Patent ID: 8490706
Filing Date: 2013-07-23
Classification: E21B,Y10T

Abstract:
1. A wellhead connection for connecting and sealing to a casing, the casing having an outer wall, an upper portion and an upper end, the wellhead connection comprising: a generally tubular, pressure-containing upper head housing having a top connector adapted to connect to wellhead equipment located there above, a bottom flange connector formed with a plurality of vertical ports, an inner bore adapted to accommodate the upper portion of the casing, and the inner bore having a seal profile section; a seal adapted to seal the seal profile section of the inner bore to the outer surface of the casing when the upper head housing is lowered over the casing; an annular slip bowl housing adapted to be positioned around the upper portion of the casing for connection below the upper head housing, the slip bowl housing having an upper surface, and the slip bowl housing being formed with a plurality of vertical apertures adapted to be aligned with the vertical ports of the bottom flange connector of the upper head housing; a plurality of threaded connectors adapted to extend through the vertical ports in the bottom flange connector of the upper head housing and into the vertical ports in the slip bowl housing; a plurality of slip segments adapted to be positioned within the slip bowl housing around the casing for gripping the outer wall of the casing when mechanically engaged in the slip bowl housing on connecting the upper head housing and the slip bowl housing with the threaded connectors, each of the plurality of slip segments being formed with an upper flange connector having a lower surface; and one or both of: a plurality of first compression springs, each of the plurality of compression springs being adapted to be positioned generally vertically between the upper surface of the slip bowl housing and the lower surface of the upper flange connector of each of the plurality of slip segments to maintain the plurality of slip segments vertically spaced apart from the slip bowl housing before the threaded connectors are tightened, and to compress when the slip bowl housing and the upper head housing are connected by tightening the threaded connectors so as to allow the plurality of slip segments to move radially inwardly to grip the casing; and a plurality of second compression springs, each of the plurality of compression springs being adapted to be positioned generally horizontally between adjacent of the plurality of slip segments to maintain the plurality of slip segments radially apart from each other and radially spaced from the casing before the threaded connectors are tightened, and to compress when the slip bowl housing and the upper head housing are connected by tightening the threaded connectors so as to allow the plurality of slip segments to move radially inwardly to grip the casing; such that, on connecting the slip bowl housing and the upper head housing with the threaded connectors tightened, the slip segments are energized into gripping engagement with the outer surface of the casing, locking the slip bowl housing and the upper head housing around the upper portion of the casing, and on disconnecting the threaded connectors the first compression springs, if present, push the slip segments apart from the slip bowl housing, and the second compression springs, if present, push the slip segments radially apart from the casing.