Ram Style Tensioner With Fixed Conductor and Floating Frame
AssigneeVetco Gray Inc.
InventorsJoseph W. Pallini, Edward A. Mendoza
Life of this patent
Estimating the term…
Abstract
A riser tensioner for an offshore floating platform has a frame stationarily mounted to the upper portion of the riser. Pistons and cylinders are spaced circumferentially around the riser and connected between the frame and the floating platform. A tubular guide member is mounted to the floating platform for movement in unison in response to waves and currents. The riser extends through the guide member. A guide roller support is mounted to and extends downward from the frame around the guide member. At least one set of guide rollers is mounted to the guide roller support in rolling engagement with the guide member as the guide member moves in unison with the platform.
Claims17
An offshore facility having a floating platform, a riser having a lower end secured to subsea equipment and an upper portion at the platform, an improved riser tensioner, comprising:
- a frame stationarily mounted to the upper portion of the riser;
- a plurality of pistons and cylinders, each piston and cylinder being mounted between the frame and the floating platform, the cylinders being supplied with a pressurized fluid to apply tension to the riser;
- a guide member mounted to the floating platform for movement in unison in response to waves and currents;
- and
- at least one bearing carried stationarily by the frame and in movable engagement with the guide member as the guide member moves in unison with the platform.
An offshore facility, having a floating platform, a riser having a lower end secured to subsea equipment and an upper portion extending through an opening in the platform, an improved riser tensioner, comprising:
- a frame stationarily mounted to the upper portion of the riser;
- a plurality of pistons and cylinders spaced circumferentially around the opening, each piston and cylinder being mounted between the frame and the floating platform, the cylinders being supplied with a pressurized fluid to apply tension to the riser;
- a tubular guide member mounted to the floating platform for movement in unison in response to waves and currents, the riser extending through the guide member;
- a guide roller support stationarily mounted to and extending downward from the frame around the guide member;
- and
- at least one set of guide rollers mounted to the guide roller support, spaced circumferentially around the guide member and in rolling engagement with the guide member as the guide member moves in unison with the platform.
A method of tensioning a riser extending from subsea equipment to a floating platform, which includes mounting a frame to the riser, and mounting pistons and cylinders between the platform and the frame, and supplying the cylinders with fluid pressure to apply tension to the riser, the improvement comprising:
- (a) mounting a guide member to the platform;
- (b) mounting a guide roller support to the frame, and mounting a set of guide rollers to the guide roller support and in rolling engagement with the guide member;
- and
- (c) in response to platform movement toward and away from the subsea equipment due to waves and/or current, moving the guide member in unison with the platform and relative to the guide roller support and set of guide rollers, which remain stationary with the riser.
Dependencies are inferred from the claim text.