NO844729L - PROCEDURE FOR AA ESTABLISH A CONNECTION FROM THE SEA SOUND TO AN UNDERLYED TUNNEL. - Google Patents

PROCEDURE FOR AA ESTABLISH A CONNECTION FROM THE SEA SOUND TO AN UNDERLYED TUNNEL.

Info

Publication number
NO844729L
NO844729L NO844729A NO844729A NO844729L NO 844729 L NO844729 L NO 844729L NO 844729 A NO844729 A NO 844729A NO 844729 A NO844729 A NO 844729A NO 844729 L NO844729 L NO 844729L
Authority
NO
Norway
Prior art keywords
drilling
tunnel
seabed
template
drill
Prior art date
Application number
NO844729A
Other languages
Norwegian (no)
Inventor
Bjoern Halmrast
Original Assignee
Selmer As Ing F
Amr Engineering
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 Selmer As Ing F, Amr Engineering filed Critical Selmer As Ing F
Priority to NO844729A priority Critical patent/NO844729L/en
Priority to EP85906091A priority patent/EP0202310A1/en
Priority to AU51940/86A priority patent/AU5194086A/en
Priority to PCT/NO1985/000073 priority patent/WO1986003253A1/en
Priority to CU1985213A priority patent/CU21793A3/es
Publication of NO844729L publication Critical patent/NO844729L/en

Links

Classifications

    • 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
    • E21B43/00—Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells
    • E21B43/30—Specific pattern of wells, e.g. optimising the spacing of wells
    • E21B43/305—Specific pattern of wells, e.g. optimising the spacing of wells comprising at least one inclined or horizontal well
    • 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
    • E21B41/00—Equipment or details not covered by groups E21B15/00 - E21B40/00
    • E21B41/08—Underwater guide bases, e.g. drilling templates; Levelling thereof
    • 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
    • E21B7/00—Special methods or apparatus for drilling
    • E21B7/04—Directional drilling
    • E21B7/043—Directional drilling for underwater installations
    • 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
    • E21B7/00—Special methods or apparatus for drilling
    • E21B7/12—Underwater drilling
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00—Energy generation through renewable energy sources
    • Y02E10/30—Energy from the sea, e.g. using wave energy or salinity gradient

Landscapes

  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Geology (AREA)
  • Mining & Mineral Resources (AREA)
  • Physics & Mathematics (AREA)
  • Environmental & Geological Engineering (AREA)
  • Fluid Mechanics (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Earth Drilling (AREA)
  • Building Environments (AREA)

Description

Foreliggende oppfinnelse angår en fremgangsmåte for etablering av en forbindelse fra havbunnen til en på forhånd utsprengt eller utboret tunnel. Slike tunnelforbindelser er det behov for i såkalte havtermiske kraftanlegg, som produserer energi ved å utnytte temperaturdifferansen mellom overflate-vannet og vannet på store dyp. The present invention relates to a method for establishing a connection from the seabed to a previously blasted or excavated tunnel. Such tunnel connections are needed in so-called marine thermal power plants, which produce energy by utilizing the temperature difference between the surface water and the water at great depths.

Ved bygging av kraftanlegg av den konvensjonelle typeWhen building power plants of the conventional type

er det f.eks. vanlig å etablere en forbindelse mellom en under-vanns-fjelltunnel og en sjø ved at den siste del av tunnelen d.v.s. tunnelens frontparti sprenges fra innsiden d.v.s. fra luftsiden, og stenmasser fra sprengningen oppfanges av en utsprengt grop inne i tunnelen. Usikkerheten ved metoden øker med vanndybden, og på dyp på flere hundre meter ansees metoden ikke sikker nok med hensyn til gjennomføringen, spesielt med tanke på vannleka-sjer i den siste del av tunneldriften. Det er derfor nødvendig å utvikle en metode hvor den konvensjonelle tunneldriften kan avsluttes i betryggende avstand fra selve fjelloverflaten på sjøbunnen. is it e.g. common to establish a connection between an underwater mountain tunnel and a sea by having the last part of the tunnel, i.e. the front part of the tunnel is blown up from the inside, i.e. from the air side, and masses of rock from the blasting are collected by a blasted pit inside the tunnel. The uncertainty of the method increases with the water depth, and at depths of several hundred meters the method is not considered safe enough with regard to implementation, especially with regard to water leaks in the last part of the tunnel operation. It is therefore necessary to develop a method where the conventional tunnel operation can be terminated at a safe distance from the actual rock surface on the seabed.

