NO20200492A1

NO20200492A1 - Improved wireline cutting, pulling, and squeezing pipe recovery system

Info

Publication number: NO20200492A1
Application number: NO20200492A
Authority: NO
Inventors: Trond Skjeie
Original assignee: Archer Oiltools As
Priority date: 2020-04-23
Filing date: 2020-04-23
Publication date: 2021-10-25
Also published as: NO347304B1

Description

Introduction

The present invention is a petroleum well casing or tubing recovery system. More specifically, casing or tubing being pulled out of a well is flattened in a continuous process rather than being broken out into separate pipe stands. The resulting flattened casing belt may be wound up to a casing belt coil or cut into flat casing belt sections put in a basket or other container.

Problems of prior art

During an oil or gas well Permanent plug and abandonment or Slot Recovery, pipe (tubing or casing) has to be removed to facilitate for required barriers dictated by government regulations. Tubing are always recovered from wells.

Tubing may typically have dimensions 23/8 '' to 41/2 '' or up to 51/2 '' and are used in well completions in a casing pipe. Casing pipe extends from the surface to its intended depth. Casing pipe most often requiring to be pulled out is 95/8'' or 133/8''. Casing pipe sections or tubing sections are normally joined by threaded casing joints or tubing joints, respectively.

Traditionally this is done by the main rig, Derrick, breaking the casing into casing sections by removing one by one pipe section or stands of 2 or 3 pipe sections, by unscrewing or cutting the casing in to specific lengths. The lengths are determined by the handling capacity of the rig, usually into stands of 3 x 12 m casing pipe. This is a time consuming operation, due to several hundreds or thousand meter length of the pipe to be broken . Also the fact that each time a pipe stand length is recovered, the top drive will have to travel down to pick up the next pipe section. Rigs have to spend hundreds of hours doing such nonproductive work. Drilling a well is productive work.

The used casing or tubing pipe to be removed is being pulled by the hoisting mechanism of a derrick is in the background art and the hoisting is halted for each "stand" of 3 pipe sections and the stands are broken out into casing sections and stored in the pipe rack. Storing generally hollow, empty casing stands of Ø 95/8 (244 mm) and length 3 x 12 m and wall thickness about 10 mm, occupies a large, generally empty volume in the stored casing stands, which have no operational value but shall only be exported for steel recovery. The background art process is costly, slow, and time-savvy.

Brief Figure captions

The invention is illustrated in the attached drawing Figures, wherein

Fig.0 is a a rough illustration of a vertical section of a part of a well and a surface platform (marine or land). There is at least one casing (or tubing) (00) in the well, usually surrounded by a second, third, casing (01, 02, ... ). There is arranged a pulling mechanism (11) on the platform over the well, and arranged for pulling out a long length of the casing or tubing (00) from the well. A casing or tubing (00) such as a 95/8'' casing, which has been cut by a cutting tool and released from possible cement and arranged in an enveloping casing such as 133/8''. The cylindrical casing or tubing pipe (00) being pulled up out of the well in a more or less continuous manner is then according to the invention arranged for being run between two flattener rollers (10), also called "squeeze" rollers (10), also in a continuous manner, e.g. in a length of 100m to 500m, to form a flat belt (12) emerging in a generally continuous movement from the flattener rollers (10). In the left portion of the drawing, the casing / tubing (00) is held in a start position by the pipe pulling mechanism (11) and ready for engagement with the open flattener rollers (10). In the right portion of the drawing the flattener rollers (10) have been fully engaged with and flattening compressing the up coming casing / tubing pipe (00) which is pulled up in a continuous manner by the pulling mechanism (11).

In an embodiment of the invention the flattener rollers (10) are mounted pairwise on actuators (17) on an auxiliary rig frame (19) and arranged for initially engaging and exerting a squeezing, flattening force pair on the emerging pipe (00). In an embodiment the pulling mechanism (11), preferably pulling rollers (11), are mounted in a peripheral arrangement on actuators (18) arranged on the same rig frame (19) and arranged for engaging and exerting an axially pulling force on the pipe to be flattened. Alternative to pulling rollers (11) one may use a jacking mechanism (11') for continuously jacking out the casing or tubing (00). In an embodiment the pair of flattener rollers (10) carry the function of the axially pulling rollers (11), but it may be advantageous as seen from a safety point of view, to separate the function of pulling rollers (11) from the function of flattener rollers (10), in order to, among other, to preserve the axial pulling force capacity of the pipe junctions in their undeformed state when pulling, and then flattening the pipe junctions in a clean flattening operation.

