Wellhead assembly
First Claim
1. A wellhead assembly comprising a normally vertical housing provided with a central bore, with an inwardly projecting supporting shoulder, and with means for securing the housing to a surface casing, two or more casing hangers arranged concentrically in the central bore of the housing, the outermost casing hanger being suspended from the inwardly projecting supporting shoulder of the housing, and annular sealing means preventing fluid communication between an annular space around a casing hanger and a central bore, wherein each casing hanger except the innermost one is provided with an inwardly projecting supporting shoulder from which the adjacent smaller casing hanger is suspended, wherein the uppermost end of a smaller casing hanger extends further in the central bore than the uppermost end of a larger casing hanger, wherein the outer diameter of the uppermost end of a smaller casing hanger is smaller than the inner diameter of the uppermost end of a larger casing hanger, and wherein the annular sealing means are arranged between the upper end of each casing hanger and the wall of the central bore.
1 Assignment
0 Petitions
Accused Products
Abstract
A wellhead assembly comprising housing (1), an outer casing hanger (20) and at least one inner casing hanger (22,24) for suspending casings concentrically into a well. Each casing hanger (20,22,24) is provided with an external supporting shoulder (26,40,60), the external supporting shoulder (26) of said outer casing hanger (20) being supported by an internal shoulder (11) formed on the central bore (9) of the housing (1), the external supporting shoulder (40,60) of each inner casing hanger (22,24) being supported by an internal shoulder (28,42) formed on the inner surface of a surrounding casing hanger. Annular space (32,46,64) formed around the upper end of each casing hanger (20,22,24) are sealed with a metal-to-metal seal (76, 78, 79) or with an annular central member (104).
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Citations
19 Claims
- 1. A wellhead assembly comprising a normally vertical housing provided with a central bore, with an inwardly projecting supporting shoulder, and with means for securing the housing to a surface casing, two or more casing hangers arranged concentrically in the central bore of the housing, the outermost casing hanger being suspended from the inwardly projecting supporting shoulder of the housing, and annular sealing means preventing fluid communication between an annular space around a casing hanger and a central bore, wherein each casing hanger except the innermost one is provided with an inwardly projecting supporting shoulder from which the adjacent smaller casing hanger is suspended, wherein the uppermost end of a smaller casing hanger extends further in the central bore than the uppermost end of a larger casing hanger, wherein the outer diameter of the uppermost end of a smaller casing hanger is smaller than the inner diameter of the uppermost end of a larger casing hanger, and wherein the annular sealing means are arranged between the upper end of each casing hanger and the wall of the central bore.
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10. A wellhead assembly comprising:
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a normally vertical housing having a central bore, an inwardly projecting supporting shoulder, and means for securing the housing to a surface casing; two or more casing hangers arranged concentrically in the central bore of the housing, the outermost casing hanger being suspended from the inwardly projecting supporting shoulder of the housing, each casing hanger except the innermost one having an inwardly projecting supporting shoulder from which the adjacent next smaller casing hanger is suspended, the uppermost end of the smaller casing hanger extends further in the central bore than the uppermost end of a larger casing hanger, and the outer diameter of the uppermost end of the smaller casing hanger is smaller than the inner diameter of the uppermost end of the larger casing hanger; and annular sealing means between the upper end of each casing hanger and the wall of the central bore for preventing fluid communication between an annular space around a casing hanger and the central bore. - View Dependent Claims (11, 12, 13, 14, 15, 16, 17, 18)
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19. A wellhead assembly comprising:
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a normally vertical housing, comprising; a tubular lower part defining a central bore; an inwardly projecting supporting shoulder in the tubular lower portion; a tubular upper part extending the central bore, said tubular upper part being detachably connected to the tubular lower part; means for securing the housing to a surface casing; and a plurality of casing hangers arranged concentrically in the central bore of the housing, the outermost casing hanger being suspended from the inwardly projected supporting shoulder, and the outermost casing hanger and each succeeding casing hanger to the innermost, comprising; an inwardly projecting supporting shoulder from which the adjacent next smaller casing hanger is suspended in a manner such that the uppermost end of the smaller casing hanger extends further in the central bore than the uppermost end of a larger casing hanger and the outer diameter of the uppermost end of the smaller casing hanger is smaller than the inner diameter of the uppermost end of the larger casing hanger; and an outwardly projecting shoulder cooperating with the inwardly projecting supporting shoulder.
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Specification