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Title: Wind induced resonant cross flow vibrations on Norwegian offshore flare booms

Abstract

Vibrations and fatigue cracking have occurred, for some years, i flare boom structures on a number of platforms on the Norwegian continental shelf. In view of this, the objective of this paper is to: (1) Describe the vibrations and its characteristics on Statfjord A and Heimdal which had the largest vibrations, the vibrations can`t be predicted by vortex induced vibrations of individual members but could be caused by wake effects, local frame vibrations or global dynamic effects. (2) Review the evaluation of cracks in other flare boom structures, the work has been based on DIN 4133 and includes vibrations of both individual members and frames. (3) Review the design practice and operational experience with design parameters especially measurements of damping on individual tubular members and observed vibrations of individual members and frames. Possible limitations of the DIN standard will be discussed. (4) A promising device for reducing the vibrations is described. The problems have mainly been caused by the methods used in design, however, evidence of welding defects initiating fatigue cracks has also been found. A review of the existing methods has led to the recommendation of using the German DIN 4133 code for design purposes. This code is tomore » a large extent similar to the proposed Eurocode-1. A design procedure based on DIN 4133 is proposed including additional parametric boundaries for avoiding resonant vibration.« less

Authors:
 [1];  [2]
  1. Statoil, Stavanger (Norway)
  2. Norwegian Petroleum Directorate, Stavanger (Norway)
Publication Date:
OSTI Identifier:
194717
Report Number(s):
CONF-950695-
ISBN 0-7918-1307-X; TRN: IM9611%%219
Resource Type:
Conference
Resource Relation:
Conference: International conference on offshore mechanics and arctic engineering, Copenhagen (Denmark), 18-22 Jun 1995; Other Information: PBD: 1995; Related Information: Is Part Of OMAE 1995 -- Proceedings of the 14. international conference on offshore mechanics and arctic engineering. Volume 1, Part B: Offshore technology; Chakrabarti, S.K. [ed.] [Chicago Bridge and Iron Technical Services, Plainfield, IL (United States)]; Gudmestad, O.T. [ed.] [Statoil, Stavanger (Norway)]; Sparks, C. [ed.] [Inst. Francais du Petrole, Rueil-Malmaison (France)]; Morrison, D.G. [ed.] [Shell E and P Technology Co., Houston, TX (United States)]; PB: 539 p.
Country of Publication:
United States
Language:
English
Subject:
42 ENGINEERING NOT INCLUDED IN OTHER CATEGORIES; 02 PETROLEUM; NORWAY; OFFSHORE PLATFORMS; FATIGUE; CRACK PROPAGATION; MECHANICAL VIBRATIONS; CONTROL; GASEOUS WASTES; FLARING; SUPPORTS

Citation Formats

Oppen, A.N., and Kvitrud, A. Wind induced resonant cross flow vibrations on Norwegian offshore flare booms. United States: N. p., 1995. Web.
Oppen, A.N., & Kvitrud, A. Wind induced resonant cross flow vibrations on Norwegian offshore flare booms. United States.
Oppen, A.N., and Kvitrud, A. Sun . "Wind induced resonant cross flow vibrations on Norwegian offshore flare booms". United States. doi:.
@article{osti_194717,
title = {Wind induced resonant cross flow vibrations on Norwegian offshore flare booms},
author = {Oppen, A.N. and Kvitrud, A.},
abstractNote = {Vibrations and fatigue cracking have occurred, for some years, i flare boom structures on a number of platforms on the Norwegian continental shelf. In view of this, the objective of this paper is to: (1) Describe the vibrations and its characteristics on Statfjord A and Heimdal which had the largest vibrations, the vibrations can`t be predicted by vortex induced vibrations of individual members but could be caused by wake effects, local frame vibrations or global dynamic effects. (2) Review the evaluation of cracks in other flare boom structures, the work has been based on DIN 4133 and includes vibrations of both individual members and frames. (3) Review the design practice and operational experience with design parameters especially measurements of damping on individual tubular members and observed vibrations of individual members and frames. Possible limitations of the DIN standard will be discussed. (4) A promising device for reducing the vibrations is described. The problems have mainly been caused by the methods used in design, however, evidence of welding defects initiating fatigue cracks has also been found. A review of the existing methods has led to the recommendation of using the German DIN 4133 code for design purposes. This code is to a large extent similar to the proposed Eurocode-1. A design procedure based on DIN 4133 is proposed including additional parametric boundaries for avoiding resonant vibration.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Sun Dec 31 00:00:00 EST 1995},
month = {Sun Dec 31 00:00:00 EST 1995}
}

Conference:
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