I forbindelse med oljeutvinning fra havbunnen er det tidligere kjent å avslutte en tunnel i avstand fra havbunnflaten og tette tunnelens frontparti fra resten av tunnelen for deretter å bore seg fra tunnelens innside gjennom den resterende del av sjøbunnberget. I det således utborede borehull>trekkes det fra utsiden en rørledning. Rørledningens diameter er ubetyde-lig i forhold til tunnelens. In connection with oil extraction from the seabed, it has previously been known to terminate a tunnel at a distance from the seabed surface and seal off the front part of the tunnel from the rest of the tunnel and then drill from the inside of the tunnel through the remaining part of the seabed rock. In the borehole drilled in this way, a pipeline is drawn from the outside. The pipeline's diameter is insignificant compared to the tunnel's.

Formålet med oppfinnelsen er å gjøre det mulig på en sikker måte å etablere en forbindelse av den innledningsvis nevnte art hvis gjennomstrømningstverrsnitt i hydraulisk henseende stort sett svarer til tunnelens tverrsnitt. Hensikten med oppfinnelsen oppnåes ved at det fra havbunnflaten bores et antall borehull som slutter i tunnelen og som har et totalt gjennom-strømningstverrsnitt som i hydrodynamisk henseende i det minste svarer til tunnelens tverrsnitt. For opphevelse av den store trykkdifferensen mellom vannsiden og luftsiden fylles tunnelen før gjennomslaget med vann. Boringen utføres fortrinnsvis fra en flytende eller halv nedsenket borerigg e.l. og det benyttes boremal til styring av borestrengen. Fremgangsmåten ifølge oppfinnelsen er anvendelig både for vertikal boring og skrå boring. The purpose of the invention is to make it possible in a safe way to establish a connection of the type mentioned at the outset whose flow cross-section in hydraulic terms largely corresponds to the tunnel's cross-section. The purpose of the invention is achieved by drilling a number of boreholes from the seabed surface which terminate in the tunnel and which have a total flow-through cross-section which, in hydrodynamic terms, at least corresponds to the tunnel's cross-section. To eliminate the large pressure difference between the water side and the air side, the tunnel is filled with water before the penetration. The drilling is preferably carried out from a floating or semi-submerged drilling rig or the like. and a drill template is used to control the drill string. The method according to the invention is applicable both for vertical drilling and inclined drilling.

Oppfinnelsen løser problemet med den tidligere kjente utslagsmetode på en enkel og sikker måte. I stedet for å foreta utslaget fra 'innsiden foretas gjennomslaget ved oppboring fra yttersiden, d.v.s. fra vannsiden. Herved oppnåes at tunnel-arbeidene kan avsluttes i tilstrekkelig og trygg avstand fra fjelloverflaten. The invention solves the problem with the previously known knock-out method in a simple and safe way. Instead of making the cut from the inside, the cut is made by drilling from the outside, i.e. from the water side. This ensures that the tunnel works can be completed at a sufficient and safe distance from the mountain surface.

Oppfinnelsen skal forklares nærmere nedenfor ved hjelp av eksempler og under henvisning til tegninger, hvor The invention shall be explained in more detail below by means of examples and with reference to drawings, where

fig. 1 illustrerer skjematisk vertikal boring for oppnåelse av en tunnelforbindelse i samsvar med oppfinnelsen, fig. 2 illustrerer skrå boring, fig. 3 illustrerer montering av borestrengen for skrå boring og fig. 4 viser skjematisk en boremal med føringstrakt. fig. 1 schematically illustrates vertical drilling for obtaining a tunnel connection in accordance with the invention, fig. 2 illustrates inclined drilling, fig. 3 illustrates assembly of the drill string for oblique drilling and fig. 4 schematically shows a drilling template with guide funnel.

Fig. 1 viser et vertikalsnitt av en kaldtvannstunnelFig. 1 shows a vertical section of a cold water tunnel

for et havtermisk kraftanlegg. For et kraftanlegg på f.eks.for an ocean thermal power plant. For a power plant of e.g.

