Key information

Title
Method of perforating, washing, cementing, and cutting and pulling a casing
Application number
20210361
Case type
National
Status
19.10.2026 Patent meddelt (B1)
Filed
19.03.2021
Effective date
19.03.2021
Publicly available
20.09.2022
Next annual fee due
31.03.2027
Applicant
Archer Oiltools AS (NO)
Owner
Archer Oiltools AS (NO)
Inventor
Bjørn Tore Torvestad (NO)
Agent
BRYN AARFLOT AS (NO)
Granted
19.10.2026
Patent number
350232
Expiry date
19.03.2041

Abstract and drawing

Disclaimer: This text has been machine-scanned and may contain errors – please refer to "Publications" for legally binding content.
A well intervention tool string comprising from top to bottom: - a drill pipe string, - a through bore spear plug tool (10, 10’), comprising a packer and a switchable ball valve having a bore > 5,08 cm (2'') diameter, - a space-out drill pipe string, - a through bore cutter tool (20), comprising a fourth ball seat (22) arranged for receiving a fourth ball (22B) arranged for building up pressure in the cutter tool (20) in order to extend knives (24), - a swivel (30) below the cutter tool (20), - a swab cup wash tool (40), a second and third ball seat (42, 43) arranged for receiving a second and third ball (42B, 43B) below the swab cup washer tool (40), said swab cup wash tool (40) further being provided with a bypass line (44) across its swab cups (46), said swab cup wash tool (40) being arranged for washing a perforated annulus and said swab cup wash tool being arranged for subsequently cementing a perforated casing, cement passing back in through the perforations and passing through the bypass line (44) to cement a casing main bore, - a perforation gun (50) comprising a first ball seat (52) in a firing head (52) and Automatic Gun Release (AGR) (54) for the perforation gun (50).

Publications

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Documents

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Date
 Date Doc. No. Process Case number In/Out Journal description To/from
 20.10.2026 09-01 Saksbehandling 20210361(350232) UT PT Registreringsbrev nasjonal patent (15) (PT20210361)
12.08.2026 08-01 Saksbehandling 20210361 UT Intention to grant BRYN AARFLOT AS
 08.02.2024 02-01 Endring av fullmektig 2024/01845 UT GH Forespørsel BRYN AARFLOT AS
 06.02.2024 01-02 Endring av fullmektig 2024/01845 INN GPOA signed BRYN AARFLOT AS
 06.02.2024 01-01 Endring av fullmektig 2024/01845 INN Generell henvendelse BRYN AARFLOT AS
 06.05.2022 07-07 Saksbehandling 20210361 INN P19948NO00 Claims translated ACAPO AS
 06.05.2022 07-06 Saksbehandling 20210361 INN P19948NO00 Besvarelse ACAPO AS
 06.05.2022 07-05 Saksbehandling 20210361 INN P19948NO00 Amended description ACAPO AS
 06.05.2022 07-04 Saksbehandling 20210361 INN P19948NO00 Amended description clean ACAPO AS
 06.05.2022 07-03 Saksbehandling 20210361 INN P19948NO00 Amended claims ACAPO AS
 06.05.2022 07-02 Saksbehandling 20210361 INN P19948NO00 Amended claims clean ACAPO AS
 06.05.2022 07-01 Saksbehandling 20210361 INN Korrespondanse (Hovedbrev inn) ACAPO AS
 19.04.2022 06-05 Saksbehandling 20210361 INN P19948NO00 Besvarelse Patentstyret ACAPO AS
 19.04.2022 06-04 Saksbehandling 20210361 INN P19948NO00 Amended Claims Work ACAPO AS
 19.04.2022 06-03 Saksbehandling 20210361 INN P19948NO00 Amended Claims Clean ACAPO AS
 19.04.2022 06-02 Saksbehandling 20210361 INN P19948NO00 Amend Drawings ACAPO AS
 19.04.2022 06-01 Saksbehandling 20210361 INN Korrespondanse (Hovedbrev inn) ACAPO AS
 18.10.2021 05-02 Saksbehandling 20210361 UT PT report 05:35:07
18.10.2021 05-01 Saksbehandling 20210361 UT Substantive examination ACAPO AS
 10.06.2021 04-03 Saksbehandling 20210361 INN Signert generalfullmakt Archer ACAPO AS
 10.06.2021 04-02 Saksbehandling 20210361 INN P19948NO00 - signert overdragelse ACAPO AS
 10.06.2021 04-01 Saksbehandling 20210361 INN Korrespondanse (Hovedbrev inn) ACAPO AS
 22.03.2021 03-01 Saksbehandling 20210361 UT Formal Examination 1 ACAPO AS
 22.03.2021 02-01 Saksbehandling 20210361 UT Infobrev til oppfinner ACAPO AS
 19.03.2021 01-03 Saksbehandling 20210361 INN P19948GB00 PWCC 19 Mar 2021 to be filed ACAPO AS
 19.03.2021 01-02 Saksbehandling 20210361 INN Description and claims to file 19 march 2021 ACAPO AS
 19.03.2021 01-01 Saksbehandling 20210361 INN Søknadsskjema Patent ACAPO AS

