Downhole riser assembly

Details Downhole riser assembly Downhole riser assembly

1979-02-21

1980-12-23

Pate, III, William F.

Wells

Submerged well

Riser

175 7, 405195, E21B 1701

Patent

active

042405068

ABSTRACT:
A downhole riser assembly includes a tubular casing embedded in the ocean floor, said casing having a constant internal diameter and an upper end extending above said ocean floor. A tubular riser pipe is disposed in the casing and has an upper end connected to a floating vessel which may be a tension leg platform. The casing and riser are rigidly connected at a considerable distance below the ocean floor, said distance being on the order of 100 feet. When the floating structure is laterally displaced from a position directly above the casing, the riser pipe contacts the upper end of the casing. This contact limits the lateral deflection of the riser at the ocean floor and thereby limits the stresses in the riser. The distance between the upper end of the casing and the downhole connection between the casing and the riser, and the diameter of the casing are such that the riser has a rotational stiffness, adjacent the upper end of the casing, within a range such that both a maximum design maximum stress and a maximum design bottom slope of said riser are not exceeded when said riser is subjected to maximum design loading conditions. An alternative embodiment of the present invention provides a lateral support means for connecting the riser and the casing adjacent the upper end of the casing for restricting lateral movement of the riser.

REFERENCES:
patent: 3142344 (1964-07-01), Otteman et al.
patent: 3516488 (1970-06-01), Joubert et al.
patent: 4053022 (1977-10-01), Mercier
patent: 4126183 (1978-11-01), Walker

Affiliated with

Also associated with

Rating

Downhole riser assembly does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Downhole riser assembly, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Downhole riser assembly will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2237948