WO1994009245A1 - Raidisseur antiflexion - Google Patents

Raidisseur antiflexion Download PDF

Info

Publication number
WO1994009245A1
WO1994009245A1 PCT/NO1993/000150 NO9300150W WO9409245A1 WO 1994009245 A1 WO1994009245 A1 WO 1994009245A1 NO 9300150 W NO9300150 W NO 9300150W WO 9409245 A1 WO9409245 A1 WO 9409245A1
Authority
WO
WIPO (PCT)
Prior art keywords
bending stiffener
flange
stiffener
bending
bore
Prior art date
Application number
PCT/NO1993/000150
Other languages
English (en)
Inventor
Bjarne Kjaer
Original Assignee
Viking-Mjøndalen A.S
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Viking-Mjøndalen A.S filed Critical Viking-Mjøndalen A.S
Priority to GB9507190A priority Critical patent/GB2286414B/en
Priority to AU52872/93A priority patent/AU5287293A/en
Publication of WO1994009245A1 publication Critical patent/WO1994009245A1/fr

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
    • F16L57/00—Protection of pipes or objects of similar shape against external or internal damage or wear
    • F16L57/02—Protection of pipes or objects of similar shape against external or internal damage or wear against cracking or buckling
    • E—FIXED CONSTRUCTIONS
    • E21—EARTH OR ROCK DRILLING; MINING
    • E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B17/00—Drilling rods or pipes; Flexible drill strings; Kellies; Drill collars; Sucker rods; Cables; Casings; Tubings
    • E21B17/01—Risers
    • E21B17/017—Bend restrictors for limiting stress on risers
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
    • F16L35/00—Special arrangements used in connection with end fittings of hoses, e.g. safety or protecting devices
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02G—INSTALLATION OF ELECTRIC CABLES OR LINES, OR OF COMBINED OPTICAL AND ELECTRIC CABLES OR LINES
    • H02G15/00—Cable fittings
    • H02G15/007—Devices for relieving mechanical stress
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02G—INSTALLATION OF ELECTRIC CABLES OR LINES, OR OF COMBINED OPTICAL AND ELECTRIC CABLES OR LINES
    • H02G3/00—Installations of electric cables or lines or protective tubing therefor in or on buildings, equivalent structures or vehicles
    • H02G3/22—Installations of cables or lines through walls, floors or ceilings, e.g. into buildings