Description, claims and drawings

Disclaimer: This text has been machine-scanned and may contain errors – please refer to "Publications" for legally binding content. Description
P19948NO00 to be filed in Norway 19.03.2021 Components and Definitions:P19948NO00 to be filed in Norway 19.03.2021IntroductionThe present invention relates to a plug and abandon operation with a pulling out of a casing from the well. The perforate, wash and cementing operation of the invention utilises in an embodiment the applicant's Barricade system, a single trip system to perforate a casing wall, wash the casing annulus, and circulate in cement to the annulus to establish a cement barrier across a geological formation, here the Shetland Group formation. In an embodiment the invention’s operation makes use ofA 9-5/8” "Stronghold Barricade System" – or more generalized, an annulus wash tool (40) also used for annulus cementing.A 9-5/8” "SAMURAI MF Cutter" – or more generally a casing cutter tool (20) which has a through bore which may also be cemented through.A 9-5/8” "Spearhead Plug" - a spear and plug tool which is enabled to hang off drill pipe string below, or more generalized, a spear tool (10) which has a main through bore which may be circulated through the main bore.According to regulations for abandoning a petroleum well, a dual barrier is required. In an example, illustrated in the left column of Fig. A1, B1, and C1, Please also see Fig. A2, B2, and C2, 254ft of perforations will be made and a 600ft cased hole cement plug will be placed within a 9-5/8” casing. This is for a well called BC-07, and other depths may be relevant for other wells, but the example illustrates the problem to be solved.The geological formation to be plugged in the example is the Shetland formation between depths: 6,831ft – 9,436ft BHR MD at 31° inclination.The top of the completion packer is at 8,700ft BHR MD.The planned perforation depth is 8,027ft – 8,281ft BHR MD (254ft) with a further 346ft internal cased hole plug covering 7,681ft – 8,027ft MD to ensure the combined plug (600ft) covers the parts of the Shetland Group formation that needs be plug cemented.In an embodiment of the invention a wireline set plug is set at 8,578ft BHR to allow a sump to drop the TCP BHA into.Drill string to be used is 5” NC50 drill pipe to surface.Brief summary of the inventionThe invention is defined in the attached set of claims.Brief Figure CaptionsThe invention is illustrated in the attached Drawing Figures. The Figures have been drawn in three corresponding series A1 – A11, B1 – B11, and C1 – C11, which differ in the following aspects: P19948NO00 to be filed in Norway 19.03.2021- whether a spear tool (10) is in the original toolstring, please see Fig. A1 – A11, - whether the spear tool (10) is not in the initial tool string but inserted after the cut has been made, please see Fig. B1 – B11, and- further whether the whether the spear tool (10) is a spear plug tool (10’), and is not in the initial tool string but inserted after the cut has been made, please see Fig. C1 – C11.Figs. A1, B1, and C1 illustrate the toolstring run into a well to above a rathole above a bridge plug , and fires a perforation gun to perforate a desired interval of a casing to be cemented. To the left is a depth indicator column for the exemplary well referred to in the Appendix, with a sandstone formation drawn in.Figs. A2, B2, and C2 illustrate a wash tool (40) washing the annulus of the perforated casing section. The wash fluid is run through the through bore (spear tool (10), cutter tool (20), swivel (30), and out radially from the wash tool (40).Figs. A3, B3, and C3 illustrate a situation after the wash tool (40) has cemented the washed out annulus and the main bore and formed a rock to rock cement plug. Now we may wait on the cement to harden and set in order to pressure test the formed cement plug from above. The wash tool is not capable of dressing and tagging the cement plug so we conduct a pressure test from above.Figs. A4, B4, and C4 illustrate the employment of cutter tool (20) knives making a rotational cut through the casing to form a severed-off casing section above the cut to be pulled out of hole eventually.Figs. A5, B5, and C5 illustrate pulling up the cutter tool (20), the swivel (30) and the wash tool (40) to above the cut, and start preparing for test pulling of the severed-off casing section.Fig. A6 merely illustrates that it is not required to pull up and insert a spear tool (10) because it is already in the toolstring.Fig. B6 and C6 illustrate pulling up and inserting a spear tool (10) and a spear plug tool (10’) respectively.Fig. A7 illustrates that it is not required to run the spear tool (10) down to the top of the casing, it was in place in Fig. A5 already.Fig. B7 and C7 illustrate that the newly inserted spear tool (10) and spear plug tool (10’) are run into hole, respectively, to the top of the severed-off casing, and with the cutter tool (20), swivel (30) and wash tool (40) in place below, well off the cut.Fig. A8, B8, and C8 illustrate the common feature that the spear tool (10) in Figs. A8 and B8, and the spear plug tool (10’) in Fig. C8, are set and used to conduct a test pull to check whether the severed-off casing section is free to pull. P19948NO00 to be filed in Norway 19.03.2021Fig. A9, Fig. B9, and Fig. C9 illustrate that the the spear tool (10) or spear plug tool (10’) are laid out, the cutter tool (20), swivel (30) and wash tool (40) are laid out. Those would otherwise interfere with the coming pull-out process of the severed-off casing section. Fig. A10, B10, and C10 show insertion of a spear tool (10) or spear plug tool (10’), respectively, and running it down to the top of the severed-off casing.Fig. A11, B11, and C11 show pulling out of the severed-off casing section, and further operations such as sidetracking or permanent abandonment of the well may be conducted.Embodiments of the inventionThe invention provides a well intervention toolstring comprising from top to bottom:- a drill pipe string (0) extending from a surface rig with a drilling motor,- a through bore spear (10),- space-out drill pipe string (00),- a through bore cutter tool (20),- a swivel (30) below the cutter tool (20),- a swab cup wash tool (40) ,- a perforation gun (50).The through bore spear (10) is arranged for engaging and pulling on casing pipe, in this case a casing pipe section having been severed at a desired depth, as illustrated in Figs. A4, B4, C4.In an embodiment the spear (10) is a drill-pipe conveyed spear tool (10) with slips setting in a casing pipe, please see Figs. A1 to A11. In that embodiment the spear tool (10) may be in the original drill pipe string, a casing spear (10).In an embodiment the spear tool (10) is not in the original tool string first run into the well, please see Figs. B1 – B11. but inserted after the cut has been made, please see Fig. B6. In another embodiment the spear (10) is in the form of a casing hanger running tool.In yet another embodiment the spear (10) is in the form of a spear plug tool (10’) with capacity for holding the remaining toolstring of cutter tool (20), swivel (30) and wash tool (40) below the spear. Such a spear plug tool (10’) which has a packer may be used for, in addition to pulling on the severed-off casing section, also to be set under pressure via the drill pipe string, the pressure now directed upwardly from below, also via the cut, in order to create a piston effect from below on the severed-off casing section.Fourth ball seatIn an embodiment of the invention the through bore cutter tool (20) has a fourth ball seat (22) arranged for receiving a fourth ball (22B) arranged for building up pressure in the cutter tool (20) in order to extend knives (24), please see Figs. A4, B4, and C4. The reason for naming it the fourth ball seat (22) is that there are three ball seats arranged below, one in the perforation gun (50), and two in the wash tool (40), which are utilized before the cutter tool ball seat. P19948NO00 to be filed in Norway 19.03.2021Wash toolIn an embodiment of the invention the the swab cup wash tool (40) further has a bypass line (44) across the wash tool (40) swab cups (46).The wash tool (40) is arranged for washing the perforated annulus.The wash tool (40) is arranged for subsequently cementing the perforated casing