Fig.1 is a vertical section corresponding to Fig.0. In an embodiment of the invention shown in Fig.1, the resulting flattened casing or tubing belt (12) is conveyed along a conveyor mechanism (30) to a coil drum (20) which winds up the flat belt (12) to a belt coil (14). This belt coil (14) is then exported as waste steel for smelting and re-use.

Fig.2 which is rendered together with Fig.1, is a steeply oblique view from point (A) of Fig.0 or Fig. 1, and shows in part perspective view the rollers of an underlying pipe pulling mechanism (11) axially feeding the up coming casing or tubing pipe (00) up to the above flattener rollers (10) which squeeze and flatten the cylindrical casing or tubing pipe (00) to an up coming flat belt (12) of flattened pipe.

Fig.3 is a vertical section corresponding to Fig.0 or Fig.1, wherein an embodiment of the invention is provided with a cutter apparatus (50) arranged for cutting the emerging flat belt (12) into belt sections (16). In a further embodiment of the invention the severed off belt sections (16) are carried by a robot arm (40) of a crane (42) for being put in a basket or container (44) for temporary storage near the rig and transport away from the well. This embodiment of the invention involving belt sectioning contributes to a very compact storage of the removed casing (00).

Fig.4 is drawn in a style similar to Figs.0, 1, and 3. In this embodiment, a wireline (72) is run into the well with a wireline casing cutter tool (75) for severing the casing (00) to be pulled. This embodiment may be used in combination with the embodiments of Fig.0, Fig.1, Fig.2, or Fig.3. In this embodiment , the flattener / squeeze drums (10) are retracted before lowering the wireline (72) conveyed casing cutter tool (75) into the well. The pulling mechanism (11) may be engaged exerting an axial pull when cutting. When the cutting of the casing (00) is done and the casing (00) is free to be pulled, the pulling mechanism (11) may start pulling, the flattener rollers (10) are engaged, e.g. as illustrated in Fig.0, and the pulling and flattening process commences. In this drawing the flat belt (12) is cut by the cutter apparatus / robot arm (40) to flat belt sections (16) and moved to the basket or container (44), but could as well be wound up to a coil (14).

Brief summary of the invention

The invention is defined in the attached set of claims. Embodiments of the invention are defined in the dependent claims.

There are significant advantages of the invention:

The invention relates to removal of a string of pipe used to produce oil and gas (tubing) or pipe used to support the borehole (casing) in oil or gas well. The Invention can be used to recover/remove casing or tubing pipe from a wellbore more efficiently than current methods used when performing permanent plug and abandonment or slot recovery of wellbores.

Usually, pipe recovery operations are conducted using a high day rate heavy intervention rig in a socalled in-line operation with the tubing conveyed casing or tubing removal procedures, normally involving bridge plug setting, perforation, washing and cementing operations. Moving this pipe recovery operation to an offline activity wherein the main drilling rig is not required, and reducing time spent to recover pipe, will have a significant impact on well cost, as the time spent on the heavy intervention rig for a particular well is reduced. Reducing the main rig activity in permanent plug and abandonment and / or slot recovery of wellbores will have a positive impact on oil or gas well cost.

The pipe (00) may according to the invention be pulled in a generally continuous process out of the well. With the present invention, the pipe (00) is not halted for each "stand" of two or three pipe sections and the stands broken out into casing sections and stored in the pipe rack, but continuously pulled up and flattened to a flat belt (12) of flattened steel casing or tubing (00). In an embodiment of the invention the pipe belt (12) is wound up on a coil drum to a coil (14). In another embodiment the pipe belt (12) is cut into belt sections (16) and stacked away in baskets or containers (44) for removal as steel waste. These embodiments both save much storage space in the pipe rack, and allows the resulting compact casing or tubing belt coil (14) or stack of belt sections (16) having far less volume than corresponding generally empty, stored casing or tubing stands, to be exported for steel recovery elsewhere. The process saves time and space.

The process of the present invention may be done on a free well slot while active well operations such as drilling, whipstock operations, cementing, etc. is conducted on another well slot. In this manner, the present invention saves time, too.

The embodiment of the invention involving wireline conveyed tools used for cutting the casing or tubing at the desired depth before pulling out of hole, saves much rig time. Further, the same wireline drum and equipment may be used after pulling the casing or tubing, to inspect the well and establish P&A barrier requirement before running the main rig for heavy intervention.