Definitions

  • the present invention relates to a bending restricting device (hereinafter referred to as a bending stiffener) , which is used where cables, flexible risers, umbilicals, etc. are guided into a receiving station, for example an offshore plat ⁇ form.
  • the bending stiffener consists of an elastic composite, reinforced structure, having an internal axial bore and a flange for mounting the bending stiffener to the receiving station.
  • the present invention relates to said flange and fastening of the axial reinforcement of the bending stiffener to the flange.
  • bending stiffeners of the above type are used in situations where requirements to the bending radius of the cables etc. exist, or where it in general is desirable to protect cables going into a receiving station.
  • the invented bending stiffener may for example be used when guiding flexible risers into the floating construction of a tension leg platform.
  • Bending stiffeners of the present type are specially known in the offshore industry, and such bending stiffeners traditionally are made of a solid steel flange with welded on axial reinforcement toward the flexible part of the bending stiffener.
  • connection between the flange and the axial reinforcement is very important for the properties of the bending stiffener for example in relation to the desired stiffness and design life (fatigue) .
  • fatigue has in some cases resulted in that bending stiffeners of traditional construction have collapsed.
  • the bending stiffener of the present invention provides a better distribution of the forces and thereby a significantly increased fatigue strength in relation to the traditional solutions. According to the invention this is achieved by a bending stiffener designed for mounting to a receiving station, preferably an offshore platform, for guiding cables, flexible risers, umbilicals etc.
  • the bending stiffener which comprises a termination end arranged to the receiving station, a circular flange including an inner bore, where it to and internal to this is provided a cylindrical insert with an internal bore diameter equal to the bore diameter of the bending stiffener, a composition of a rubber compound with an internal bore, and outer dimensions equal to the bending stiffener is fastened to the end flange/insert and is formed in the longitudinal direction with a substantially conical outer taper toward the flexible end/- cable inlet end of the flexible stiffener.
  • the composition further including layers of axial reinforcement, connected with crossing cord layers therebetween and reinforcement and an outer protection layer wrapped around the outer periphery of the bending stiffener.
  • the bending stiffener device is characterized in that the flange is formed with a number of radial openings (windows) distributed around the flange, and the axial reinforcement runs from the flexible portion of the bending stiffener toward and through a radial opening in the flange and back toward the flexible portion of the bending stiffener through another radial opening in the flange.
  • Fig. 1 shows a sectional side view of the bending stiffener according to the invention
  • Fig. 2 shows a cross section of the end flange of the bending stiffener of Fig. 1.
  • the construction (bending stiffener) 1 is based on an elastic composite construction terminated at a steel flange 2.
  • the elastic compound consists of an assembly of reinforcement cords 8, 9 and rubber matrix 7.
  • the properties of such compounds are dependent on lay angle and fibers, fraction fill, thickness of rubber between fiber layers, loading direction and material properties.
  • the chosen materials are within the production and manufacturing range of the company of the inventor. Extensive engineering has been carried out in order to develope a suitable design based on the materials available. Detailed analyses of the bending stiffener 1 has been performed by using FEM-techniques.
  • the bending stiffener 1 has an internal axial bore 6 and is designed for a flexible gas-injection riser with an inner diameter of 203,2 mm (8") and 414 bar internal pressure.
  • the bending stiffener 1 is further designed for a design life of 20 years, and adapted to operate in an offshore environment in air, splash zone, and in submerged state.
  • the design of the bending stiffener 1 is an optimal combination of material and manufacturing technology using elastic composites and advanced calculation techniques.
  • the bending stiffener 1 is an elastic composite construction consisting of the following elements: steel end flange 2, axial aramide reinforcement 8, circumferential aramide reinforcement 11, cross-laid steel cord 9, natural rubber compound 7, rayon pearls 10, and outer layer of neophrene 12.
  • the bending stiffener 1 is shown in Fig. 1.
  • the end flange 2 is bolted at 5 to the flexible pipe termination 14.
  • the bending stiffener 1 is fixed to the end flange 2 by three mechanisms: 1) the rubber 7 is bonded to the steel 2,
  • the axial aramide reinforcement 8 is made by strips running from the flexible end 13 of the stiffener 1, through a radial opening 3 in the flange 2 and back into the stiffener 1 through another radial opening 3.
  • the area between the radial openings 3 is machined to a cylindrical shape to avoid stress concentrations.
  • the cylinder diameter is more than 20 fiber- rope diameters. (20 rope diameters is used for obtaining full strength efficiency of aramide ropes 8) , and
  • a cylindrical steel insert 4 with a bulb at the outer end is used internally.
  • This insert stiffener 4 is the innermost part of the construction 1 and provides additional anchoring of the stiffener 1 to the end flange 2.
  • the axial aramide reinforcement 8 is the main mechanism for terminating the forces.
  • the axial aramide reinforcement 8 gives sigificant contribution to the bending stiffness of the construction 1.
  • the circumferential aramide reinforcement 11 is wrapped on the outside of the stiffener 1. This is done to ensure that the compression side of the stiffener 1 can take the compressive stresses. With this circumferential reinforcement 11 the radial expansion is restricted at the compression side. The compression will hence results in pressure build-up in the rubber 7. This pressure will be a major part of the compression stiffness of the stiffener 1.
  • the matrix selected is a natural rubber compound 7 due to the excellent bonding to the steel 2, 4, the excellent fatigue properties and that the material 7 is well suited for manufacturing of such devices.
  • a clorophrene outer layer 12 is used to provide UV- and ozon-resistance of the stiffener 1. The design analysis has been performed using the Finite Element Program NISA.
  • the bending stiffener 1 is built up in layers with natural rubber 7 and cord 8 on a steel mandrel with flanges that can be fastened in each end.
  • the termination flange 7 is fastened in one end of the mandrel.
  • Layers of rubber 7 are built on the mandrel.
  • the aramide sheet (Kevlar) 8 is laid through the windows 3 of the termination flange 2, rolled flat and adhered to the rubber 7 in the specified length. Between the aramide sheets 8 corresponding rubber subjects 7 will be filled up.
  • Two cross-laid layers of steel cord 9 are added at 37,5° angle with the aramide 8.
  • Rubber 7 is laid until the diameter match the next aramide layer 8.
  • the free ends of aramide layer one 8 are drawn through window 3 circle two, rolled out and then fastened. The operation is repeated until all the required axial aramide 8 and steel cord layers 9 are built in.
  • One layer of circum- ferential aramide 11 is wrapped around the stiffener 1 to provide hoop strength of the stiffener l.
  • a rubber layer of neophrene 12 is placed over the stiffener 1 and the terminating flange 2.
  • Neophrene 12 is applied on the back side of the flange 2 to protect the aramide. To ensure metal-to-metal contact in the bolting circle 5 the back side of the flange 2 is machined down in the area where rubber is applied.
  • the results of the FEM-analysis were compared with a full scale test, and the two test results were in good agreement to each other.
  • the base case for the design 1 has been a 203,2 mm (8") with 414 bars gas riser used on a production vessel in 300 m water depth. This corresponds to a top tension load of 700 kN and 30° angle with a radius of curvature of 3,1 m in the bending stiffener 1.
  • the weight of the bending stiffener 1 is about 1500 kg, the axial length is 1,8 m and the diameter at the end flange is 1,2 m.
  • the analysis has verified that the bending stiffener design 1 can meet the specified loads and the utilization of different components are below the acceptable values.
  • the termination of the elastic composite to the steel flange 2 is achieved by mechanical termination of the reinforcing members 8 in a manner reducing the stress concentration.
  • the termination does not include additional components or other additives.
  • the design is based on standard materials available at the inventor, and there is a potensial for optimalization for selecting stiffer polymer materials which include short fiber reinforced rubber.

