Adjustable riser suspension and sealing system

摘要

An adjustable riser suspension system for suspending a riser under tension including a riser hanger, a mating sleeve rotationally coupled to the riser hanger, a ratchet-latch sleeve located inside the mating sleeve with an external profile configured to engage an internal profile of the mating sleeve and an internal profile configured to engage an externally threaded face of the riser. The riser hanger and mating sleeve are configured to move downward relative to the riser such that the mating sleeve fits over at least a portion of the riser, causing the ratchet-latch device to ratchet over the external threads of the riser. The mating sleeve is configured to rotate relative to the riser, causing the internal and external profiles of ratchet-latch device to lock the riser and the mating sleeve to prevent movement of the riser relative to the mating sleeve.

主权项

1. A running tool configured to manipulate an adjustable riser suspension system to suspend a riser under tension, comprising:
a work string configured to detachably couple to the riser; a piston affixed to the work string; an expansion cylinder disposed about the piston, wherein the expansion cylinder is configured to communicate with a riser hanger coupled to a mating sleeve; an annular element affixed to the work string, wherein the annular element comprises a hydraulic conduit; hydraulic sleeves disposed about the upper and lower portions of the annular element that define hydraulic chambers, wherein the hydraulic chambers are coupled by the hydraulic conduit and wherein each of the hydraulic sleeves further comprises a guide pin on its exterior surface; and a rotating sleeve disposed about the annular element and having a helical groove on its interior surface, wherein the helical groove is engaged by the guide pins on the exterior surfaces of the hydraulic sleeves such that axial expansion of the hydraulic sleeves rotates the rotating sleeve.