WO2019083372A1

WO2019083372A1 - A lifting assistant unit for lifting heavy loads

Info

Publication number: WO2019083372A1
Application number: PCT/NO2018/050243
Authority: WO
Inventors: Mads BJØRNENAK; Erik Zachariasen; Tom Fedog; Helge Skeie
Original assignee: Stimline As
Priority date: 2017-10-24
Filing date: 2018-10-11
Publication date: 2019-05-02
Also published as: NO20171702A1; NO342915B1

Abstract

The invention relates to a lifting device for assisting in lifting of heavy loads within a derrick. The lifting device comprises a frame structure (42) and a travelling block (43), said travelling block (43) being adapted to travel within said frame structure; said frame structure (42) being configured at a first end (44) to be supported by a drill floor (40); said travelling block (43), which is adapted to be connected to said heavy load to be lifted, having at least one sheave (14); at least one wire (13) extending around said sheave, said at least one wire (13) having a first end (41b), which is attached to said frame structure proximate to a second end (45) of said frame structure (42), said second end (45) facing away from said drill floor (40) when the lifting device (7) is in use; said at least one wire (13) having a second end (41a), which is adapted to be coupled to a derrick hoist (3, 4).

Description

A LIFTING ASSISTANT UNIT FOR LIFTING HEAVY LOADS TECHNICAL FIELD

The present invention relates to a lifting assistant unit for lifting heavy loads, such as casings, inside a derrick and through an opening in a drill floor. Casings and a few other heavy items are indeed necessary to handle at specific phases during oil and gas well drilling. However, most of the time the derrick hoisting system is handling substantially less heavy items. Nevertheless, the hoisting system has to be designed with a capacity to handle the heaviest loads to be lifted. Background Art

Few attempts have been made to improve the handling of heavy items, such as casings. US7350586, EP2208853, US9010410, US20150083391 are examples. However, all of these are either depending on the lifting capacity of the derrick hoist or are very bulky and complicated. Further, GB 2418684 A describes a lifting device within a derrick, which is characterized in that the lifting device comprises a frame structure and a winch, where said frame structure being configured at a first end to be supported by a surface tree and a second end facing away from said surface tree adapted to be coupled to a derrick hoist.

Summary of invention

The objective of the present invention is to enable drilling rigs, such as drilling vessels, to increase their lifting capacity beyond the capacity of the derrick hoist. This is done by mounting an additional lifting device inside the derrick, which is actuated by the derrick hoist.

This invention is using the standard top drive and lifting system on a drilling vessel to double the lifting capacity of the vessel. The top drive connects to a pipe shaped lifting collar and lifts the travelling block within a frame structure.

The result is that the lifting capacity is twice (depending on "gearing") the lifting capacity of the top drive / draw-works. The lifting speed of the lifting device of the invention is half of the top drive / draw-works, the lifting height of the lifting device is also half of the top drive / draw-works.

Brief description of drawings An embodiment of the present invention will now be described referring to the accompanying drawings, in which:

Figure 1 shows a derrick with the lifting device of the present invention in an isometric view,

Figure 2 shows the derrick with the lifting device of the present invention in an elevated view,

Figure 3 shows the derrick with the lifting device of the present invention in a planar view,

Figure 4 shows the lifting device of the present invention in an isometric view with the derrick removed but a top drive shown in an upper position, Figure 5 shows the lifting device of the present invention in an isometric view with the derrick removed but a top drive shown in a lower position,

Figure 6 shows the lifting device of the present invention in a planar view with the derrick removed,

Figure 7 shows the lifting device of the present invention in an elevated view with the derrick removed and the top drive in a lower position,

Figure 8 shows the lifting device of the present invention in an elevated view with the derrick removed and the top drive in an upper position,

Figure 9 shows the lifting device of the present invention in isometric view and in a lower position, Figure 10 shows the lifting device of the present invention in an elevated view,

Figure 1 1 shows the lifting device of the present invention in an elevated view about 90° relative to figure 10,

Figure 12 shows the mechanics of the lifting device of the present invention in an elevated view with the frame removed, and Figure 13 shows the mechanics of the lifting device of the present invention in an isometric view with the frame removed.

Detailed description of the invention Figure 1 shows a derrick 1 , which is situated on top of a drill floor 40. The shown derrick is a dual derrick that has two side-by-side arranged lifting spaces, which means that it has the capacity to run two parallel operations, one operation in each lifting space of the derrick. Hence, the derrick has been provided with the structural capacity to increase the lifted load beyond the max load of each top drive; the largest top drives today have a lifting capacity of 1250 tons.

