Wellhead completion system

In a well having a wellhead housing having a bore with a cylindrical bore wall, an annular groove formed in the bore wall which defines an upward facing load shoulder having an inner diameter that is flush with an inner diameter of the bore wall, a tubular member extending coaxially within the bore and having a cylindrical exterior tubular member wall spaced inward from the bore wall, an improved apparatus for sealing between the tubular member wall and the bore wall, comprising in combination:

• a metal seal having inner and outer cylindrical walls separated by an annular cavity and joined at a lower end by a base;
• a cam member fixed on the base of the seal, having a downward and outward facing cam shoulder;
• a split load ring;
• means for retaining the load ring on the cam member in a contracted position while the seal is lowered around the tubular member, and for releasing the load ring to move outward into the groove when the load ring contacts structure located in the bore below the load shoulder, the cam shoulder then pushing the load ring into the groove to lock the seal to the wellhead housing;
• and
• an energizing ring carried by the seal and movable between an upper position and a lower position, for moving downward in the cavity for deforming the seal into engagement with the bore wall and tubular member wall.

In a well having a wellhead housing having a bore with a cylindrical bore wall, an annular lower groove formed in the bore wall which defines an upward facing load shoulder having an inner diameter that is flush with an inner diameter of the bore wall, an annular upper groove located above the lower groove, a section of casing extending coaxially within the bore, the casing having a cut upper end within the bore, an improved apparatus for supporting the casing and sealing between the casing and the bore wall, comprising in combination:

• a set of slips positioned in the bore below the load shoulder and in engagement with the casing for supporting the casing in the wellhead housing;
• a metal seal having inner and outer cylindrical walls separated by an annular cavity and joined at a lower end by a base;
• a cam member fixed on the base of the seal, having a downward and outward facing cam shoulder;
• a split load ring;
• shear pin means for retaining the load ring on the cam member in a contracted position while the seal is lowered around the tubular member, and for releasing the load ring to move outward into the lower groove when the load ring contacts an upper end of the slips, the cam shoulder then pushing the load ring into engagement with the load shoulder to lock the seal to the wellhead housing;
• an energizing ring carried by the seal and movable between an upper position and a lower position, for moving downward in the cavity for deforming the seal into engagement with the bore wall and the tubular member wall;
• and
• energizing ring locking means in engagement with the energizing ring and the upper groove for locking the energizing ring to the wellhead housing while in the lower position.

In a well having a wellhead housing having a bore with a cylindrical bore wall, an annular groove located within the bore, a section of casing extending coaxially within the bore, the casing having a cut upper end within the bore, and a seal located between the casing and the bore wall, an improved locking apparatus for locking the seal and the casing to the wellhead housing, comprising in combination:

• inner and outer sleeves which threadingly engage each other to allow axial movement of the sleeves relative to each other;
• one of the sleeves having a cam surface;
• a locking element carried by the sleeves in engagement with the cam surface for movement from an inner position to an outer position in engagement with the groove when the sleeves are rotated relative to each other, and with one of the sleeves bearing against an upper end of the seal to prevent upward movement of the seal;
• and
• a casing lock ring that has mating threads for engaging one of the sleeves and an inward extending flange that engages the upper end of the casing to prevent upward movement of the casing due to temperature increase.