Insulated casing assembly
AssigneeGeneral Electric Company
InventorsEdgar O. Stephenson, John M. Kohl, Charles R. Cunningham
Life of this patent
Estimating the term…
Abstract
An insulated casing assembly for use in injecting steam into wells, comprising a plurality of interconnected casings, each casing having outer and inner tubular sections, an annular spacing between the two sections containing multilayered thermal insulation enveloped in a low conductivity gas, and tubular bellows connecting and allowing relative movement between the corresponding ends of the two inner sections. A leak-proof connection between adjacent casings includes a diffuser sleeve fitted tightly over the ends of adjacent inner tubular sections, a filler ring fitted on the diffuser sleeve and disposed between adjacent outer tubular sections, and a threaded coupling screwed onto threaded ends of outer tubular sections of adjacent casings.
Claims19
An insulated casing assembly comprising;
- (a) a pair of coaxially arranged casings, each casing comprising radially spaced inner and outer tubular sections defining an annular space therebetween, and expandible sealing means extending from a point spaced inward from the end of each said inner tubular section in an axial direction to said outer tubular section thereby forming an axially extending cavity around each said inner tubular section;
- (b) a sleeve tightly fitting over the opposed ends of the inner tubular sections and extending into said axially extending cavities;
- (c) a filler ring fitted on said sleeve and disposed between the opposed ends of said casings;
- and
- (d) means for coupling said outer tubular sections.
An insulated casing assembly comprising:
- (a) a pair of coaxially arranged casings, each casing comprising radially spaced steel inner and outer tubular sections defining an annular space therebetween filled with annular layers of reflective aluminum radiation shields separated by low conductivity fiberglass spacer material enveloped in a low conductivity gas, the ends of said outer tubular section being externally threaded and having a sealable filling point communicating with said annular space for enabling evacuation of said annular space of air and back-filling thereof with said low conductivity gas;
- (b) metal fluid-tight tubular bellows at both ends of said casings, each said bellows welded at one of its ends to a first weld ring welded to the inner surface of one of said outer tubular sections, said bellows welded at its other end to a second weld ring welded to the outer surface of said inner tubular section at a location axially displaced from the end of said inner tubular section thereby forming an axially extending cavity around each said inner tubular section;
- (c) a steel sleeve tightly fitting over the opposed ends of the inner tubular sections and extending into said axially extending cavities;
- (d) a thermally insulative filler ring fitted on said sleeve and disposed between the opposed ends of said casings;
- and
- (e) a thread coupling for coupling said outer tubular sections, said thread coupling having a fluorocarbon O-ring seal on its threads.
An insulated well casing comprising radially spaced inner and outer tubular sections defining an annular space therebetween, said annular space being filled with multilayered insulation enveloped in a low conductivity gas, and a fluid-tight tubular bellows at each end of said casing, said bellows being sealed at one of its ends to the inner surface of said outer tubular section and extending axially to be sealed at its other end to the outer surface of said inner tubular section at a location axially displaced from the end of said inner tubular section thereby forming an axially extending cavity around each end of said inner tubular section.
Dependencies are inferred from the claim text.