Dril-quip, Inc.

Steven M Hafernik

Fife Baker Ellis

Neil B Prasad

Systems and methods for pressure communication within a hydro-pneumatic cylinder are provided. The hydro-pneumatic cylinder generally includes a rod, a barrel coaxial to the rod, and a piston assembly disposed within the barrel and connected to the rod. The barrel is hollow to define a chamber, and the piston assembly is axially movable within the chamber to stroke the rod relative to the barrel. The hydro-pneumatic cylinder includes: a flow path formed axially through the rod of the cylinder. This flow path may allow for pressure communication between a low-pressure side of the cylinder and a pressure energized lower pin located at a distal end of the rod. The lower pin may be actuated, via this pressure communication to secure the end of the cylinder to a tension ring on a riser.

Hydro-pneumatic cylinder with annulus fluid bypass

In accordance with embodiments of the present disclosure, a ram-style riser tensioner system includes a plurality of cylinders for applying a desired tension to a riser, a support structure coupled to the riser, and a plurality of gas accumulators. Each of the cylinders is coupled to the support structure, and each of the gas accumulators is configured to provide pressurized gas to a corresponding one of the cylinders. The ram-style riser tensioner also includes a plurality of support rods coupled to the support structure for reducing bending moments on the plurality of cylinders.

Enhanced ram-style riser tensioner

In accordance with embodiments of the present disclosure, a ram-style riser tensioner cylinder assembly includes an outer cylinder barrel and an inner rod barrel disposed within and extending in a first direction from the outer cylinder barrel. The cylinder assembly also includes a high pressure seal disposed along a sliding interface between an end of the inner rod barrel and an inner wall of the outer cylinder barrel. In addition, the cylinder assembly includes a cap coupled to an end of the inner rod barrel extending from the outer cylinder barrel, and a fluid reservoir disposed in the cap. The fluid reservoir may be used to store and communicate fluid from the fluid reservoir to the high pressure seal for lubricating the seal.

Enhanced ram-style riser tensioner cylinder

An example deflection absorbing tensioner frame for a platform of an offshore vessel may include at least one metal beam supporting a tensioner. A deflection absorber may be coupled to at least one metal beam. The deflection absorber may be configured to absorb axial, rotational, and lateral deflections in a platform deck coupled to the deflection absorber.

Deflection absorbing tensioner frame

Improved methods and systems for connecting a riser tensioner system to a riser are disclosed. A system for coupling a tensioner cylinder to a riser includes a top pin connection disposed at a first distal end of the tensioner cylinder. The top pin connection couples the tensioner cylinder to a platform. The tensioner cylinder includes an extension rod and a bottom pin connection is disposed at a second distal end of the tensioner cylinder on the extension rod. A tension ring is coupled to the riser. An adjustable linkage system is coupled to the tensioner cylinder and includes an attachment mechanism and a positioning mechanism. The adjustable linkage system is operable to couple the tensioner cylinder to the tension ring.

Methods and systems for tensioner connection

A cylinder accumulator system is disclosed. The system includes a cylinder comprising a cylinder rod, a cylinder barrel coaxial to the cylinder rod, a cylinder end cap coupled to the cylinder barrel and the cylinder rod, and a cylinder piston assembly disposed within the cylinder barrel. The cylinder piston assembly further includes a dynamic sealing arrangement, which comprises one or more dynamic seals. The system further includes a first annular volume coaxial to the cylinder rod and the cylinder barrel, and a second volume disposed within the cylinder piston assembly. The system also includes a piston disposed within a bore of the second volume and between a hydraulic fluid located on a first side of the piston and a gas media located on a second side of the piston. The system also includes an external high-pressure accumulator, a low-pressure accumulator, and one or more tube manifolds coupling the external high-pressure accumulator and low-pressure accumulator to the cylinder.

Hydro-pneumatic tensioner with fluid retention device

The riser tensioning system () includes a tensioning ring () for secured engagement with the riser and plurality of hydraulic cylinders () extending between the tensioning ring and a floating platform. A gimbal mechanism () acts between the platform and the riser to allow the riser axis to tilt relative to the floating platform. One or more elongate torque transfer members () extend between the tensioning ring and the gimbal mechanism and allow axial movement of the tensioning ring and the riser with respect to the floating platform.

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Houston, TX, United States of America

Steven M Hafernik