Landscapes

  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Geology (AREA)
  • Architecture (AREA)
  • Civil Engineering (AREA)
  • Structural Engineering (AREA)
  • Mining & Mineral Resources (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Environmental & Geological Engineering (AREA)
  • Fluid Mechanics (AREA)
  • Physics & Mathematics (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Moulding By Coating Moulds (AREA)
  • Bending Of Plates, Rods, And Pipes (AREA)
  • Laying Of Electric Cables Or Lines Outside (AREA)

Abstract

L'invention se rapporte à un raidisseur antiflexion (1) qui est conçu pour être monté dans une station réceptrice, telle que de préférence une plate-forme en mer, pour le guidage de câbles, de tubes montants flexibles, d'ombilicaux, etc., à travers un passage axial interne (6) du raidisseur antiflexion (1). Ce raidisseur (1) comprend une extrémité de fin (14) par laquelle il est monté dans la station réceptrice, ainsi qu'une bride circulaire (3) ayant un passage interne qui est pourvue d'une pièce rapportée cylindrique interne (4) dont le passage interne a un diamètre égal à celui du passage interne (6) du raidisseur antiflexion (1). Une composition (7) à base d'un composé en caoutchouc avec un passage interne (6) et des dimensions externes ayant la même grandeur que le raidisseur antiflexion (1) est fixée à la pièce rapportée/bride terminale (2, 4) et elle est conçue de façon à présenter dans le sens longitudinal une conicité externe en direction de l'extrémité flexible (13) du raidisseur antiflexion (1). Cette composition (7) contient en outre des couches d'un renforcement axial (8) reliées par des couches de fils croisés (9) entre elles, un autre renforcement (11), ainsi qu'une couche de protection externe (12) enroulée autour de la circonférence externe du raidisseur antiflexion (1). La bride (2) est produite avec un certain nombre d'ouvertures radiales (fenêtres) (3) réparties autour de la bride (2). Le renforcement axial (8) s'étend depuis la partie flexible (13) du raidisseur antiflexion (1) jusqu'à atteindre une ouverture radiale (3) de la bride (2) et il revient ensuite vers la partie flexible (13) du raidisseur antiflexion (1) en passant dans une autre ouverture radiale (3) de la bride (2).
PCT/NO1993/000150 1992-10-08 1993-10-07 Raidisseur antiflexion WO1994009245A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
GB9507190A GB2286414B (en) 1992-10-08 1993-10-07 Bending stiffener
AU52872/93A AU5287293A (en) 1992-10-08 1993-10-07 Bending stiffener

