JPS5824595B2 - Tree cap for wellhead equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a tree cap for a wellhead device,
During maintenance of wellhead equipment used in offshore oil production, it can be installed and removed in a short time, improving work efficiency.

The currently adopted tree cap for wellhead equipment will be explained based on FIG.

A is a tree manifold of a wellhead device, which has a locking recess at its upper end.

C is a tree cap, as shown below.

That is, a seal body e in the shape of a cylindrical container having a locking recess f on the inside is integrally attached to the ceiling atrium of a cylindrical tree cap frame d having a ceiling part and having different diameters. A piston ring g is slidably provided on the inner wall of the tree cap frame d, and the piston ring g and the tree cap frame are connected to each other. A cylindrical space i is formed between the cylindrical space d and the cylindrical space i.

Oil passages J and k are bored in the tree cap frame d so that one end opens at i and the other end opens at the upper surface of the tree cap frame d, and between the piston ring g and the seal body 0,
A plurality of lock segments 1 are shaped like "<" and have a locking protrusion that fits into the locking recess of the tree manifold a.The lock segments 1 are arranged at appropriate intervals and their central bent portions engage with the stepped portion of the seal body e. The tree manifold a can be locked and unlocked by moving the piston ring g up and down.

Further, as described above, the tree camp C is covered with a tree cap cover m to protect the cylinder drive line of the tree cap C having a built-in hydraulic cylinder.

The above-mentioned tree cap cover m has a hollow body 0 with a flange that has a recess for locking with a running tool n at the upper end, and a cylindrical body p that is integrally fitted below the flange of the solid body 0. A plurality of tapered lock pins q fit into the lock recesses f in the seal body e at the same time in the radial direction and are retracted in the radial direction against the spring γ force or by the spring γ force. It's starting to stand out.

When performing maintenance, etc., first lock the claw of the running tool n into the locking recess of the solid body 0 of the tree camp cover m and lift it up.The lock pin q has a tapered shape, so the tree cap It is pushed by the fitting slope of the locking recess f of the seal body e of C and moves inward, that is, it is pulled in against the spring γ, and the lock with the seal body e is released. The tree cap cover m will be removed from the tree cap C.

After that, a pressure oil supply device for supplying pressure oil to the hydraulic line of the tree cap C is connected to the tree cap C, pressure oil is supplied to the cylindrical space, and the piston ring g is attached to the tree cap frame d. As the lock segment I rises along the inner wall, the upper end of the lock segment I rotates inwardly and the lower end rotates outwardly using the engagement portion with the seal body e as a fulcrum, thereby causing the lock segment I and the tree manifold to rotate. The locking concave part a is now unlocked, and in this state, the pressure oil supply device and the tree cap C are removed from the tree manifold a, and the tree manifold a is maintained.

After the maintenance is completed, install the tree cap C and tree cap cover m to the tree manifold a by performing the work in the reverse order as described above.

The tree cap described above has a complicated structure because it is a cylinder type with a built-in liquid, and requires a tree cap cover to protect the hydraulic drive line, which requires installation and removal work in two stages during maintenance etc. There were disadvantages such as the need to carry out the work and the time required for the work.

The present invention relates to a tree cap for wellhead equipment made in view of the above-mentioned circumstances, in which a pull rod having a stepped portion at the lower end is movably inserted into a cylindrical tree cap body having a locking portion at the upper end. Between the pull rod and the tree cap frame, a plurality of "<"-shaped lock segments having a lock part with the tree manifold at the lower end are connected, and the central protrusion is engaged with the stepped part of the pull rod. It is characterized in that it is arranged so that the engaging portion of the mating portion rotates in the radial direction as the tree cap frame moves up and down.

Embodiments of the present invention will be described below based on the drawings.

A protruding surface 2 is provided at the center of the inner wall of a cylindrical tree camp frame 1 having a cylindrical atrium in the ceiling, and the inner wall between the protruding surface 2 and the lower end of the tree cap frame 1 is sloped appropriately. A guide groove 3 is formed in the inner wall between the ceiling part of the tree cap frame 1 and the protruding surface 2 in the axial direction, and Four locking parts 4 are provided at the upper end of the tree cap frame 1.