Embodiments of the invention

The invention . A petroleum well casing or tubing pipe (00) removal system

comprising

- a pipe pulling mechanism (11) arranged for pulling casing or tubing pipe (00) out of a well, and - a set of two or more flattener rollers (10) arranged for flattening said casing or tubing pipe (00) to a flat belt (12). Please see Fig.0.

in an embodiment of the invention the pulling mechanism comprises two or more drums (11) driven by a motor (M2) and supported in engaging actuators (18) which may be hydraulic actuators. In an embodiment the flattener "squeeze" rollers (10) are supported on axles (110) held by actuators (17), also those hydraulic. The actuators (18) and 17) may be mounted in an auxiliary rig frame (19) for being arranged on a well slot, independently from a drilling rig which may work on another well slot separately. A drilling rig usually has a derrick, a derrick crane, a drilling motor, a drilling swivel, a mud circulation system, and a cement injection system, all for operating on a drill pipe string with tools or piping run into the well. The costs for running such a heavy intervention rig may be about 200000 USD/day. The present invention's auxiliary rig frame does not need much of such components as the drilling rig does, and could cost as little as 20000 USD/day, and may remove the undesired or damaged old casing or tubing on a well in a slot, and prepare the well for subsequent plugging and abandonment and/ or sidetracking of the well by the heavy intervention rig moved to the same slot.

Preferably, in an embodiment of the invention, we pull the casing / tubing (00) in lengths of e.g.100 -500 metres.

Further, in an embodiment of the invention, the recovery system has a conveyor mechanism (30) arranged for conveying said pipe belt (12) away from said well. In an embodiment the conveyor mechanism (30) is arranged for conveying said flat belt (12) away form said wall and to a coil drum (20), said coil drum (20) arranged for winding up said flat belt (12) to a belt coil (14), necessarily with considerable force and torque required to wind the flat, thick steel belt (12) onto a relatively small diameter coil, e.g. with an initial radius of 1/2 metre or more, up to a final radius of about 4 - 10 metres. Advantageously, the pipe belt coil (14) may be transported away as steel recovery waste. A coil of e.g.4 m diameter and the with of the flat belt (12) of flattened casing is easily secured and lowered to a supply vessel and may be stacked on deck, please see Fig.1.

In a very simple embodiment of the invention, the flat belt (12) could, when being conveyed away from the well, be cut up into belt lengths (16) and stored in their flattened straight state in a basket (44) or container, for being transported away.

Pulled casing or tubing pipes are hollow pipes of equal diameter, which usually are stored broken up in lengths of three and three joints of 12 metres in a pipe stack outside the V-port of the derrick. Flattened straight pipe band sections (16) would constitute a far more compact storage space than their corresponding pipes. Cutting the flat belt (12) of flattened pipe is a possible embodiment we could in the present invention.

In an embodiment of the invention, the conveyor mechanism (30) is arranged for conveying said pipe belt (12) away form said wall and to a motorized coil drum (20), whereby the coil drum (20) is arranged for winding up said flat belt (12) of flattened pipe to a belt coil (14). Then the belt coil (14) could be transported away as steel recovery waste.

In other words, the invention is a method for petroleum well casing or tubing pipe recovery comprising the steps of:

- pulling casing or tubing pipe (00) out of a well by means of a pipe pulling mechanism (11), - flattening said casing or tubing pipe (00) to a flat pipe belt (12) using a set of two or more flattener rollers (10),

- conveying the resulting flat belt (12) away from the well.

In an embodiment of the invention we are using a conveyor mechanism (30) and we receive said pipe belt (12) on a coil drum (20), we wind up said flat belt (12) of flattened pipe (00) to a belt coil (14), and we transport away said belt coil (14) for steel waste recovery.

In one aspect, this would resemble coiled tubing, but with a significant difference: Coiled tubing is usually stored on large-radius drums so as for avoiding bending the coiled tubing to a radius smaller than the elastic limit of the tubing, in order to avoid irreversible deformation to the tubing. In the present invention, permanent, plastic deformation of the casing or tubing (00) is no problem because it shall be sent to steel recovery and not direct re-use as casing or tubing pipe. Thus the radius of the coil drum (20) may be as small as otherwise desired by the mechanical designer, without regard to the deformation of the belt (12) to a belt coil (14). Coiled tubing is useful steel for being fed into a well, wherein its properties must be maintained, and permanent deformation avoided. Used casing or tubing taken out of a well is waste, and may be handled in a way resulting in permanent deformation.