5 MW kan det være aktuelt med en tunnel for inntak av kaldt vann med et tverrsnitt på ca. 20 m 2. På figuren er 1 fjelloverflaten (havbunnoverflaten), 2 er fjell-tunnelen, den vertikale sjakten, 3 er den horisontale del av tunnelen. 4 betegner en alternativ, krummet tunnel. Oppboringen av forbindelsen til tunnelen skjer ved hjelp av et boreskip eller en halvt nedsenkbar boreplattform, betegnet 5. Denne forankres over borestedet, f.eks. ved hjelp av dynamisk posisjonering. Selve ansettet av borehullene utføres fortrinnsvis ved hjelp av en på forhånd innstillet stålramme 6 med sentreringsanordninger for borestrengen 7. Antall borehull 8 bestemmes av nødvendig tverrsnittsbehov. En grop for borekaks og eventuelle sprengrester er vist ved 9. Vanlig største diameter i petroleumsindustrien er for tiden 36", d.v.s. for en 20 m 2 tverrsnitt trengs ca. 25-30 hull. Hull-lengden vil være avhengig av geometrien på fjelloverflaten og tunnelens beliggen-het. 5 MW, it may be relevant to have a tunnel for intake of cold water with a cross-section of approx. 20 m 2. In the figure, 1 is the rock surface (seabed surface), 2 is the rock tunnel, the vertical shaft, 3 is the horizontal part of the tunnel. 4 denotes an alternative, curved tunnel. The connection to the tunnel is drilled using a drilling ship or a semi-submersible drilling platform, denoted 5. This is anchored above the drilling site, e.g. using dynamic positioning. The actual placement of the drill holes is preferably carried out using a pre-set steel frame 6 with centering devices for the drill string 7. The number of drill holes 8 is determined by the required cross-section. A pit for drilling cuttings and any blasting debris is shown at 9. The usual largest diameter in the petroleum industry is currently 36", i.e. for a 20 m 2 cross-section approx. 25-30 holes are needed. The hole length will depend on the geometry of the rock surface and the tunnel's location.

Ved en hensiktsmessig plassering av utslagsstedet vil oppboringen av hullene kunne utføres raskt, effektivt og rimelig, With an appropriate location of the tee, the drilling of the holes can be carried out quickly, efficiently and inexpensively,

og fremfor alt sikkert.and above all safe.