A pull rod 5 having four locking parts 6 at the upper end and a stepped part 7 at the lower end is movably inserted into the tree cap frame 1, and at the center of the pull rod 5,
A collar 8 having a diameter larger than the inner diameter of the protruding surface 2 of the tree cap frame 1 is attached, and a guide member 9 is attached to the side surface of the collar 8 so as to fit into the guide groove 3 of the tree cap frame 1. can move in the axial direction of the tree cap frame 1.

Furthermore, between the lower end of the pull rod 5 and the lower end of the inner wall of the tree cap frame 1, there is a lock segment 10 in the shape of a "<" having a convex portion at the lower end that fits into the locking recess 12 of the tree manifold 11. are disposed at required intervals with their central protruding portions engaged with the stepped portions 7 of the pull rods 5, so that as the tree cap frame 1 moves up and down, the lock segments 10 move around the retaining portions. It should be able to rotate in the radial direction (see Figures 2 and 3).

In the figure, 13 is a positioning pin, and 14 is a seal body.

The removal work of the tree camp configured as described above will be described.

First, the lifting device and the locking recess 6 of the tree cap frame 1
When the tree cap frame 1 is raised along the guide member 9, the lock segment 10 rotates around the engagement part with the stepped part 7 of the pull rod 5 so that its lower end opens. This means that the lock with the tree manifold 11 is released.

That is, the state changes from the left half state in FIG. 2 to the right half state.

When the tree cap frame 1 is raised in this state, the pull rod 5 is raised together with the tree cap frame 1 while being supported by the protruding surface 2 of the tree cap frame 1.

In this way, attach the tree cap to the tree manifold 1
Remove and perform maintenance etc. from 1.

If you want to attach the tree cap, perform the procedure in reverse order.

At this time, positioning is performed reliably using the positioning pins 13.

Next, a running tool used for attaching and detaching the tree cap mentioned above will be explained.

A ring-shaped protrusion having an inner diameter equal to the outer diameter of the ring-shaped protrusion of the rod 15 and a ring-shaped protrusion having a diameter equal to the outer diameter of the rod 15 is attached to the axially center part of the inner wall of the rod 15 having a ring-shaped protrusion at the axial center. The cylindrical body 16 with its protruding force button 15
It is slidably fitted so that it is located below the protrusion of
A cylindrical body 17 having a sealed space 18 inside and having an inner diameter equal to the upper outer diameter of the cylindrical body 16 is integrally attached to the upper outer circumference of the cylindrical body 16, and is movable in the axial direction to a desired location on the cylindrical body 17. A plurality of guide rods 19 are provided through the guide rods 19 .

Further, a ring 20 having an inner diameter equal to the outer diameter of the rod 15 is slidably fitted above the rod 15, and
A ring 20 is airtightly attached to the upper surface of the cylindrical body 16, and a sealed space 21 is formed between the ring 20, the cylindrical body 16, the rod 15, and the protrusion of the rod 15, and between the rod 15, the protrusion of the rod 15, and the cylindrical body 16. A sealed space 22 is formed from each of the protrusions of the cylinder 16, a disk 23 having a larger diameter than the rod 15 is attached to the upper surface of the rod 15, the upper end of the guide rod 15 is connected to the disk 23, and the cylinder 16 is connected to the upper end of the guide rod 15. A plurality (three in the drawing) of cylinders 24 with built-in springs for gripping the tree cap frame 1 of the tree cap are provided at a required interval radially at the lower end of the cylinder, and the pull rod 5 of the tree cap is gripped. With the two cylinders 25 with built-in springs facing each other, the rod 15 should be positioned appropriately above the cylinders 24. (according to the spacing between the four locking parts 4 of the cap frame 1 and the locking recess 6 of the pull rod 5),
A notch 26 is provided in the cylindrical body 16 so that the cylinder 25 does not get in the way when the cylindrical body 16 moves.

In FIG. 4, reference numeral 27 denotes an oil passage which is bored horizontally in the disc 23 and communicates with the upper surface of the disc 23 through holes 28 at required points;
29. Reference numeral 30 indicates a through hole drilled in the axial direction at a required location of the disk 23, and 31 indicates an oil passage provided in the rod 15, with one end opening into the through hole 29 and the other end opening into the sealed space 21. 32 is an oil passage provided in the rod 15, with one end opening into the through hole 30 and the other end opening into the sealed space 22, and 33 an oil passage provided in the rod 15 with one end opening into the through hole 30 and the other end opening into the closed space 22. 34 is an oil passage provided in the cylinder body 16, which communicates with the cylinder chamber of the cylinder 25 and the other end communicates with the oil passage 27, and the other end communicates with the cylinder chamber of the cylinder body 17, and the other end communicates with the oil passage 27. 35 is an oil passage provided in the guide rod 19, one end of which communicates with the sealed space 18 of the cylinder 17, and the other end of which communicates with the oil passage 27.