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
NO923919A NO176368C (no) 1992-10-08 1992-10-08 Böyningsbegrensende anordning
NO92.3919 1992-10-08

Publications (1)

Publication Number Publication Date
WO1994009245A1 true WO1994009245A1 (fr) 1994-04-28

Family

ID=19895495

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/NO1993/000150 WO1994009245A1 (fr) 1992-10-08 1993-10-07 Raidisseur antiflexion

Country Status (4)

Country Link
AU (1) AU5287293A (fr)
GB (1) GB2286414B (fr)
NO (1) NO176368C (fr)
WO (1) WO1994009245A1 (fr)

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2741696A1 (fr) * 1995-11-29 1997-05-30 Coflexip Raidisseur pour une canalisation flexible a usage en milieu marin
FR2754011A1 (fr) * 1996-09-30 1998-04-03 Inst Francais Du Petrole Riser de production equipe d'un raidisseur approprie et d'un flotteur individuel
FR2760813A1 (fr) * 1997-03-14 1998-09-18 Coflexip Dispositif limiteur de courbure d'une conduite flexible
WO2007145532A1 (fr) * 2006-06-16 2007-12-21 Seaproof Solutions As Élément raidisseur renforcé par une matrice polymère et procédé de production correspondant
US7469722B2 (en) 2006-12-19 2008-12-30 Norvald Berland Segmented bend stiffener
FR2930618A1 (fr) * 2008-04-24 2009-10-30 Saipem S A Sa Element de conduite de transition d'inertie pour encastrement d'une conduite rigide sous-marine
CN103982742A (zh) * 2014-05-16 2014-08-13 大连理工大学 基于样条曲线的海洋柔性管缆防弯器
WO2017005278A1 (fr) * 2015-07-03 2017-01-12 Abb Schweiz Ag Dispositif de fixation de charge temporaire pour câble haute-tension blindé et procédé pour faciliter les opérations liées à l'installation d'un câble haute-tension blindé
EP3306031A1 (fr) 2016-10-05 2018-04-11 Nexans Extension de la durée de vie en fatigue
US10053921B2 (en) 2014-05-23 2018-08-21 Ge Oil & Gas Uk Limited Contact pressure limitation
WO2020223582A1 (fr) * 2019-05-02 2020-11-05 Pmi Industries, Inc. Limiteur de courbure constitué de segments séparés

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE60022059D1 (de) * 1999-07-23 2005-09-22 Nkt Flexibles I S Brondby Befestigung von verstärkungsdrähten an einem endabschnitt eines rohres oder seiles und verwendung des endabschnitts

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1496896A (en) * 1975-12-05 1978-01-05 Roberts & Armstrong Ltd Flexible conduits
EP0051091A1 (fr) * 1980-10-30 1982-05-12 Conoco Phillips Company Arrangement de colonnes montantes pour systèmes de production
NO155672B (no) * 1979-01-19 1987-01-26 Coflexip Boeyningsbegrensende anordning som kan monteres paa enden av en fleksibel roerledning.
EP0296056A1 (fr) * 1987-06-18 1988-12-21 Institut Français du Pétrole Elément à raideur variable pour pied de colonne de transfert

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1496896A (en) * 1975-12-05 1978-01-05 Roberts & Armstrong Ltd Flexible conduits
NO155672B (no) * 1979-01-19 1987-01-26 Coflexip Boeyningsbegrensende anordning som kan monteres paa enden av en fleksibel roerledning.
EP0051091A1 (fr) * 1980-10-30 1982-05-12 Conoco Phillips Company Arrangement de colonnes montantes pour systèmes de production
EP0296056A1 (fr) * 1987-06-18 1988-12-21 Institut Français du Pétrole Elément à raideur variable pour pied de colonne de transfert