Fig. 2 illustrerer en alternativ fremgangsmåte, hvor borehullene 8 bores på skrå for å oppnå bedre strømningsforhold ved innløpet til selve tunnelen 3 hhv. gropen eller bergrommet 9. Det fremgår av figuren at bergrommets utstrekning er forholdsvis stor i forhold til tunnelens tverrsnitt. Derved er det skaffet en bedre mulighet for hensiktsmessig plassering av et stort antall borehull og dermed bedre vanntilførsel og bedre hydrauliske forhold ved innløpet til tunnelen. Det fremgår også av figuren at boremalen 6 er utstyrt med en føringstrakt 10 som er sving-bart lagret ved 11. Borestrengen forløper langs en buet bane fra boreriggen 5 til malens føringstrakt 10 slik at borestrengens nederste parti med borekronen er i flukt med den tilsiktede boreretning. Malen kan være utført med like mange føringer som det skal bores hull i havbunnen, men den kan også være utstyrt med en eller flere føringer som kan beveges på langs og tvers av boremalerammen. Slike boremal er kjent fra vertikal boring på stort sett horisontal havbunn. Føringstrakten 10 kan eventuelt være anordnet for rotasjon slik at man får et sirkelformet borehullmønster. Fig. 3 illustrerer en fremgangsmåte for tilpasning av borestrengen for skrå boring. Boreballen 6 er utstyrt med en føringstrakt 10 for oppfanging av borestrengens nederste del (se også fig. 4). I posisjon I befinner boreriggen seg rett overfor føringstrakten og borekronen føres inn i trakten som følge av borestrengens tyngde. Deretter flyttes boreriggen til posisjon II samtidig som det settes nye seksjoner på borestrengen mens føringstrakten 10 dreies for oppnåelse av riktig ansats-vinkel. Et hjelpefartøy 12 hjelper til å holde borekronen på plass under forflytningen av boreriggen. Fig. 4 viser skjematisk en boremalramme 6 utført som slede for forskyvning langs havbunnen og utstyrt med en sving-bar føringstrakt 10 som vist på fig. 2. Fig. 2 illustrates an alternative method, where the boreholes 8 are drilled at an angle to achieve better flow conditions at the entrance to the tunnel itself 3 or the pit or rock space 9. It is clear from the figure that the extent of the rock space is relatively large in relation to the tunnel's cross-section. Thereby, a better opportunity has been obtained for the appropriate placement of a large number of boreholes and thus better water supply and better hydraulic conditions at the entrance to the tunnel. It also appears from the figure that the drill template 6 is equipped with a guide funnel 10 which is pivotably stored at 11. The drill string runs along a curved path from the drilling rig 5 to the template guide funnel 10 so that the bottom part of the drill string with the drill bit is flush with the intended drilling direction . The template can be made with as many guides as there are holes to be drilled in the seabed, but it can also be equipped with one or more guides that can be moved along and across the drill template frame. Such drill templates are known from vertical drilling on a largely horizontal seabed. The guide funnel 10 can optionally be arranged for rotation so that a circular borehole pattern is obtained. Fig. 3 illustrates a method for adapting the drill string for inclined drilling. The drill ball 6 is equipped with a guide funnel 10 for catching the bottom part of the drill string (see also fig. 4). In position I, the drilling rig is located directly opposite the guide hopper and the drill bit is guided into the hopper as a result of the weight of the drill string. The drilling rig is then moved to position II at the same time as new sections are placed on the drill string while the guide funnel 10 is rotated to achieve the correct approach angle. An auxiliary vessel 12 helps to hold the drill bit in place during the movement of the drilling rig. Fig. 4 schematically shows a drill template frame 6 designed as a sled for displacement along the seabed and equipped with a pivotable guide funnel 10 as shown in fig. 2.

Claims (7)

1. Fremgangsmåte for å etablere en fullprofil-forbindelse mellom havbunnen og en under havbunnen beliggende tunnel eller en del av samme, særlig på stor havdybde, der tunnelen sprenges og/eller bores i bergarten med frontpartiet så nær som mulig havbunnflaten uten at personell og utstyr utsettes for fare, karakterisert ved at forbindelsen tilveiebringes ved at det fra havbunnflaten bores et antall borehull som slutter i tunnelen og som har et totalt gjennomstrømningstverrsnitt som i hydrodynamisk henseende i det minste svarer til tunnelens tverrsnitt.1. Procedure for establishing a full-profile connection between the seabed and a tunnel located below the seabed or part of the same, particularly at great sea depth, where the tunnel is blasted and/or drilled into the rock with the front part as close as possible to the seabed surface without personnel and equipment exposed to danger, characterized by the fact that the connection is provided by drilling a number of boreholes from the seabed surface which terminate in the tunnel and which have a total flow cross-section which, in hydrodynamic terms, at least corresponds to the tunnel's cross-section. 2. Fremgangsmåte ifølge krav 1, karakterisert ved at tunnelen før gjennomslaget fylles med vann for utjevning av trykket.2. Method according to claim 1, characterized in that the tunnel is filled with water before penetration to equalize the pressure. 3. Fremgangsmåte ifølge krav 1 eller 2, karakterisert ved at tunnelens frontparti før boringsoperasjonen utvides med et bergrom for opptak av borekaks-og sprengrester og/eller for hensiktsmessig plassering av borehullene i forhold til tunnelen.3. Method according to claim 1 or 2, characterized in that the front part of the tunnel is expanded before the drilling operation with a storage room for the reception of drilling cuttings and blasting residues and/or for appropriate placement of the boreholes in relation to the tunnel. 4. Fremgangsmåte ifølge krav 1 eller 2, karakterisert ved at boringen skjer fra en flytende borerigg e.l. under anvendelse av boremal (template) som til-passes etter havbunnen,slik at målfø ringene under bruk forløper i det vesentlige perpendikulært.4. Method according to claim 1 or 2, characterized in that the drilling takes place from a floating drilling rig or the like. using a drilling template (template) which is adapted to the seabed, so that the target guides run essentially perpendicularly during use. 5. Fremgangsmåte ifølge krav 1, 2 eller 3, karakterisert ved at boringen skjer fra en flytende borerigg e.l. under anvendelse av boremal (template)som til-passes etter havbunnen, slik at målføringene under bruk stort sett forløper vinkelrett på havbunnen.5. Method according to claim 1, 2 or 3, characterized in that the drilling takes place from a floating drilling rig or the like. using a drilling template (template) which is adapted to the seabed, so that the target guides during use mostly run perpendicular to the seabed. 6. Fremgangsmåte ifølge krav 5, karakterisert ved at boremal med svingbar(e) innføringstrakt(er) anvendes.6. Method according to claim 5, characterized in that a drilling template with pivotable introduction funnel(s) is used. 7. Fremgangsmåte ifølge krav 6 for boring på skrå i hellende havbunn, karakterisert ved at boreriggene e.l. først plasseres rett over boremalens innføringstrakt og borstren-gens kroneparti anbringes i denne, hvoretter boreriggen for-flyttes til en ny stilling idet borestrengen bøyes slik at borkronepartiet kommer i flukt med den tilsiktede boreretning, idet føringstrakten svinges tilsvarende under forflytningsoperasjo-nen .7. Method according to claim 6 for drilling at an angle in sloping seabed, characterized in that the drilling rigs etc. first, it is placed directly above the introduction funnel of the drill bit and the crown part of the drill string is placed in this, after which the drill rig is moved to a new position while the drill string is bent so that the drill bit part aligns with the intended drilling direction, as the guide hopper is swung accordingly during the transfer operation.
NO844729A 1984-11-28 1984-11-28 PROCEDURE FOR AA ESTABLISH A CONNECTION FROM THE SEA SOUND TO AN UNDERLYED TUNNEL. NO844729L (en)

