Well production apparatus

Claim 2

In apparatus for producing warm fluid from a well through a plurality of sections of casing means which passes through a permafrost zone, the improvement comprising means defining a closed annular chamber along the length of each section of casing in said permafrost zone and capable of holding a vacuum therein, said chamber terminating a finite distance from either end of each casing section to provide an uninsulated space where one casing section is joined to another, and solid thermal insulation means extending across said uninsulated spaces between the ends of adjacent vacuum chambers so that said vacuum chambers serve as protective means for said insulation.

Claim 3

Apparatus according to claim 1 wherein said vacuum chambers contain in their interiors at least one layer of solid thermal insulation.

Claim 4

Apparatus according to claim 1 wherein there is a main wall for each casing section and said vacuum chambers extend outwardly therefrom, said vacuum chamber terminates a distance from either end of each casing section which is sufficient to allow working tools to be applied to said main wall without damaging said vacuum chamber, and annular solid thermal insulation extending around the outside of said main wall in said uninsulated space where one casing section is joined to another.

Claim 5

Apparatus according to claim 3 wherein said vacuum chambers contain in their interiors at least one layer of solid thermal insulation.

Claim 6

Apparatus according to claim 3 wherein said vacuum chambers contain in their interiors at least one layer of a gas diffusion barrier on at least one interior surface.

Claim 7

Apparatus according to claim 1 wherein there is a main wall for each casing section and said vacuum chamber extends inwardly therefrom, annular solid thermal insulation extends around the interior of said main wall in said uninsulated space where one casing section is joined to another, and means for protecting and holding said solid insulation in place.

Claim 8

Apparatus according to claim 6 wherein said vacuum chambers contain in their interiors at least one layer of solid thermal insulation.

Claim 9

Apparatus according to claim 6 wherein said means for holding said solid insulation in place comprises at least one member extending from the end of each vacuum chamber toward the nearest end of casing section, said members being spaced inwardly from said main wall.

Claim 10

Apparatus according to claim 6 wherein said vacuum chambers contain in their interiors at least one gas diffusion barrier on at least one interior surface.

Claim 11

Apparatus according to claim 6 wherein said vacuum chambers contain in their interiors at least one layer of solid thermal insulation and at least one gas diffusion barrier.

Claim 12

Apparatus according to claim 1 wherein each of said casing sections comprise two concentric, spaced apart inner and outer sleeves which define the inner and outer walls of said closed annular chamber, the first of said sleeves having fixed thereto at both ends a transition piece, an annular ring fixed to said first sleeve and having one edge extending laterally from said first sleeve toward the second and opposing sleeve, the second of said sleeves having a transition piece fixed thereto at both ends, and said outer edge of said ring being fixed to the second sleeve.

Claim 13

Apparatus according to claim 11 wherein said second sleeve transition piece is threaded for attachment to another casing section.

Claim 14

Apparatus according to claim 11 wherein said outer sleeve constitutes a portion of the main wall of the casing section, the first of said sleeves is the inner sleeve and has fixed thereto at both ends a transition piece which has an integral annular ring, said ring having its outer edge extending laterally from said inner sleeve toward the second and opposing sleeve, the second of said sleeves is the outer sleeve and has a threaded transition piece fixed thereto at both ends, and said outer edge of said ring is fixed to said outer sleeve.

Claim 15

Apparatus according to claim 11 wherein said inner sleeve constitutes a portion of the main wall of the casing section, the first of said sleeves is the outer sleeve and has fixed thereto at both ends a transition piece which has an integral annular ring, said ring having its outer edge extending laterally from said outer sleeve toward the second and opposing sleeve, the second of said sleeves is the inner sleeve and has a threaded transition piece fixed thereto at both ends, and said outer edge of said ring is fixed to said outer sleeve.

Claim 16

Apparatus according to claim 1 wherein said vacuum chambers contain in their interiors at least one gas diffusion barrier on at least one interior surface.