annulus, cement passing back in through the perforations and passing through the bypass line (44) to cement the casing main bore, as described in Sverre Bakken’s patent EP3036395 on a combined annulus wash and cementing method.Third and second ball seatsIn an embodiment of the invention there is a second and third ball seat (42, 43) below the swab cup wash tool (40). The second and third ball seat (42, 43) are arranged for receiving a second and third ball (42B, 43B). The second ball seat (42) may be sheared out at a predetermined pressure after the annulus washing procedure, and the third ball seat (43) is sheared out after the cementing circulation procedure for cementing the annulus of the perforated casing, and also for cementing the main bore below the washing tool during the pump and pull operation. Details of the washing and cementing procedures are given in the below appendix.First ball seatIn an embodiment of the invention the well intervention, the toolstring further comprises a first ball seat (52) in a firing head (53) and an automatic gun release AGR (54) for the perforation gun (50). The first ball (52B) is dropped to the first ball seat (52), landed, and pressure is set to trigger the firing head (53) which sets off all the guns (50) in common, and activates the automatic gun release (54) to drop the guns into the below rathole above the wireline set plug or other basis for the cementing operation.Spear plug embodimentIn an embodiment shown in Figs C1 – C11, the through bore spear (10) is a spear plug tool (10') which comprises a packer and further comprises a switchable ball valve having a bore of relatively large diameter to allow circulation through.The method of the inventionThe method provides a method for pulling a casing as illustrated in Figs. A1, B1, C1 to A11, B11, C11. The method comprises the steps of:- assembling the toolstring of the invention as illustrated in Fig. A1. In an embodiment of the invention the toolstring is assembled except for the spear (10, 10’) as illustrated in Figs. B1 and C1, but introduces it in the step of Fig. B6 and C6.- run the toolstring into hole and place the perforation gun (50) at a predetermined perforation depth, as illustrated in Figs. A1, B1, and C1,- perforate the casing using the perforation gun (50), wherein the result is illustrated in Figs. A2, B2, and C2 between u. perf. And L. perf. One may in an embodiment use other perforation tools (50) than a gun, such as a perforation tool which makes one by one perforation, which just takes longer time than a single-firing long gun, bot otherwise provides a perforated section of the casing. P19948NO00 to be filed in Norway 19.03.2021- subsequently, wash the perforated casing annulus using the swab cup wash tool (40), please see Figs. A2, B2, and C2, and- circulate in cement into the washed-out casing annulus and the casing bore preferably using the swab cup wash tool (40), please see Fig. A2, B2, and C2, with the resulting plug illustrated in Figs. A3, B3, and C3. In an embodiment it would be possible to place cement in the main bore and squeeze it into the washed-out casing annulus, but circulating it in using the wash tool better fills the washed-out annulus. The well is now cemented rock-to-rock with the perforated casing as a steel reinforcement in the cement plug, please see Fig. A3, B3, C3.- After cementing, pull up and wait on cement as illustrated in Fig. A3, B3, C3, and pressure test the cement plug formed.- Subsequently, pull up the toolstring with the cutter tool knives to the desired shallower depth, and cut the casing at the shallower depth using said casing cutter tool (20). The pulling out operation may involve several thousand feet as shown in the illustrations A3, B3, C3 to A4, B4, C4.(In case said spear tool (10) was not inserted in the toolstring initially, such as in Fig. A1 to A5, after the cutting, pull up and insert said spear tool (10) into the toolstring as illustrated in Fig. B6 and A6..) (In case the spear tool (10) already was inserted in the toolstring, such as in Figs. A1 to A5, it is not necessary to pull up and insert the spear tool (10), and then the steps of Fig. A6 and A7 have been indicated by “X” as not required, and we may proceed to the test pulling of Fig. A8.)Test pull the severed-off casing section using said spear tool (10) as illustrated in Fig. A8, B8, and C8.If the test pulling is successful, pull up and remove the spear tool (10), the cutter tool (20) and the wash tool (40).(If the test pulling is not successful, if using a spear plug (10’) as in Fig. C8, pressure up on the drill pipe string to add piston pressure force from below on the severed-off casing section, and try also to wash out the annulus via the cut. If still not successful in test pulling, pull up and reinsert the cutter tool and make a shallower cut and repeat the test pulling, until successful test pull.)Then reinsert spear tool (10), run it into the well and engage with the severed-off casing section, please see Figs. A10, B10, and C10, and pull said severed casing out of hole, as illustrated in Fig. A11, B11, and C11.PerforatingIn an embodiment of the invention, after running into hole and placing the perforation gun (50) at the predetermined perforation depth,- perforate the casing by landing a first ball (52B) in said first ball seat (52), pressure up to trigger firing head (53) to fire the guns (50) and perforate the casing, please see Figs. 1A, 1B, and 1C, and- let an automatic gun release (54) drop the used perforation guns (50).Washing P19948NO00 to be filed in Norway 19.03.2021In an embodiment of the invention, wash the perforated casing section annulus by- landing a second ball (42B) in said second ball seat (42), please see Fig. A2, B2, C2,- circulate wash fluid into said perforated casing annulus while running said wash tool (40) along said perforated casing section and circulating out debris from the perforated casing annulus.- After having washed out the casing annulus, place said wash tool (40) in blank casing,- shear out the second ball seat (42) and circulate debris in said toolstring annulus out of hole.Due to the fact that the second ball seat has been sheared out, we may pump wash fluid through the wash tool axially, and back up through the bypass line (40) across the swab cups, and thus circulate out the debris.CementingIn an embodiment of the 11. The method for pulling a casing of claim 7 - 10 further comprising- circulate in cement into annulus by- land a third ball in said third ball seat (43) below said wash tool (40). This will close the main bore below the swab cups.Preferably, one should test the integrity of the swab cups in a blank casing section before continuing.- While running said wash tool (40) along said perforated casing section, circulate in spacer/primer fluid into said perforated, washed casing annulus.- Run said wash tool (10) along said perforated casing annulus, from bottom to top, and circulate cement into said primed perforated casing annulus while pulling up, and- while pulling up, also cementing further into the casing bore using wash tool bypass (44)- pull up to above the top of cement, and shear said third ball seat (43), please see Figs. A3, B3, C3, and circulate out remaining cement from the toolstring annulus, i.e. within the casing above the cement plug formed.Wait on cementIn an embodiment of the invention, one shall now wait on cement, i.e. until the cement plug has set and hardened sufficiently to conduct a pressure test, increase the pressure in the casing to pressure test the formed cement plug. We are now at the stage of Fig. A3, B3, and C3, and before the cutting in Fig. A4, B4, C4. If the pressure test, which tests sealing from above, is OK, we are sure that the plug, which is of more than 250’ length in the example, has sealed from rock to rock across and along the perforated section, and forms one permanent fluid barrier.Cut casingIn an embodiment of the invention, the method further comprises to cut the casing by - pulling up the toolstring with the cutter tool (20) to the predetermined cut depth, - land a fourth ball (22B) in said fourth ball seat (22) in said cutter tool (20), - pressure up in the drill pipe string to extend the knives (22) of the cutter tool (20), - rotate the drill pipe string with the cutter tool (20) and make a circumferential cut in the casing at the predetermined cut depth, please see Figs. A4, B4, and C4, while - the swivel (30) allows the wash tool (40) below to be non-rotating, P19948NO00 to be filed in Norway 19.03.2021- release the pressure in the drill pipe string (22) and deactivate the cutter tool’s (20) knives (24).Now the cut-off casing section, the severed casing section, should be tested for whether it is possible to pull out and lay out of hole.Test pullAccording to an embodiment of the invention the method further comprises to test pull said severed-off casing section by- pull up said cutter tool (20) to well clear above said cut,- activate and set slips of said spear tool (10) in the severed-off casing section, please see Fig. A8, B8, and C8.