Patent ID: 7798231
Filing Date: 2010-09-21
Classification: E21B

Abstract:
1. A subsea wellhead assembly for a subsea well, comprising: a low pressure wellhead housing having a string of conductor piping extending therefrom; a high pressure wellhead housing adapted to have a string of outer casing suspended therefrom and to land within the low pressure wellhead housing, the high pressure wellhead housing having a housing bore; an adapter adapted to be positioned within the housing bore, the adapter having an external load shoulder adapted to land on a housing load shoulder of the high pressure wellhead housing and an adapter bore with an adapter load shoulder formed thereon; a first casing hanger adapted to be carried in the adapter bore and to have a string of inner casing suspended therefrom, the first casing hanger being adapted to land on the adapter load shoulder; a second casing hanger adapted to be carried in the adapter bore and to have a string of inner casing suspended therefrom, the second casing hanger being adapted to land on the first casing hanger; a first metal seal assembly adapted to be disposed between the first casing hanger and the adapter to seal an annulus therebetween; and a second metal seal assembly adapted to be disposed between the second casing hanger and the adapter to seal an annulus therebetween.