Subsea wellhead stabilization using cylindrical sockets

A wellhead assembly comprising:

• vertical axis;
• a low pressure housing for mounting in a sea floor;
• a high pressure housing landed in the low pressure housing and having upper and lower radially thinner portions and a radially thicker portion disposed between and adjacent to the upper and lower radially thinner portions;
• a high pressure housing upper loading surface on an outer surface of the radially thicker portion that terminates at a location where the radially thicker portion transitions into the upper radially thinner portion;
• a low pressure housing upper loading surface on an inner surface of the low pressure housing and in loading contact with the high pressure housing upper loading surface to define an upper loading interface;
• a high pressure housing lower loading surface on the outer surface of the radially thicker portion that terminates at a location where the radially thicker portion transitions into the lower radially thinner portion;
• a low pressure housing lower loading surfaces on an inner surface of the low pressure housing that is in loading contact with the high pressure housing lower loading surface to define a lower loading interface;
• a port extending through a side wall of the low pressure housing between the upper and lower loading interfaces;
• an annular, concentric channel formed on the radially thicker portion of the high pressure housing between the upper and lower loading interfaces and in registry with the port;
• the lower radially thinner portion of the high pressure housing being spaced radially inward from a lower portion of the lower pressure housing, defining a casing annulus;
• and
• a passage formed in the radially thicker portion, the passage having a lower end at a lower end of the radial thicker portion in fluid communication with the casing annulus and an upper end at the channel in fluid communication with the port, the passage being radially inward and separated from the lower loading interface.

A wellhead assembly having a longitudinal axis and comprising:

• a low pressure housing having a bore;
• an upper bore socket formed in the bore at an upper end of the bore;
• a latch profile in the bore below the upper bore socket;
• a conical load shoulder formed in the bore below the latch profile;
• a lower bore socket formed in the bore below the load shoulder;
• a port extending through a side wall of the lower pressure housing at a point axially between the load shoulder and the bore lower bore socket;
• a high pressure housing landed in the bore of the low pressure housing;
• an upper external socket on the high pressure housing that engages the upper bore socket;
• a lower external socket on the high pressure housing that engages the lower bore socket;
• a latch carried by the high pressure housing below the upper external socket that snaps into engagement with the latch profile in the low pressure wellhead housing;
• a conical external load shoulder on the high pressure housing below the latch that lands on the load shoulder in the bore;
• the high pressure housing having a lower end portion extending downward from the lower external socket, defining a casing annulus between the lower end portion and the low pressure housing;
• a concentric annular channel formed in an outer surface of the high pressure housing axially between the external load shoulder and the lower external socket, radially inward from and in fluid communication with the port;
• and
• an axially extending passage having an upper end at the annular channel in fluid communication with the port and a lower end below the lower external socket in fluid communication with the casing annulus, the axially extending passage being located radially inward from the lower external socket.