Although the invention is described in connection with a dual derrick, it is also possible to use the invention within a single derrick.

Each of the lifting spaces of the derrick is provided with a pair of top drive guide rails 2, which extend vertically inside the lifting space. A top-drive travelling block 3 is suspended from the top of the derrick, and a top drive unit 4 is attached to the travelling block 3.

The top drive unit 4 suspends a top drive elevator 22 via top drive elevator links 16. (Figure 4) One of the top drive units 4 is hanging directly above a main well centre 5 in the drill floor 40, which the top drive unit (not shown) in the other lifting space is hanging directly above an auxiliary well centre 6.

A lifting device according to an embodiment of the present invention is denoted by reference number 7. The lifting device 7 is arranged on the drill floor directly above the well centre 5. Figures 2 and 3 show the derrick 1 with the lifting device 7 in alternate views.

Figure 4 shows the lifting device 7 in a view where the derrick 1 has been removed for clarity. The figure also shows the travelling block 3 and the top drive unit 4, as well as a top drive guide dolly that couples the top drive unit 4 with the guide rails 2.

The lifting device 7 comprises a frame structure 42, which in this embodiment consists of an upper frame section 8 and a lower frame section 9, which are fixedly joined at a frame joint 10. It is also possible that the frame structure 42 consists of a single unitary frame or more than two frame sections.

The frame structure has a lower end 44, which is resting against the drill floor 40 when the lifting device 7 is in use, and an upper end 45, which is facing away from the drill floor 40.

In the embodiment shown, the frame structure has a triangular cross section. However, other cross-sections are also conceivable.

A travelling block 43 is arranged within the frame structure 42. The travelling block 43 is capable of travelling along substantially the whole length of the lifting frame.

The lifting device 7 will now be described in more detail, referring to figure 9.

The frame structure 42 comprises a pair of parallel guide rails 32. A guided travelling frame 33 is adapted to run along the guide rails 32 on guide wheels 38.

Further details of the mechanics of the lifting device 7 is shown in figures 12 and 13. The travelling frame 33 is attached to a rotating actuator 35 with a main bearing 36. An elevator 18 is coupled to the rotating actuator 35 via elevator links 29 and a hydraulic swivel 37. A yoke 17 with a pair of sheaves 14 is coupled to the opposite of the rotating actuator 35. The sheaves are rotatably mounted to the yoke 17 about a sheave shaft 34.

A set of lifting wires 13 extends about each of the sheaves 14. The lifting wires 13 have a first end 41 b and a second end 41 a. The first end 41 b is attached to the upper end of the frame structure 42 at a connection 1 1 . The second end 41 a is attached to a lifting collar 30. The second end 41 a is attached to the lifting collar 30 at a connections, (see figure 9).

The guide rails 32 are arranged on each side of an opening 46 in the frame structure 42. The opening 46 extends along the length of the frame structure 42, so that there is open access provided at one side of the travelling frame 33 for inserting casing pipes or other heavy objects to be lifted by the lifting device. Reverting back to figure 4, is shown that the lifting collar 30 has been gripped by the elevator 22 of the top drive unit 4.

The lifting unit 7 is conveniently placed directly on the drill floor 40, so that it is supported vertically by the drill floor 40. Thereby any weight acting on the lifting device 7 will be transferred to the drill floor 40.

Figure 4 shows a casing pipe 28 suspended in the elevator 18 of the lifting device 7. The casing pipe 28has been brought into the lifting device 7 by means not shown, but which are per se conventional in the field.

When the casing pipe 28 is suspended in the lifting device 7, the weight of the casing pipe 28 will be transferred to each end 41 a and 41 b of the lifting wires, with half of the weight being transferred to the frame structure 42 via the connection 1 1 and half of the weight being transferred to the top drive via the collar 30 and the elevator 22.

The part of the weight that is transferred to the frame structure 42 will be directly transferred to the drill floor. Consequently, the top drive unit and the hoisting system of the derrick need only carry half the weight of the casing pipe, and more importantly, the weight of the whole casing string.

The halving of the weight on the hoisting system of the derrick is of course on the expense of travel distance. As seen by comparing figure 4 and figure 5 the top drive unit 4 has travelled the double distance of the travelling frame 31 when the casing pipe 28 has been lowered from the position shown in figure 4 to the position shown in figure 5.

