Aker Solutions As

Aker Subsea Inc.

Jan Herland

Lars Timberlid Lundheim

Anders Billington

Joakim Martens

Neil Ryan

Geir Ivar Holberg

Edin Pita

Jan Troensdal

Viktor Grennberg

Kristian Guttulsrud

Alexander Paul Lazell

A wellhead arrangement includes a valve tree arranged on a wellhead and a seal carrier with at least one seal. The valve tree includes an isolation sleeve. The seal carrier is arranged between the wellhead and the isolation sleeve.

Wellhead arrangement and method

The invention relates to a gate valve assembly () for use in a subsea workover system comprising: &#x2014;a valve block () having a flow path (); &#x2014;valve seats () located within the valve block () around a periphery of the flow path (), &#x2014;a gate valve member () which is moveable across the flow path () between a first position in which the flow path () is open and a second position in which the flow path () is closed; &#x2014;said gate valve member () comprising a first portion () surrounding an opening () adapted to mate with the flow path () when the gate valve member () is in the first position, said first portion () is provided with a cutting member () arranged on the periphery of the first portion () towards the opening (). The gate valve member () further comprises a second portion () having at least one recessed part (), said recessed part () being positioned such that when the gate valve member () is in the second position, the gate valve member () and the seats () forms a sealing area () arranged on a planar surface of the gate valve member ().

Gate valve assembly for a subsea workover system

An offshore methane hydrate production assembly (), having a tubing () extending into a subsea well () that extends down to a methane hydrate formation () below the seabed (). A submersible pump () is arranged in the tubing (). A methane conduit () extends down from a surface installation (). A well control package () landed on a wellhead () is positioned at the upper end of the subsea well (). Moreover, an emergency disconnection package () is arranged between the methane conduit () and the well control package (). The tubing () is suspended from the well control package (). Other aspects of the invention are also disclosed.

Subsea methane hydrate production

The invention provides a cutting valve comprising a valve block, a gate, which is slidably within a cavity in the valve block from an open position to a closing and cutting position, an upper seat arranged in an upper part of the valve between the valve block and the gate, and a lower seat arranged in a lower part of the valve between the valve block and the gate, The valve further comprises an upper resilient member arranged between the upper seat and a lower resilient member arranged between the valve block and the lower seat. The cutting valve being distinctive in that the combination of height of upper seat, and lower seat, resilient member and any spacers on the lower side of the gate is selected so that an allowed travelling distance for the upper seat towards the valve block and an allowed travelling distance for the lower seat towards the valve block, are substantially equal.

Asymetrically cutting valve seats

A gate valve assembly () for use in subsea workover systems is disclosed. In an embodiment, the gate valve assembly () includes a valve block (). The valve block () includes a cutting gate () disposed in a valve cavity () such that the cutting gate () can engage in a reciprocating motion in the valve cavity () between an 'open' position and a 'closed' position. The reciprocating motion of the cutting gate () results in a cutting operation of a tubing conveyed string passing through the gate valve assembly (). The gate valve assembly () further includes a slug pit () formed in the valve block () alongside the valve cavity (). The slug pit () defines an opening which can contain one or more cuttings from tubing conveyed springs resulting from the cutting operation. The reciprocating motion of the cutting gate () transports one or more cuttings of the tubing conveyed string to the slug pit ().

Growing community of inventors

Nesbru, Norway

Jan Herland