- test pull said severed-off casing section to determine whether it is free.There are two possible situations before the test pull can take place:- either we initially have a spear tool (10) in the toolstring as in Fig. A1 to A 5 whereby, with which we may proceed directly to the situation in Fig. A8, (we have indicated that the actions of the crossed-out Fig. A6 and A7 wherein we otherwise would have to insert a spear tool (10) and running it into hole is not required), - or we have no spear tool (10) initially in the toolstring and have to to insert a spear tool (10) and running it into hole in order to conduct a test pulling, please see Figs. B6 and B7, and C6 and C7.If no spear tool initiallyThus, in an embodiment of the invention, in case said spear tool (10, 10’) was not inserted in the toolstring initially, after the cutting, pull up and insert said spear tool (10, 10’) into the toolstring above the cutter tool (20), please see Fig. B6 and C6, and run in said spear tool (10, 10’) into the well and engage with said severed-off casing section, please see Fig. B7, B8, and C7, C8, and test pull the severed-off casing section using said spear tool (10, 10’). Please see Fig. B8 and C8.Test pull not yet OKIn case the test pull is not OK and the severed-off casing section is stuck, we still have the cutter tool in the well, and may repeat the cutting process with cutting higher up and test pulling until free.Test pull OKIn case the test pull is OK, we may now pull out the severed-off casing section. But at the surface the drill pipe string with the spear tool (10, 10’), the cutter tool (20), the swivel (30) and the wash tool (40) will usually be in the way of the process of removing the severed-off casing section and lay it out; in an embodiment of the invention we have to remove the spear tool (10, 10’), the cutter tool (20), the swivel (30) and the wash tool (40) before pulling the severed-off casing section out of hole.In the embodiment we pull out said severed-out casing section by- pulling up and laying out said spear tool (10, 10’), said casing cutter tool (20), said swivel (30) and said wash tool (40), please see Fig. A9, B9, and C9. Now the casing cutter tool and swivel and wash tool will not interfere with the casing when laying casing out, - reinsert said spear tool (10, 10’), please see Fig. A10, B10, and C10, and- run in hole said spear tool (10) to engage and hold said severed-off casing section, - pull out of hole said severed-off casing section, P19948NO00 to be filed in Norway 19.03.2021- release and remove said insert spear tool (10),- lay out said severed off casing section.Please see Fig. A11, B11, and C11.In an embodiment of the invention, if the top of the casing is a casing hanger, engaging said spear tool (10, 10’) in the casing hanger , please see Fig. A8, B8, C8, of said severedoff casing, before pulling it out.This concludes the embodiments of the method and the severed-off casing section has been laid out of the well.Appendix: Example of a planned operation on a well.IntroThe invention is lined out with details of the below planned operation on a well. The present invention relates to a plug and abandon operation with a pulling out of a casing from the well. The Perforate, Wash and Cementing operation utilises the applicant's so-called Barricade system, a single trip system to perforate a casing wall, wash the casing annulus, and circulate in cement to the annulus to establish a cement barrier across a geological formation, here the Shetland Group formation.Some of the essential tools used in the operation according to the inveniton are:9-5/8” "Stronghold Barricade System" - an annulus wash tool (40) also used for annulus cementing9-5/8” "SAMURAI MF Cutter" - a casing cutter tool (20)9-5/8” "Spearhead Plug" - a spear and plug tool which is enabled to hang off drill pipe string below.According to regulations for abandoning a petroleum well, a dual barrier is required, therefore 254ft of perforations will be made and a 600ft cased hole cement plug will be placed within the 9-5/8” casing.Pump and pull rates are based on 15ft stroke of the HWO Unit.BHR Height used has been 27.5ft.● Shetland formation depths: 6,831ft – 9,436ft BHR MD at 31° inclination.● Top of completion packer is at 8,700ft BHR MD. P19948NO00 to be filed in Norway 19.03.2021Planned perforation depth will be 8,027ft – 8,281ft BHR MD (254ft) with a further 346ft internal cased hole plug covering 7,681ft – 8,027ft MD to ensure the combined plug (600ft) covers the Shetland Group formation.A wireline set plug may be set at 8,578ft BHR to allow a sump to drop the TCP BHA into. Drill string to be used will be 5” NC50 drill pipe to surface.Pre-Job PlanningAs part of the pre-job planning at a minimum the following should be carried out to ensure flawless execution.Fluids to be sent out pre-mixed where possible.● Ensure all drill pipe is drifted to minimum 2-1/4” to ensure no restrictions for the 1.75” wash tool (40)'s ball.● Confirm ability to pump at a minimum 8.7bbl/min using Altus Pump and surface setup. ● Confirm max allowable rotation of the unit for use during bottoms up.● Ensure suitable pit plan is in place for cementing/spacer operations.● Confirm spacer has been sent out pre-mixed.● Ensure cementing volumes and all fluid weights are confirmed with cementer to ensure suitable chemicals are available and can be prepared and pumped efficiently.Planned Wash fluid is 10.4ppgPlanned Spacer fluid is 10.4ppgPlanned cement fluid is 16ppg● Ensure permits are prepared and plan to be in place for shifts when TCP operations may occur.● Ensure Archer crew are aware of the barrier policy on the Brent Charlie.● Firing head and cementing calculations to be finalised offshore based on latest information.● Ensure surface lines are tested to 4,500psi for Archer TCP operations.● Plan to ensure spacer and cementing operations do not fall across shift change. ● Connections to be made as efficiently as possible, if shift change occurs over washing procedure remain static and continue to circulate – do not stay static without circulation.● Check and confirm pipe tally and space-out.● Check and confirm availability of 5” drill pipe on the Brent Charlie to utilise above the wash tool (40).● Confirm swivel assembly to be used during washing and for Pump Pull operations ● If using King Swivel, ensure a suitable plan for handling the swivel/joint has been assessed.● Ensure ATEX Zone 1 Tablet is charged for washing operations.