In an embodiment of the invention, said set of two or more squeeze flattener rollers (10) are arranged above said pulling mechanism (11). Please see Fig.0, Fig.1, Fig.2, and Fig.3.

In an embodiment of the invention the flattener rollers (10) also constitute said pulling mechanism (11), i.e. that the same rollers (10) which flatten the casing or tubing also pull the casing or tubing pipe (00) up from the well. This is shown in part of the drawing.

In another embodiment of the invention, also shown in the drawing, the set of two or more flattener rollers (10) are arranged separately and above said pulling mechanism (11). The pipe pulling mechanism may be a set of two or more gripping and pipe pulling rollers (11) or belts, with some rugged friction mechanism such as studs, for engaging the casing or tubing (00) before it reaches the deformation zone of the flattener rollers (10). The pulling rollers (11) would be arranged enveloping the casing or tubing (00). This would ensure that the casing or tubing (00) is evenly pulled and held over the well, even if the casing or tubing should partly or entirely disassemble in threaded casing joints usually separated by 12 metres for the casing example. Then the flattener rollers (10) have the separate role of flattening the casing or tubing pipe (00) with its threaded casing or tubing joints, to a flattened pipe belt of small thickness and large width of approximately 1/2 (2 pi R) = pi R = 1/2 Ø pi, or rougly 1.6 times the casing diameter. The casing or tubing joints will form thickened portions of the belt, but would otherwise be flattened, too. The flattened casing or tubing joints would be more or less randomly distributed around and inside the resulting belt coil (14).

In an embodiment of the invention the flattening rollers (10) are driven by a motor (M1, 15). The motor (M1, 15) or a separate motor (M2) may drive the pulling rollers (11). In an embodiment of the invention the flattener rollers (10) are provided with studs (101) for engaging the casing or tubing pipe (00), and so may the pulling rollers (11) have.

In an embodiment of the invention the flattener rollers (10) are arranged as a parallel pair with generally horizontal axes (110), i.e. the axes (110) are arranged transverse to the axis of the out coming casing or tubing pipe (00), please see Fig.2.

Some rough calculations

The casing (00) of e.g.95/8'' (Ø=244mm) will have a wall thickness of about 0.35'' - 0.4'' - 0.435'' (9, 10, 11 mm) typical for many Norwegian wells, so the flattening rollers (10) should flatten the generally cylindrical casing to a belt (12) with thickness of the double wall thickness, to 0.70'' - 0.80'' -0.87'' (18, 20, 22 mm) thickness and a width of ca.151/9'' (384 mmm). Please see the below table.

So the drum (20) would coil up about about 90 litres of steel for each length of 12 meter 95/8'' casing, in a coiled belt (14) of width less than 400 mm. Such a belt coil (14) on a drum (20) could store 500 metres of casing within a flat disc of height 400 mm and a diameter of less than 4 metres. The dimensions used above may of course be replaced with other commonly used casing or tubing dimensions according to the need of the well owner or operator.

In an embodiment of the invention, please see Fig.4, the method of the invention comprises the following steps conducted on a well from which a casing or tubing (00) shall be removed:

- run a wireline conveyed casing cutting tool (75) to a target depth and cut said casing or tubing (00), - pull said wireline conveyed casing cutting tool (75) out of hole,

- provide a frame (19) with a pipe pulling mechanism (11) and flattener rollers (10) on said well, and pull and flatten said casing (00) into a flat belt (12), which is removed according to either embodiment of the invention described above;

- run wireline tools such as cleaning or well logging tools including such wall thickness log, cement bonding log, for cleaning a wall of a previously surrounding casing and / or logging the well after removal of said casing (00).

According to an embodiment of the invention, there is arranged a wireline drum (71) with a wireline (72) arranged for lowering a wireline conveyed casing cutter tool (75) into the well for severing said long length of casing or tubing (00) to be recovered from the well, and arranged for removing said wireline conveyed casing cutter tool (75) from the well before engaging said flattener squeeze rollers (10) with said severed casing or tubing (00).

When preparing for the wireline operation before the pull and squeeze operation, the rollers (10) will be separated and out of squeezing engagement with the casing or tubing (00) when the wireline operations conduct one or more of the following:

- internal cleaning of the casing or tubing (00)

- perforation and annulus washing of the casing or tubing (00) in order to release the casing or tubing from being stuck in cement or debris,

- running the casing cutter tool (75)

- setting a bridge plug for preparing further operations such as cementing for plugging or installation of a whipstock for sidetracking.

In an embodiment of the invention the wireline conveyed casing cutter tool (75) is a motorized rotating knife tool severing the casing (00) at the desired depth.