As also can be seen in figure 5, the frame structure 42 is designed to

accommodate the top drive unit 4 and the travelling block 3. This provides maximum lifting height.

When one casing pipe has been lowered through the well centre 5, slips (not shown) are applied to hold the upper end of the casing pipe. The elevator 18 of the lifting device 7 is released, and the travelling frame unit 31 is hoisted back up to its upper position within the frame structure 42, as shown in figure 4 and figure 8. In this position, another casing pipe is brought into a position to be gripped by the elevator 18. The lower end of the new casing is then coupled to the first casing that is suspended by the slips to form a casing string 27. This is done by rotating the new casing using the rotating actuator 35 and thereby screw the new casing onto the top end of the previous casing. Now the slips can be opened and the casing string 27 is lowered through the well centre 5. More casing pipes 28 are added in the same way until the casing string 27 is complete.

The lifting device 7 will be stored outside the derrick when not in use. When it is to be used, it will be hoisted into the derrick by a per se known lifting appliance. The top-drive unit may be connected to the frame structure 42 and used to lift the lifting device 7 into the derrick and place it on the deck 40.

The deck 40 may have especially prepared slots to receive the lifting device 7 or it may be held in place by stays extending at a slant from the frame structure 42 to attachments on the deck or from the frame structure to the derrick structure.

ID name

1. Derrick

2. Top drive Guide rails

3. Top drive travelling block

4. Top drive

5. Main well center

6. Aux well center

7. Casing running tower

8. Casing Running tower upper frame

9. Casing Running tower lower frame

10. Casing running tower frame joint

11. Casing running unit wire connection frame

12. Casing running unit wire connection travelling unit

13. Casing running unit lifting wire

14. Casing running unit sheave

15. Casing running unit lifting yoke shaft

16. Top drive elevator links

17. Casing running unit yoke

18. Casing running unit elevator

19. Casing Traveling Block

20. Casing running unit torque wrench

21. Casing running unit lifting yoke

22. Top drive Elevator

23. Power Slips

24. Casing running unit link hanger

25. Top drive guide dolly . Casing running frame

. Casing string

. Casing pipe

. Casing running unit elevator links. Casing running tool lifting collar. Casing running unit (whole unit). Casing running unit guide

. Casing running unit guide frame. Casing running unit wire sheave shaft. Casing running unit rotating actuator. Casing running unit main bearing. Casing running unit hydraulic swivel. Casing running unit guide wheels. Casing running unit lifting yoke. Drill floor

. Frame structure completea Frame wire connection

b Lifting collar wire connection. Frame structure complete

. Travelling block

. Lower end of frame

. upper end of frame

. opening

Claims

1 .

A lifting device for assisting in lifting of heavy loads within a derrick,

characterised in that it comprises a frame structure (42) and a travelling block (43), said travelling block (43) being adapted to travel within said frame structure; said frame structure (42) being configured at a first end (44) to be supported by a drill floor (40); said travelling block (43), which is adapted to be connected to said heavy load to be lifted, having at least one sheave (14); at least one wire (13) extending around said sheave, said at least one wire (13) having a first end (41 b), which is attached to said frame structure proximate to a second end (45) of said frame structure (42), said second end (45) facing away from said drill floor (40) when the lifting device (7) is in use; said at least one wire (13) having a second end (41 a), which is adapted to be coupled to a derrick hoist (3, 4).

2.

The lifting device of claim 1 , characterised in that said frame structure (42) has at least one rail (32) extending along said frame structure, said travelling block (43) interacting with said rail (32) to be guided when travelling along said frame structure (42).

3.

The lifting device of claim 2, characterised in that said frame structure (42) has two rails (32) that are arranged on opposite sides of a longitudinal opening (46) in said frame structure (42).

4.

The lifting device of claim 2, characterised in that said travelling block (43) has a travelling frame (33), which is guided by said rails (32).

5.

The lifting device of any of the preceding claims, characterised in that said travelling block (43) has a yoke (39), said yoke (39) carrying two sets of sheaves (14), a set of wires (13) extending around each set of sheaves (14).

6.

The lifting device of any of the preceding claims, characterised in that said frame structure (42) comprises at least two frame structure modules (8, 9).

7.

The lifting device of any of the preceding claims, characterised in that said travelling block comprises a rotating actuator capable of rotating said heavy load.