● Confirm if new monitoring system on the HWO unit can be used to record washing data. Embodiments of the inventionBelow is described embodiments of the invention. The invention is in one aspect a method. The invention is, in another aspect, a toolstring arranged for conducting the method. We describe the entire operation beginning with preparations and ending with the situation wherein all sections of the severed-off casing section has been laid-out on deck. The below description of embodiments of the invention is based on the inventor's "Archer Oiltools' Shell BC07 Operation Procedure" for conducting the entire perforate-wash-cement operation for plugging the well in the Shetland Formation before cutting the casing at a shallower depth and pulling out the severed-off casing section.The method may be employed for other wells in the same Shetland Formation, of course adapted to the local relevant depths, but may also be emoployed in other similar wells wherein the well shall be subject to casing perforation, washing and cementing before cutting the casing at a shallower depth and pulling out the casing. During the procedure the bottomhole assembly generally comprises a casing perforation gun (which is dropped automatically after perforating), a casing annulus wash and cementing tool, a casing cutter tool, and a spear tool, possibly a combined spear and plug tool is applied, although the spear and plug tool is in some embodiments inserted into the toolstring after the cutter tool has been employed.Operation Procedure with commentsBelow is described the exemplary operation procedure in minute detail.RIH Run in Hole1. Hold TBT. Ensure everyone is aware of the upcoming operation. Ensure everyone is aware of the restrictions/dangers of handling explosives.2. Make a PA announcement and barrier off relevant areas prior to rig up Tubing conveyed perforation (TCP) guns (50).3. M/U tubing conveyed perforation (TCP) BHA as per Archer engineer instructions.Install TCP safety clamp to tubing conveyed perforation (TCP) guns (50) and lift up using 7-5/8” single joint elevators on the WellGear winch and set in the slips in the rotary. Safety clamp remains on until being removed before running through the rotary.Note: Auto-slips can be used for running the Tubing conveyed perforation (TCP) guns (50) – this eliminates the use of hand slips.Note: Additional crossovers have been sent out to allow make up to 1 x joint to be able to lower the complete gun string to the lower deck to aid space out.Note: Confirm ability to utilise winch. Gun string length has been reduced, new winch has better lifting capability. 4. Utilising the required crossovers and a joint of drillpipe, lower the top of the gun string to the lower window for better space-out.5. P/U the wash tool (40) System assembly using the WellGear winch, secure bottom of BHA when moving towards the rotary. Check functionality of the swivel, rotation by hand.6. M/U tubing conveyed perforation (TCP) gun (50) firing head system to the bottom of the wash tool (40) assembly.Note: Only Archer personnel to be on the floor when making up the Pressure Activated Firing Head to the tubing conveyed perforation (TCP) gun (50) string. Note: an 11ft spacer has been loaded out therefore firing head needs to be made up with the top of spacer gun at lower window slips.7. Grab the upper pup joint of the Wash tool (40) System in the upper clamp and M/U wash tool (40) System to tubing conveyed perforation (TCP) (50) string using chain tongs.Note: Ensure that the wash tool (40) system is supported so as to not resting on the swab cups.8. Lower the wash tool (40) system through rotary and suspend in slips● Run slowly through BOP / WH or any other restrictions. 9. P/U Archer CUTTER TOOL (20) Multifunction Cutter BHA and remove protector (if applicable)10. Confirm knife location downhole to spaceout correctly for avoiding casing couplings 11. M/U cutter tool (20) to the wash tool's (40) Pup Joint12. RIH to tag the pre-set wireline (or "E-line") bridge plug and pull back to space out in order to allow about 324' sump/rathole for dropping the gun)● Plan to break circulation every 1,500ft, maximum 700psi● Max tag should be 5klbs● Max RIH speed limited to 10s per 15ft stroke.● Run slowly through BOP / WH or any other restrictions.13. M/U topside swivel assembly and line up to pump down the string, slowly break circulation to confirm open flow path through the string.● Maximum pump pressure limited to 700psi● TCP engineer to be on the floor when circulatingActivate tubing conveyed perforation (TCP) guns (50)14. Break out swivel assembly and insert 1” steel ball, the first ball (52B) for activating Tubing conveyed perforation (TCP) guns (50). Allow to fall while making up swivel assembly. The first ball (52B) will eventually land in ball seat (52) and prepare for pressure triggering the firing head of the perforation guns (50).15. Test surface lines to 4,500psi.Note: Ensure the string is isolated from this pressure as test pressure will activate Tubing conveyed perforation (TCP) guns (50).16. Space out to ensure that the perforation guns (50) are on depth.17. Hold TBT prior to line test/ tubing conveyed perforation (TCP) guns (50) activation Note: Ensure all barriers are in place, make PA announcement to ensure rig personnel are made aware explosives are about to be activated.Note: Discuss best way of dealing with gun gas, or gas from the annulus.18. Close annular bag and rig up shot detection system.Note: Shot detection system is not Ex rated and needs a permit.19. Pressure up the drill string to 2,000 – 2,500psi to activate tubing conveyed perforation (TCP) gun (50) firing head.Note: Activation pressure to be confirmed offshore. ● The tubing conveyed perforation (TCP) gun (50) string will disconnect on activation of the firing head.● Circulation is regained through the string after the automatic gun release (AGR) has dropped the tubing conveyed perforation (TCP) guns (50).20. Carry out 15min flow check.Note: Be aware of any gun gas to surface.21. Open annular bag.22. Circulate the well over to 10.4ppg washing fluid.Note: Be aware of any gun gas to surface.Note: Be aware and prepared for any gas to surface.Washing Sequence23. Check if rig monitoring system for recording flow rate and pump pressure is running.24. Carry out circulation “fingerprint” and record below.25. Stop pumping and break out swivel and insert the second ball (42B), which is a 1.375” OD Steel Ball.26. M/U swivel.27. Circulate the second ball (42B), the 1.375” ball, to the second ball seat (42) below the wash tool at maximum 1bbl/min. Now the wash tool (40) main bore is closed and the swab cups may be pressure tested against blank casing.Note: Max running speed across perforations is 18s per 15ft stroke. 28. P/U into blank casing and confirm swab cup integrity to 1,000psi.29. Hold 300psi on the string and slowly RIH the wash tool (40) to locate top of perforations indicated by pressure bleed off. We may now assume that the fluid enters into the perforations.30. Continue to RIH a further 2ft to place the wash tool (40) swab cups in perforations.31. Now we start washing. Start pumping to circulate out to the annulus between the wash tool (40) swab cups and increase rate to a maximum loss free rate aiming for a minimum 8.7bbl/min aiming for 12bbl/min.● Maximum pump rate for 9-5/8” Wash tool (40) is 14bbl/min / 588gpm.● Maximum pressure allowed is 75% of 1.375” ball seat shear rating, 2,250psi. ● A loss free rate is crucial to ensure we have full control of the fluids and lifting debris to surface. This also ensures we have a stable well for when we carry out cementing operations.32. Move the wash tool (40) and wash downwardly: Once stable rate has been achieved wash downwards at 1ft/min monitoring for blank sections from TCP BHA. Ensure connections are made quickly and efficiently.Note: Archer engineer to record parameters in excel sheet on Archer Tablet.Note: Archer TCP engineer to provide blank section sheet.Note: Monitor debris returns over the shale shakers.Note: Reduce the pumping rate across TCP blank sections.Note: The wash tool (40) of the BHA is built to Option 2 with 1.76ft between internal cups to ensure blank casing sections are straddled.33. At bottom of perforations continue to pump a string volume while stationary.34. Switch off pumps and - pull up to top of perforations and repeat the wash down pass while monitoring for a decrease in washing pressure. We now reach the bottom perforations. The washing procedure is now finished and we prepare for primer and cementing of the washed-out casing annulus. But first we must circulate out the washed-out debris from the tool annulus. 