The operation of the running tool having the above configuration will be explained.

Connecting the pressure oil supply device to the hole 28 and the through hole 29.30,
Pressure oil is supplied to the closed space 22 through the through hole 30 and the oil passage 32, and from the closed space 21; pressurized oil is discharged through the oil passage 31 and the through hole 29, and the cylinder bodies 16 and 18 are lowered together. Then, as shown in the left half of FIG. 4, pressure oil is supplied to the cylinder chamber of the cylinder 25 through the oil passages 27 and 33, and the piston rod of the cylinder 25 is brought into a retracted state against the spring force. Pressure oil is supplied to the cylinder chamber of the cylinder 24 through the oil passages 27, 35, the sealed space 18, and the oil passage 34, so that the piston rod of the cylinder is retracted against the spring force.

In this state, when the tree manifold 11 is locked onto the tree cap, the cylinder 24 faces the locking recess 4 of the tree cap frame 1, and the cylinder 25 faces the locking recess 6 of the pull rod 5, respectively.

Next, the supply of pressure oil to the oil passage 27 through the hole 28 is stopped to reduce the pressure.

Then, the piston rods of the cylinders 24 and 25 are respectively projected by the spring force, and the piston rods of the cylinder 24 and 25 are inserted into the locking recess 4 and the locking recess 6, respectively, and are locked.

In this locked state, the through hole 29 and the oil passage 3 are inserted into the closed space 21.
Pressure oil is supplied through 1 and discharged from the closed space 22 through an oil passage 32 and through hole 30.

Then, the state will be as shown in the left half of FIG. 4, and the tree cap and tree manifold 11 will be unlocked as shown in the left half of FIG. transport.

A running tool is used to remove the tree cap from the tree manifold as described above.

Also, the work of attaching the tree cap to the tree manifold can be performed by reversing the above procedure.

It should be noted that the present invention is not limited to the illustrated and described embodiments; for example, the attachment/detachment work may be performed using a running tool of a type other than the running tool shown in FIGS. 4 and 5, and the tsuba 8 may be Omissions, etc. are optional, and it goes without saying that various changes can be made without departing from the gist of the present invention.

As described above, according to the tree cap of the present invention, (:) the process of attaching and detaching can be shortened, and the working time can be significantly shortened.

(il) Easy to operate.

(iii) The structure is simple and assembly is easy.

Demonstrates excellent effects such as

[Brief explanation of the drawing]

Fig. 1 is an explanatory vertical sectional view showing the structure and operating state of a conventional tree cap, and Fig. 2 is an explanatory longitudinal sectional view showing the structure and operating state of the tree cap of the present invention.The left half is a tree manifold. The right half shows the locked state, and the right half shows the unlocked state. Fig. 3 is a view taken in the direction of arrow l in Fig. 2. Fig. 4 shows the running tool for attaching and detaching the tree cap of the present invention. This is an explanatory partial cross-sectional view showing an example, and the left half shows the tree cap of the present invention in a locked state, and the right half shows the tree cap of the present invention in an unlocked state. The figure is a view taken in the direction of the ■ arrow in FIG. 4. 1...Tree cap frame, 4...Lock recess, 5...Pull rod, 6...
Locking recess, 7... Step portion, 10...
- Lock segment, 11...Tree manifold.

Claims (1)

[Claims] 1. A pull rod having a stepped portion at the lower end is movably inserted into a cylindrical tree cap body having a locking portion at the upper end, and a tree manifold is inserted at the lower end between the pull rod and the tree cap frame. A plurality of "<"-shaped lock segments each having a locking part are engaged with the central protrusion in the step part of the pull rod, and the lock segments are rotated in the radial direction by raising and lowering the tree cap frame at this engaging part. A tree cap for a wellhead device, characterized in that a pull rod and a tree cap are arranged so as to be mechanically locked and unlocked.