Priority Applications (5)

Application Number Priority Date Filing Date Title
NO844729A NO844729L (en) 1984-11-28 1984-11-28 PROCEDURE FOR AA ESTABLISH A CONNECTION FROM THE SEA SOUND TO AN UNDERLYED TUNNEL.
EP85906091A EP0202310A1 (en) 1984-11-28 1985-11-27 A method for establishing a connection from the sea bed to a tunnel positioned below
AU51940/86A AU5194086A (en) 1984-11-28 1985-11-27 Fremgangsmate for a etablere en forbindelse fra havbunnen til en underliggende tunnel
PCT/NO1985/000073 WO1986003253A1 (en) 1984-11-28 1985-11-27 A method for establishing a connection from the sea bed to a tunnel positioned below
CU1985213A CU21793A3 (en) 1984-11-28 1985-11-28

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
NO844729A NO844729L (en) 1984-11-28 1984-11-28 PROCEDURE FOR AA ESTABLISH A CONNECTION FROM THE SEA SOUND TO AN UNDERLYED TUNNEL.

Publications (1)

Publication Number Publication Date
NO844729L true NO844729L (en) 1986-05-29

Family

ID=19887963

Family Applications (1)

Application Number Title Priority Date Filing Date
NO844729A NO844729L (en) 1984-11-28 1984-11-28 PROCEDURE FOR AA ESTABLISH A CONNECTION FROM THE SEA SOUND TO AN UNDERLYED TUNNEL.

Country Status (5)

Country Link
EP (1) EP0202310A1 (en)
AU (1) AU5194086A (en)
CU (1) CU21793A3 (en)
NO (1) NO844729L (en)
WO (1) WO1986003253A1 (en)

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NO139063C (en) * 1976-02-13 1978-12-27 Norske Stats Oljeselskap PROCEDURE AND PIPE CONSTRUCTION FOR ESTABLISHING A CONNECTION BETWEEN A FRALAND PIPELINE AND A TUNNEL UNDER THE SEAM
CA1051676A (en) * 1977-08-25 1979-04-03 John A. Owen Tunnel

Also Published As

Publication number Publication date
EP0202310A1 (en) 1986-11-26
WO1986003253A1 (en) 1986-06-05
CU21793A3 (en) 1993-10-01
AU5194086A (en) 1986-06-18

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