Cited By (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0777034A1 (fr) * 1995-11-29 1997-06-04 Coflexip Raidisseur pour une canalisation flexible à usage en milieu marin
US6009907A (en) * 1995-11-29 2000-01-04 Coflexip Flexible stiffener
FR2741696A1 (fr) * 1995-11-29 1997-05-30 Coflexip Raidisseur pour une canalisation flexible a usage en milieu marin
FR2754011A1 (fr) * 1996-09-30 1998-04-03 Inst Francais Du Petrole Riser de production equipe d'un raidisseur approprie et d'un flotteur individuel
US5971075A (en) * 1996-09-30 1999-10-26 Institut Francais Du Petrole Production riser equipped with a suitable stiffener and with an individual float
FR2760813A1 (fr) * 1997-03-14 1998-09-18 Coflexip Dispositif limiteur de courbure d'une conduite flexible
WO1998041729A1 (fr) * 1997-03-14 1998-09-24 Coflexip Dispositif limiteur de courbure d'une conduite flexible
US6220303B1 (en) 1997-03-14 2001-04-24 Coflexip Device for limiting the bending radius of a flexible duct
US8033302B2 (en) 2006-06-16 2011-10-11 Seaproof Solutions As Polymer matrix reinforced stiffening element
WO2007145532A1 (fr) * 2006-06-16 2007-12-21 Seaproof Solutions As Élément raidisseur renforcé par une matrice polymère et procédé de production correspondant
US7469722B2 (en) 2006-12-19 2008-12-30 Norvald Berland Segmented bend stiffener
FR2930618A1 (fr) * 2008-04-24 2009-10-30 Saipem S A Sa Element de conduite de transition d'inertie pour encastrement d'une conduite rigide sous-marine
WO2009138610A1 (fr) * 2008-04-24 2009-11-19 Saipem S.A. Element de conduite de transition d'inertie notamment pour encastrement d'une conduite rigide sous-marine
US8844632B2 (en) 2008-04-24 2014-09-30 Saipem S.A. Inertia transition pipe element, in particular for restraining a rigid undersea pipe
CN103982742A (zh) * 2014-05-16 2014-08-13 大连理工大学 基于样条曲线的海洋柔性管缆防弯器
US10053921B2 (en) 2014-05-23 2018-08-21 Ge Oil & Gas Uk Limited Contact pressure limitation
WO2017005278A1 (fr) * 2015-07-03 2017-01-12 Abb Schweiz Ag Dispositif de fixation de charge temporaire pour câble haute-tension blindé et procédé pour faciliter les opérations liées à l'installation d'un câble haute-tension blindé
US10498126B2 (en) 2015-07-03 2019-12-03 Nkt Hv Cables Gmbh Temporary load securing device for an armoured high voltage cable and a method for facilitating installation-related operations of an armoured high voltage cable
AU2015401841B2 (en) * 2015-07-03 2020-04-09 Nkt Hv Cables Ab A temporary load securing device for an armoured high voltage cable and a method for facilitating installation-related operations of an armoured high voltage cable
EP3306031A1 (fr) 2016-10-05 2018-04-11 Nexans Extension de la durée de vie en fatigue
WO2020223582A1 (fr) * 2019-05-02 2020-11-05 Pmi Industries, Inc. Limiteur de courbure constitué de segments séparés
CN113785149A (zh) * 2019-05-02 2021-12-10 Pmi工业有限公司 分体式分节段的限弯器

Also Published As

Publication number Publication date
GB9507190D0 (en) 1995-05-31
NO923919D0 (no) 1992-10-08
GB2286414A (en) 1995-08-16
NO923919L (no) 1994-04-11
NO176368B (no) 1994-12-12
NO176368C (no) 1995-03-22
AU5287293A (en) 1994-05-09
GB2286414B (en) 1996-03-06

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