapted to be affixed to an end of the second member; a series of compressible segments integrally formed in the wall of the body circumscribing the axis and sequentially arranged along a length of the body to enable the body to be compressed between the tubular member and the second member to absorb thermal expansion of the tubular member; and wherein the compressible segments are defined by a series of helical slots along a length of the wall alternatingly formed about an inner circumference and about an outer circumference of the wall, each helical slot lying in a plane substantially perpendicular to an axis of the compensating member, the helical slots defining a series of cantilevers along a length of the body that are bendable when the body is axially compressed and bendable when the body is axially elongated. ### Claim 12 (depends on 11) The compensating casing sub of claim 11, wherein the second member is adapted to be secured to a wellhead member and compression of the compensating casing sub reduces stress between the second member and the wellhead member due to thermal expansion of the tubular member.