Abstract: A pressure mitigating device is used to reduce pressure in a void within a wellhead housing. In one embodiment, the pressure mitigating device includes two plates that define a void between them. Increased pressure in the wellhead housing causes the plates to elastically displace towards each other. The plates contact each other, limiting the displacement prior to plastic deformation.

Abstract: A pressure relief device is used to relieve pressure in a void within a wellhead housing. In one embodiment, the pressure relief device includes a plunger having a stepped plug, wherein the plug can be fully open to allow flow from the void, restricted to allow a predetermined flow to relieve pressure, or closed to prevent flow from the void. In another embodiment, the pressure relief device includes a vacuum puller that creates negative pressure in a vessel. As fluid in the void expands, it is able to enter the space formerly occupied by the plunger. In yet another embodiment, a rupture disc is used to prevent fluid from flowing from the void, through a passage, to the wellbore. If pressure in the void exceeds a predetermined value, the rupture disc yields and allows the trapped fluid to flow to the wellbore.

Abstract: A pressure relief device is used to relieve pressure in a void within a wellhead housing. In one embodiment, the pressure relief device includes a plunger having a stepped plug, wherein the plug can be fully open to allow flow from the void, restricted to allow a predetermined flow to relieve pressure, or closed to prevent flow from the void. In another embodiment, the pressure relief device includes a vacuum puller that creates negative pressure in a vessel. As fluid in the void expands, it is able to enter the space formerly occupied by the plunger. In yet another embodiment, a rupture disc is used to prevent fluid from flowing from the void, through a passage, to the wellbore. If pressure in the void exceeds a predetermined value, the rupture disc yields and allows the trapped fluid to flow to the wellbore.

Abstract: A pressure mitigating device is used to reduce pressure in a void within a wellhead housing. In one embodiment, the pressure mitigating device includes two plates that define a void between them. Increased pressure in the wellhead housing causes the plates to elastically displace towards each other. The plates contact each other, limiting the displacement prior to plastic deformation.

Abstract: A pressure relief device is used to relieve pressure in a void within a wellhead housing. In one embodiment, the pressure relief device includes a plunger having a stepped plug, wherein the plug can be fully open to allow flow from the void, restricted to allow a predetermined flow to relieve pressure, or closed to prevent flow from the void. In another embodiment, the pressure relief device includes a vacuum puller that creates negative pressure in a vessel. As fluid in the void expands, it is able to enter the space formerly occupied by the plunger. In yet another embodiment, a rupture disc is used to prevent fluid from flowing from the void, through a passage, to the wellbore. If pressure in the void exceeds a predetermined value, the rupture disc yields and allows the trapped fluid to flow to the wellbore.

Abstract: A pressure relief device is used to relieve pressure in a void within a wellhead housing. In one embodiment, the pressure relief device includes a plunger having a stepped plug, wherein the plug can be fully open to allow flow from the void, restricted to allow a predetermined flow to relieve pressure, or closed to prevent flow from the void. In another embodiment, the pressure relief device includes a vacuum puller that creates negative pressure in a vessel. As fluid in the void expands, it is able to enter the space formerly occupied by the plunger. In yet another embodiment, a rupture disc is used to prevent fluid from flowing from the void, through a passage, to the wellbore. If pressure in the void exceeds a predetermined value, the rupture disc yields and allows the trapped fluid to flow to the wellbore.

Abstract: A subsea wellhead assembly includes a wellhead housing, a production tree, a tubing hanger adapted to land in the wellhead assembly inside the wellhead housing without a need for angular orientation, a bridge member on the tubing hanger in the production tree, a port radially formed through the tubing hanger or the bridge member, a production port radially through the tree head housing, and an annular production flow passage that circumscribes the bridge member lower portion on one end and optionally circumscribes the tubing hanger on its other end. The annular production flow passage is in communication with both the production port and the radial port in the tubing hanger or bridge member so that fluid can be produced from the well via the annular production flow passage without necessity to orientate the tubing hanger.

Abstract: A subsea wellhead assembly includes a wellhead housing, a production tree, a tubing hanger adapted to land in the wellhead assembly inside the wellhead housing without a need for angular orientation, a bridge member on the tubing hanger in the production tree, a port radially formed through the tubing hanger or the bridge member, a production port radially through the tree head housing, and an annular production flow passage that circumscribes the bridge member lower portion on one end and optionally circumscribes the tubing hanger on its other end. The annular production flow passage is in communication with both the production port and the radial port in the tubing hanger or bridge member so that fluid can be produced from the well via the annular production flow passage without necessity to orientate the tubing hanger.