35. RIH the wash tool (40) into blank casing below perforated zone and verify wash tool (40) swab cups pressure integrity to 1,000psi and continue to pressure up to 3,000psi shearing out the second ball seat (42) 1.375” ball seat and regain circulation through the bottom of the wash tool (40).Note: If long delays due to weather are expected discuss with town whether shearing the second ball seat (42) with the second ball (42B) 1.375” ball is correct option. Note: We are now circulating through the bottom of the wash tool (40) and up through the concentric bypass (44) (bypassing the swab cups and wash section) of the wash tool (40) and up the DP annulus in the casing, also called the "DP x casing annulus".36. In order to circulate out the washed-out debris, circulate min 1 x B/U at max allowable rate rotating the string above the swivel (40) above the wash tool (40) at max allowable rpm continuing to monitor debris returns over shakers. The wash tool (40) is not rotated.Note: Max allowable rpm on the rotary unit is 50 – 80RPM.Note: Confirm maximum RPM with WellGear.37. P/U to straddle bottom of perforations with the wash tool (40) swab cups and drop and circulate a third ball (43B) , a 1.75” ball to the third ball seat (43) which is arranged below the wash tool (40), at maximum 1bbl/min. This third ball (43B), when landed, closes the central bore of the wash tool (40) to re-enable circulation out to the perforated casing annulus.38. RIH to blank casing and verify integrity to 1,000psi to verify Wash tool (40) integrity.When OK, spacer circulation may commence.Pump & Pull Spacer fluid39. Hold TBT. Ensure all personnel are aware of roles and responsibilities; ensure communication between Derrickman/pumpman for transferring fluids from pits to the cement unit are clear.Note: Ensure radios are working correctly40. Displace full string to contain spacer. Note: Ensure volumes in/out are confirmed when pumping. Previous lesson learned has seen pumps jacking off showing incorrect volumes pumped.41. Carry out the pump and pull across perforations as per the displacement plan above.Pumping at 3bbl/min and pulling at 1min per 15ft stroke.Note: Due to spacer and wellbore fluid being same weight, closing of the annular bag on the string at connections can be eliminated as no U-tubing is expected.Note: Optional for new crews is to practice closing the annular bag during cementing is to prevent/reduce u-tubing of cement out of the string when making/break connections.Note: This can and should be used as preparation for carrying out Pump & Pull with cement if there are several new people involved in the operation. Everyone should be fully aware of what is required, if in doubt STOP.Pump & Pull Cement42. Hold TBT for cementing operations. Have a review to capture any lessons learned or improvements from the preceding spacer section. Ensure all communications are clear. Discuss the Archer displacement plan.43. RIH to straddle the bottom of perforations.Note: Ensure Cementer is aware of the plan and does not start to fill the tanks while displacing down the string.44. Pump the following volumes down the string as per displacement plan of the appendix below.● 97bbl Cement slurry● 13bbl Spacer● 43bbl of wash fluidThis will displace 10bbl of cement out of the wash tool (40) while stationary prior to starting Pump Pull operations. Cement will be circulated into the perforated casing annulus and rise above the upper swab cups and back into the toolstring annulus and the upper bypass (44) port. Pulling up while pumping will now also guide cement down through the bypass and cement the main bore of the casing below the lower bypass port.45. Start picking up to carry out Pump and Pull operations as per cement calculation parameters. Pumping at 3bbl/min and pulling at 1min per 15ft stroke.Note: Monitor maximum volume pumped allowed as per displacement plan.46. At the top of the perforations continue to P/U into blank casing and shear out the third ball seat (43) with the third ball (43B), the 1.75” ball seat pinned to 3,000psi.47. Continue to pump cement as a balanced plug as per displacement plan for the remaining internal cement plug in the main bore. Pumping at 1bpm.TTOC at approximately 7,681ft.48. POOH (Pull up) until clear above worst-case top of cement TOC at 7,112ft.49. Carry out minimum 1.2 x string volume B/U circulation at minimum 8.7bbl/min.Note: If a sponge ball is to be pumped recommended to only pump 1 sponge ball as pumping 2 could lead to the tool being partially plugged.The toolstring should now be free of cement and spacer fluid.50. POOH, i.e. pull up the toolstring and position the cutter tool (20) knives at cutting depth 3,227ft where the cut shall be made.51. Wait on cement WOC and pressure test the formed cement plug formed with the above perforation, washing, and cementing procedure, the so-called "Shetland plug".Note: Shell to advise timings and parameters52. Drop a fourth ball (22B), a 2-1/2” activation ball for a ball seat (22) of a flow controller valve of the CUTTER TOOL (20) and record parameters without pumps53. Chase the activation ball (22B) to land in the seat (22) of the cutter tool (20) with maximum 1.5bpm 54. Watch for pressure build up to indicate that the fourth ball (22B) has landed in seat (22). Increase pressure to shear a pin which activates the longitudinal movement of a piston and piston rod controlled by a flow controller, activating the knife assembly of the cutter tool (20), and watch for pressure dropNote: If the initial shear is not observed when the maximum expected shear pressure (quoted pressure 25%) has been reached, it is recommended to adopt a staged increase in the application of pressure in order to obtain this shear.Note: The following procedure should be followed if this occursNote: Pressure up to 30% above shear value and hold for one minute.Note: If no shear observed, bleed off and pressure up to 40% psi and hold for one minute. Repeat this step a maximum of 3 times.Note: If after applying 40% 3 times no shear has been observed, bleed off and pressure right up until shear is obtained. This would only be done after consultation with Archer Representative. Maximum pressure 5000 psi55. Record flow parameters56. Stop pumps. Increase flow until torque increase is observed57. Increase pressure to achieve a cutting pressure drop of 870-1,160psi in 2mins until stable pressure is witnessedNote: If pressure and flow rate deviated from table below, pressure should be used as reference.58. USing the cutter tool (20), cut the casing at 3,227ft BHR MD according to Archer rep.An increase in torque may be observed during the cutting process. Subject to centralisation, the torque may become erratic as the cut proceeds.Note: Typical time to cut can be 2-5 minutes. Cutting time is calculated from when cutting pressure is reached. Variations in cutting time are not unusual.Note: If pressure and flow rate deviated from table above, pressure should be used as reference.Note: When pressure drop is observed, re-increase flow rate back to cutting pressure and continue to cut for 2mins to ensure clean cut59. When the cutter tool's (20) knife arms reach their pre-set diameter a pressure drop, due to the end position of the cutter tool's flow regulator, will be observed and the pre-determined knife opening is reached. Immediately increase pump rate to chase the required cutting pressure. A reduction in torque is expected.Note: Cutting a casing which is in compression can reduce the visibility of the reduction in torque and surface pressure drop.60. Maintain cutting pressure and continue cutting for a short duration (2 min). The knife arms will continue to the maximum knife sweep. To ensure a clean cut.61. Stop circulation, bleed of pressure and stop rotation.Note: Bleed off pressure thru the standpipe to prevent hydraulic locking62. P/U pick up string weight and POOH to bit depth 2,973ft BHR MD, which is 254' above the cut made at 3,227'.Note: Knives are now retracted into the pockets.Note: Do not seat knifes inside the cut as it may damage the hinge pin holes.Note: Due to potential washout of the nozzle assembly, cutter tool (20) shall not be used for excessive circulation. If the spear tool (10) was not inserted in the original toolstring, now the spear tool (10) shall be inserted into the toolstring. The reason for not having inserted the spear tool (10) before now is twofold: Firstly, if the spear tool (10) is in the embodiment of a SPEARHEAD spear plug tool (10') it has drag blocks and thus cannot rotate with the cutter tool. Secondly, the activation ball , the fourth ball (22) for the cutter tool (20) is larger than the bore of the SPEARHEAD spear plug tool (10'). 