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Title: Subsea pipeline gets welded branch without halting flow

Abstract

In October 1994, a 16 in. welded branch was installed without interruption to production onto Wintershall Noordzee BV`s 36-in. gas pipeline from the K13-A platform in the Dutch sector of the North Sea to Den helder, The Netherlands. The procedure is the first successfully to combine hyperbaric welding and subsea hot tapping without interruption to production. Developers of new fields can now consider exporting product without interrupting existing production and through existing infrastructure even if no convenient tie-in locations exist. Unocal evaluated export options and established that the most attractive alternative was to export gas into the Wintershall 36-in. K13-A to Den Helder pipeline. Various options for installing a branch included the following: flooding the pipeline and installing a conventional tee; stopping production and installing a welded branch followed by hot tapping; and continuing production and installing a welded branch followed by hot tapping. The chosen scheme was to retrofit a subsea side-tap assembly. This was achieved by installation of a welded branch followed by hot tapping into the 36-in. pipeline. The paper describes location determination, schedules, onshore preparation, and offshore work.

Authors:
;  [1];  [2]
  1. Stolt Comex Seaway Ltd., Aberdeen (United Kingdom)
  2. Wintershall Noordzee B.V., Den Helder (Netherlands)
Publication Date:
OSTI Identifier:
136995
Resource Type:
Journal Article
Journal Name:
Oil and Gas Journal
Additional Journal Information:
Journal Volume: 93; Journal Issue: 50; Other Information: PBD: 11 Dec 1995
Country of Publication:
United States
Language:
English
Subject:
03 NATURAL GAS; NORTH SEA; PIPELINES; NETHERLANDS; MODIFICATIONS; WELDED JOINTS; PIPE JOINTS; NATURAL GAS; TRANSPORT; SUPPLY DISRUPTION; MITIGATION; RETROFITTING; DESIGN

Citation Formats

West, A, Hutt, G, and Starsmore, R. Subsea pipeline gets welded branch without halting flow. United States: N. p., 1995. Web.
West, A, Hutt, G, & Starsmore, R. Subsea pipeline gets welded branch without halting flow. United States.
West, A, Hutt, G, and Starsmore, R. 1995. "Subsea pipeline gets welded branch without halting flow". United States.
@article{osti_136995,
title = {Subsea pipeline gets welded branch without halting flow},
author = {West, A and Hutt, G and Starsmore, R},
abstractNote = {In October 1994, a 16 in. welded branch was installed without interruption to production onto Wintershall Noordzee BV`s 36-in. gas pipeline from the K13-A platform in the Dutch sector of the North Sea to Den helder, The Netherlands. The procedure is the first successfully to combine hyperbaric welding and subsea hot tapping without interruption to production. Developers of new fields can now consider exporting product without interrupting existing production and through existing infrastructure even if no convenient tie-in locations exist. Unocal evaluated export options and established that the most attractive alternative was to export gas into the Wintershall 36-in. K13-A to Den Helder pipeline. Various options for installing a branch included the following: flooding the pipeline and installing a conventional tee; stopping production and installing a welded branch followed by hot tapping; and continuing production and installing a welded branch followed by hot tapping. The chosen scheme was to retrofit a subsea side-tap assembly. This was achieved by installation of a welded branch followed by hot tapping into the 36-in. pipeline. The paper describes location determination, schedules, onshore preparation, and offshore work.},
doi = {},
url = {https://www.osti.gov/biblio/136995}, journal = {Oil and Gas Journal},
number = 50,
volume = 93,
place = {United States},
year = {Mon Dec 11 00:00:00 EST 1995},
month = {Mon Dec 11 00:00:00 EST 1995}
}