Alternatively, instead of pulling said wireline conveyed casing cutting tool (75) out of hole, sacrify the casing cutting tool (75) and the wireline (72) in the well; which will save some time. This is particularly useful In an embodiment of the invention wherein the casing cutter tool (75) is an explosive tool.

Claims

1. A petroleum well casing or tubing pipe (00) recovery system comprising

- a pipe pulling mechanism (11) arranged for pulling casing or tubing pipe (00) out of a well, and - a set of two or more flattener rollers (10) arranged for flattening said casing or tubing pipe (00) to a flat belt (12).

2. The petroleum well casing or tubing pipe recovery system of claim 1, comprising

- a conveyor mechanism (30) arranged for conveying said flat belt (12) away form said wall and to a coil drum (20),

- said coil drum (20) arranged for winding up said flat belt (12) to a belt coil (14).

3. The petroleum well casing or tubing pipe recovery system of claim 1 or 2,

- wherein said squeeze rollers (10) also constitutes said pulling mechanism (11), i.e. that the same rollers (10) which flatten the casing or tubing also pull the casing or tubing pipe (00) up from the well.

4. The petroleum well casing or tubing pipe recovery system of claim 1 or 2,

- wherein said set of two or more flattener "squeeze" rollers (10) are arranged above said pulling mechanism (11).

5. The petroleum well casing or tubing pipe recovery system of any of the preceding claims, - wherein said flattener rollers (10) are driven by a motor (15, M1).

6. The petroleum well casing or tubing pipe recovery system of any of the preceding claims, - wherein said flattener rollers (10) and / or said pipe pulling rollers (11) are provided with studs (101) for engaging the casing or tubing pipe (00).

7. The petroleum well casing or tubing pipe recovery system of any of the preceding claims, - wherein said flattener rollers (10) are arranged as a parallel pair with generally horizontal axles (110), i.e. the axles (110) are arranged transverse to the axis of the out coming casing or tubing pipe (00).

8. The petroleum well casing or tubing pipe recovery system of any of the preceding claims, - wherein said axles (110) are suspended in an actuator mechanism (17) arranged for moving said rollers (10) into or out of flattening engagement with said out coming casing or tubing pipe (00).

9. The petroleum well casing or tubing pipe recovery system of any of the preceding claims, - wherein said pipe pulling mechanism (11) are suspended in an actuator mechanism (18) arranged for moving said rollers (11) into and out of pulling engagement with said out coming casing or tubing pipe (00).

10. The petroleum well casing or tubing recovery system of any of claims 8 or 9,

- wherein said squeeze roller actuator mechanisms (17) and said pulling roller actuator mechanisms (18) are suspended in an auxiliary rig frame (19).

11. The petroleum well casing or tubing recovery system of any of claims 1 - 10, comprising - a wireline drum (71) with a wireline (72) arranged for lowering a wireline conveyed casing cutter tool (75) into the well for severing said long length of casing or tubing (00) to be recovered from the well, and arranged for removing said wireline conveyed casing cutter tool (75) from the well before engaging said flattener squeeze rollers (10) with said severed casing or tubing (00).

12. A petroleum well casing or tubing pipe recovery method

comprising the steps of

- pulling casing or tubing pipe (00) out of a well by means of a pipe pulling mechanism (11) in a generally continuous manner,

- flattening said casing or tubing pipe (00) to a flat belt (12) using a set of two or more flattener "squeeze" rollers (10) while said casing or tubing pipe (00) emerges from said pipe pulling mechanism (11) ,

- conveying the resulting flat belt (12) away from the well.

13. The method of claim 12, comprising:

- receiving said flat belt (12) on a coil drum (20),

- winding up said flat belt (12) to a belt coil (14),

transporting away said belt coil (14) for steel waste recovery.

14. The method of claim 12, comprising

- cutting said flat belt (12) into belt sections (16) as said flat belt (12) emerges from said flattener rollers (10) and storing said belt sections (16) in one or more baskets or containers (44) for steel waste recovery.

15. The method of any of claims 12 - 14 , comprising

- on a well from which a casing or tubing (00) shall be removed,

- provide a frame (19) with a pipe pulling mechanism (11) and flattener rollers (10) on said well, and pull and flatten said casing (00) into a flat belt (12),

- run wireline tools such as cleaning or well logging tools including such wall thickness log, cement bonding log, for å cleaning a wall of a previously surrounding casing and / or logging the well after removal of said casing (00).