63. P/U the spear tool (10) assembly and remove the Safety Clamp from the spear tool (10) Running Tool. In case of using a spear plug tool (10'), Make sure the ball valve of the spear plug tool (10') is open64. M/U the spear tool (10) assembly to the drill pipe set in the slips65. Remove inner bushing and lower the spear tool (10) through the rotary66. M/U to NC50 drill pipe and RIH to engage the spear tool (10) in the casing hanger of the severed-off casing section. The casing hanger is at a depth xxxxxxxxx Note: While running into hole, run the spear tool (10) slowly through BOP/WH and any other restrictionsNote: Do not set the slips on the DP when spear tool (10) is in BOP/WH.67. Record up/down weights and DP stretch68. Start circulating and condition mud in order to clean the spear tool (10) and the internal casing wall of the setting area. In case of using a spear plug tool (10') , start circulating and condition mud in order to clean the lips, drag blocks of the spear plug tool (10') and the internal casing wall of the setting area. Depending on the well condition, circulate for 10 min. with maximum rate.Note: Full attention paid to pump pressure and weights during entire operation Note: Reciprocate the spear tool (10), while circulating, 6 ft. above and below, either side of the setting area. Note that reciprocation of pipe while circulating will increase amount of fluid bypassing the spear tool (10) and circulation rate may have to be decreasedNote: Stop circulation before proceeding with setting sequence.Note: Confirm recorded weights after circulation69. Make sure to space out in a manner so that you have some room to work with during setting, ideally 30ft. above RKB.Note: should be to place mid-joint of single across BOP’s to prevent connection being immediately below or at blind shear rams of the BOP when the spear tool (10) is set. 70. Move DP down to 6ft above desired setting depth and pick up to neutral weight. 71. Activate the slips of the spear tool (10). In case of using a spear plug tool (10'), Establish right hand RH rotation at 15-20RPM. Confirm stationary wind-up torque by rotating the drill pipe string slowly until break-over torque of the spear tool (10) is reached & weight is confirmed, minimum 10 turns. This will activate the slips and the packer of the spear plug tool (10'). Record number of turn to achieve free rotation torque (FRT), and weight(FRW):72. Set the slips of the spear tool (10). In case of using a spear plug tool (10'),move the string down at approximately 1ft/s in order to engage and set the slips of the spear plug tool (10'). When the spear plug tool (10') starts to take weight, stop rotation, release torque and set down minimum 44klbs below slack off weight (SOW), holding weight 2mins73. Pick up, in order to have 22klbs. tension on the spear tool (10), compared to Pick up weight (PUW)74. Release torque in the string and verify that the spear tool (10) is set according to Archer rep. Now the spear tool (10) is ready to pull the casing.75. Pull the severed-off casing section according to Archer repNote: Pull in steps, each step until stable weight.Note: Max hook load while pulling: 701,120lbs Block weightNote: Evaluate to circulate while pulling76. If the severed-off casing section is not free, follow the below steps: Step 1: Work the toolstring up and downStep 2: Apply fluid pressure while pulling, max 1,885psi bar in 290psi steps (reduce max pull to 649klbs block weight when applying 1,885psi, because the fluid pressure will create extra tension in DP)Step 3: Keep pressure / tension for a while to allow for possible movement of the severed-off casing section, max 30 minutes. If still no free severed - off casing section, we still have the cutter tool (20) available in the well but cannot cut without laying out the spear tool (10). See below.77. If the severed-off casing section is free and possible to move, release the spear tool (10), because we will now lay out the cutter tool (20) and the wash tool (40) before pulling out the severed-off casing:78. Slack off to have 5klbs above free rotation weight (FRW).79. Release the spear tool (10). In case of using a spear plug tool (10'), still with 5klbs above the free rotation weight (FRW), start RH rotation at 15-20 RPM, in order to release spear plug tool (10').80. In case of using a spear plug tool (10'), when spear plug tool (10) is free, pull the string slowly as you rotate another 10 turns. Then stop rotation gently as you continue pulling the string another 10-12 ft.81. In case of using a spear plug tool (10'),If no indication that spear plug tool (10) has released after 20 turns, increase over pull in steps towards pick up weight. Once spear plug tool (10) releases pull the string slowly as you rotate another 10 turns. Then stop rotation gently as you continue pulling the string another 10-12 ft.NOTE: Make sure that while operating spear tool (10), the TD must at all times be positioned so that spear tool (10) can be released and DP made up/broken with the Iron Rough Neck82. Stop pulling and wait 10 minutes to allow elements to fully retract.83. If possible, run spear tool (10) in-hole to below setting depth, to ensure that spear tool (10) is retrieved and free.84. POOH and lay out the spear tool (10) assembly. We shall now get rid of the cutter tool and wash tool before pulling the severed-off casing section.85. POOH and lay out the Archer CUTTER TOOL (20) and wash tool (40). The reason for having kept the cutter tool (20) in the workstring until now is due to the fact that if the severed-off casing section remained stuck and impossible to poll, we could now make a new cut and try to pull the new, shorter severed-off casing section in order to proceed. 86. P/U the spear tool (10) assembly and M/U to NC50 drill pipe. RIH to engage the casing hanger of the severed-off casing section. The casing hanger is at a depth of xxxxxxxxxNote: Run the spear tool (10) slowly through BOP/WH and any other restrictions Note: Do not set the slips on the DP when spear tool (10) is in BOP/WH.87. Repeat steps 67-76 for setting the spear tool (10) in the severed-off casing section, now without the cutter tool (20) and wash tool (40), and to determine that the severedoff casing section is free.88. Apply overpull to lift casing xxxxxx and break circulation to wash old mud from behind the casing89. POOH Pull the casing hanger out of hole and lay out the casing hanger90. Release the spear tool (10) as per steps 78-82. L/O Spear tool (10) assembly 91. L/O lay out the severed-off casing section using casing handling equipment.The severed-off casing has now been removed from the well, subsequent to the well having been plugged. Appendix: Fluid Displacement PlanPumping speeds slowed down to compensate for time to move jack HWU’s Fastest pulling speed with weight of string is 1min per 15ft stroke which includes jack movement timeAll Depths reference BHR – Basket Handrail Depth which is ODES 27.5ft1. With wash tool (40) at the bottom of the perforated section. Circulation ports 1ft above bottom shot at 8,280ft. Pump 153bbl of Spacer @ 7.5 BPM using the Altus pump.● This will displace full string to spacer and pump 10 bbls out of the wash tool (40) . ● This will fill lines with Spacer● Reduce pump rate to 3bpm on final 10bbls in preparation for pump and pull.2. Begin pump and pull through perforated section Pumping at 3bpm and pulling at 60s per 15ft stroke (HWU’s fastest pulling speed jack movement time = 1min per 15ft stroke)● Monitor return volumes for volume control● When tool reaches top perforation, Circulation ports 1ft below top perf @ 8,028ft (Total volume of Spacer pumped should be 205bbl (52bbl pumped into perforations).3. After Spacer pump and pull is complete RIH to position circulation ports 1ft above bottom shot at 8,280ft.4. Pressure test surface lines to 3,500psi from cement unit to HWU.5. Pump 97bbl of cement at 4bpm.● Set cement unit pressure limiter to 1,500psi (ball seat shear pressure 3,000psi).6. Pump 13bbl of spacer @ 3 bpm.● In the string there will be 33bbl spacer+ 97bbl cement 10bbl spacer 3bbl spacer/cement line Volume (Total Volume 143bbl)7. Switch line up to pump from Altus Unit● Make sure flow meter reading zero8. With wash tool (40) stationary, pump 43bbl of Jetting Fluid @ 3bpm● 10bbl of cement will be displaced out of the wash tool (40)Note: Monitor displacement closely from this point 9. Begin Pump and pull through perforated section displacing with Jetting Fluid Pumping @ 3bpm and pulling at 60s per 15ft stroke (HWU’s fastest pulling speed jack movement time = 1min per 15ft stroke)● When breaking connection close annular ram to prevent u-tubing● When tool reaches top perforation Circulation ports at 8,028ft. Total volume of Jetting fluid pumped by Altus Pump should be 95bbl● Maximum fluid to be pumped during first stage pump pull is 52bbl10. Continue picking up into blank casing above top shot and shear out ball seat at /-3,000psi 11. After shearing ball seat adjust pump rate to 1bpm and pump a further 20bbl of jetting fluid with the wash tool (40) in stationary position to place the balance plug.● Total Volume of Jetting Fluid pumped with Altus pump should be 115bbl.● Planned TOC at 7,681ft● Worst case TOC 7,112ft (Based on 11” Open hole and all excess above TTOC = 569ft) 12. POOH with ventilated string to place bottom of string @ 7,100ft.13. Circulate string Clean● Insert Qty 1 sponge ball● Max Circulation rate 10bpm.● Max rotation 60rpm.● Recommended to only pump 1 x sponge ball as 2 may risk blockage of the tool.14. Continue to cutting sequence Appendix: BHA Bottomhole assembly