Claim 17

Apparatus according to claim 1 wherein said vacuum chambers contain in their interiors at least one layer of solid thermal insulation and at least one gas diffusion barrier.

Claim 18

In apparatus for producing warm fluid from a well through a plurality of sections of casing means which passes through a permafrost zone, the improvement comprising means defining a closed annular chamber along the length of each section of casing in said permafrost zone and capable of holding a vacuum therein, said chamber terminating a finite distance from either end of each casing section to provide an uninsulated space where one casing section is joined to another, solid thermal insulation means extending across said uninsulated spaces, a main wall for each casing section, said vacuum chamber extending inwardly from said main wall, said solid thermal insulation means being annular and extending around the interior of said main wall in said uninsulAted space where one casing section is joined to another, means for holding said solid insulation in place comprising at least one member extending from the end of each vacuum chamber toward the nearest end of the casing section, said members being spaced inwardly from said main wall, and an annular rubber insert between each end of said annular solid insulation and the adjacent end of the vacuum chamber.

Claim 19

In apparatus for producing warm fluid from a well through a plurality of sections of casing means which passes through a permafrost zone, the improvement comprising means defining a closed annular chamber along the length of each section of casing in said permafrost zone and capable of holding a vacuum therein, said chamber terminating a finite distance from either end of each casing section to provide an uninsulated space where one casing section is joined to another, solid thermal insulation means extending across said uninsulated spaces, a main wall for each casing section, said vacuum chamber extending inwardly from said main wall, said solid thermal insulation means being annular and extending around the interior of said main wall in said uninsulAted space where one casing section is joined to another, means for holding said solid insulation in place comprising at least one member extending from the end of each vacuum chamber toward the nearest end of the casing section, said members being spaced inwardly from said main wall, and an annular rubber insert between each end of said annular solid insulation and the adjacent end of the vacuum chamber.

Claim 20

In apparatus for producing warm fluid from a well through a plurality of sections of casing means which passes through a permafrost zone, the improvement comprising means defining a closed annular chamber along the length of each section of casing in said permafrost zone and capable of holding a vacuum therein, said chamber terminating a finite distance from either end of each casing section to provide an uninsulated space where one casing section is joined to another, solid thermal insulation means extending across said uninsulated spaces, said closed annular chamber being composed of two concentric spaced apart inner and outer sleeves, one of said sleeves constituting a portion of the main wall of the casing section, the first of said sleeves having fixed thereto at both ends an elongated transition spacer piece with an integral annular ring having its outer edge extending laterally therefrom toward the second and opposing sleeve, the second of said sleeves having a threaded spacer piece fixed thereto at both ends, said outer edge of said ring being fixed to the second sleeve, and extension member means carried by at least one of said spacer pieces and extends from the end of said spacer piece toward the nearest end of the casing section and spaced from said second sleeve to provide a socket for holding and protecting solid insulation inserted therein.

Claim 21

In apparatus for producing warm fluid from a well through a plurality of sections of casing means which passes through a permafrost zone, the improvement comprising means defining a closed annular chamber along the length of each section of casing in said permafrost zone and capable of holding a vacuum therein, said chamber terminating a finite distance from either end of each casing section to provide an uninsulated space where one casing section is joined to another, solid thermal insulation means extending across said uninsulated spaces, said closed annular chamber being composed of two concentric spaced apart inner and outer sleeves, one of said sleeves constituting a portion of the main wall of the casing section, the first of said sleeves having fixed thereto at both ends an elongated transition spacer piece with an integral annular ring having its outer edge extending laterally therefrom toward the second and opposing sleeve, the second of said sleeves having a threaded spacer piece fixed thereto at both ends, said outer edge of said ring being fixed to the second sleeve, and extension member means carried by at least one of said spacer pieces and extends from the end of said spacer piece toward the nearest end of the casing section and spaced from said second sleeve to provide a socket for holding and protecting solid insulation inserted therein.