Claims
P19948NO00 to be filed in Norway 19.03.2021CLAIMSTOOLSTRING CLAIM1. A well intervention toolstring comprising from top to bottom:- a drill pipe string,- a through bore spear (10), (a casing spear(10) or equivalent casing hanger running tool or spear plug with hang-off capacity,)- space-out drill pipe string,- a through bore cutter tool (20),- a swivel (30) below the cutter tool (20),- a swab cup wash tool (40) ,- a perforation gun (50).Ball seat in cutter tool2. The well intervention toolstring of claim 1,wherein the through bore cutter tool (20) has a fourth ball seat (22) arranged for receiving a fourth ball (22B) arranged for building up pressure in the cutter tool (20) in order to extend knives (24).Wash tool3. The well intervention toolstring of any of the preceding claims, wherein the swab cup wash tool (40) further has a bypass line (44) across the wash tool (40) swab cups (46),- said wash tool arranged for washing the perforated annulus,- said wash tool arranged for subsequently cementing the perforated casing annulus, cement passing back in through the perforations and passing through the bypass line (44) to cement the casing main bore.Ball seats in wash tool4. The well intervention toolstring of any of the preceding claims, further comprising- a second and third ball seat (42, 43) arranged for receiving a second and third ball (42B, 43B) below the swab cup wash tool (40).Ball seat in gun firing head5. The well intervention toolstring of any of the preceding claims, further comprising a first ball seat (52) in a firing head (52) and AGR (54) for the perforation gun (50).6. The well intervention toolstring of any of the preceding claims, wherein - the through bore spear (10) is a spear plug tool (10') which comprises a packer and further comprises a switchable ball valve having a bore > 2'' diameter.P19948NO00 to be filed in Norway 19.03.2021METHOD CLAIM7. A method for pulling a casing,comprising the steps of:- assembling the toolstring of any of claims 1 - 6,- run in hole and place the perforation gun (50) at a predetermined perforation depth,- perforate the casing using the perforation gun (50),- wash the perforated casing annulus using the swab cup wash tool (40), - circulate in cement into the washed casing annulus and the casing bore using the swab cup wash tool (40),- wait on cement and pressure test the cement plug so formed,- pull up and cut casing at a shallower depth using said casing cutter tool (20),- test pull the severed-off casing section using said spear tool (10), - If test pull successful, pull up and remove said spear tool (10), said cutter tool (20) and said wash tool (40),- reinsert said spear tool (10) and run in to engage the severed-off casing section, and pull said severed casing section out of hole .If no spear tool initially8. The method of claim 7,- in case said spear tool (10) was not inserted in the toolstring initially, after the cutting, pull up and insert said spear tool (10) into toolstring above said cutter tool (20) and test pull the severed-off casing section using said spear tool (10).Perforating9. The method for pulling a casing of claim 7 or 8,comprising the further steps of:- run in hole and place the perforation gun (50) at a predetermined perforation depth- perforate the casing by- land a first ball (52B) in said first ball seat (52), pressure up to perforate the casing- let the perforation gun (50) drop.Washing10. The method for pulling a casing of claim 7 - 9,- wash the perforated casing section annulus by- landing a second ball (42B) in said second ball seat (42), P19948NO00 to be filed in Norway 19.03.2021- circulate wash fluid into said perforated casing annulus while running said wash tool (40) along said perforated casing section and circulating out debris from the perforated casing annulus,- place said wash tool (40) in blank casing,- shear out the second ball seat (42) and circulate out debris out of hole.Cementing11. The method for pulling a casing of claim 7 - 10 further comprising- circulate in cement into annulus by- land a third ball in said third ball seat (43) below said wash tool (40) - while running said wash tool (40) along said perforated casing section, circulate spacer/primer fluid into said perforated, washed casing annulus- run said wash tool (10) along said perforated casing annulus and circulate cement into said primed perforated casing annulus while pulling up and- while pulling up, also cementing further into the casing bore using wash tool bypass (44)- pull up, shear said third ball seat (43), and circulate out remaining cement.Wait on cement12. The method for pulling a casing of claim 7 – 11, further comprising wait on cement and pressure test cement plug.Cut casing13. The method for pulling a casing of claim 7 – 12, further comprising- cut the casing by- pulling up the toolstring with the cutter tool (20) to a predetermined cut depth,- land a fourth ball (22B) in said fourth ball seat (22) in said cutter tool (20),- pressure up to extend the knives (24) of the cutter tool (20),- rotate the drill pipe string with the cutter tool (20) and make a circumferential cut in the casing at the predetermined cut depth, while - the swivel (30) allows the wash tool (40) below to be non-rotating, - release the pressure and deactivate the cutter tool’s (20) knives (24).Test pull14. The method for pulling a casing of claim 7 – 13,- test pull said severed-off casing section by- pull up said cutter tool (20) to well clear above said cutP19948NO00 to be filed in Norway 19.03.2021- activate and set slips of said spear tool (10) in the severed-off casing section- test pull said severed-off casing section to determine whether it is free.15. The method for pulling a casing of claim 14,- in case said spear tool (10, 10’) was not inserted in the toolstring initially, after the cutting,- pull up and insert said spear tool (10, 10’) into the toolstring above the cutter tool (20),- run in said spear tool (10, 10’) into the well and engage with said severed-off casing before test pulling said severed-off casing section.16. The method for pulling a casing of claims 7 – 15,- pull out said severed-out casing section by- pulling up and lay out said spear tool (10, 10’), said casing cutter tool (20), said swivel (30) and said wash tool (40),- insert said spear tool (10, 10’) and- run in hole said spear tool (10) to engage and hold said severed-off casing section,- pull out of hole said severed-off casing section,- release and remove said insert spear tool (10),- lay out said severed off casing section.17. The method of claim 16, wherein engaging said spear tool (10, 10’) in a casing hanger of said severed-off casing.
Drawings

Priority

No priority

Patent classes

IPC classesE21B 29/00E21B 33/13E21B 43/112CPC classesE21B 29/002E21B 29/005E21B 33/13E21B 43/112

Citations

WO 2020/256563 A1 (A1)WO 2015/115905 A1 (A1)WO 2015/105427 A2 (A2)WO 2021/040531 A1 (A1)US 2015/0275605 A1 (A1)NO 342549 B (B)

Applicants, owners and inventors

Owners
Archer Oiltools AS
Postboks 8037 4068 STAVANGER NO (STAVANGER Municipality, Rogaland county)Org. number: 968145843Inventors
Bjørn Tore Torvestad
Hordaveien 12 4020 STAVANGER NO (STAVANGER Municipality, Rogaland county)

Agent

BRYN AARFLOT AS
BRYN AARFLOT AS

Org. number: 979993269

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Stortingsgata 8 0161 OSLO NO (OSLO Municipality, Oslo county)
Org. number: 979993269
Reference: -

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