JPS5932637B2 - Connection device for inner pipe for riser pipe - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a connecting device for internal pipes such as hydraulic pipes arranged in the axial direction within a riser pipe. This relates to a coupling device that prevents oil leakage and air mixing into hydraulic pressure.

In the field of offshore oil development, offshore wellheads, drilling vessels,
The pipe that connects marine facilities such as support ships is called a riser pipe.

There are various types of riser pipes depending on the purpose of use, such as marine risers, combination risers, and production risers, but in many cases, internal pipes such as hydraulic pipes for working on the seabed are used. have.

FIG. 1 shows the connected state of conventional riser pipes, in which the first and second riser pipes 1a and 1b have the same shape.
are connected via an end support 2a, and several dozen riser pipes 1, 1°, . . . are connected in sequence for use.

That is, a first end support 2a is fixed to the end of the first riser pipe 1a, and a second end support 2b is fixed to the second riser pipe 1b. In the connected state shown in the figure, it is inserted into the connecting end 3 of the mating riser pipe 1b, and is fixed to the connecting end 3 by a connecting tool 5 that is movable in the radial direction and has a wedge-shaped projection 4.

By retreating the connector 5 in the direction of the arrow 6 and releasing the engagement between the draft-like protrusion 4 and the groove 7 on the outer periphery of the end support 2a, the first riser pipe 1a and the end support 2a to which the first riser pipe 1a is fixed are removed. It can be separated from the riser pipe 1b of No. 2.

The ends of internal pipes 8 and 9 disposed in the riser pipe in the axial direction are inserted into the above-mentioned both end supports 2a and 2b, and the abutted both end supports F 2 a and 2
Connecting pipes to, ii are installed across b.

Therefore, for example, the inner pipes 8 and 8 in the connected riser pipes la and Ib are connected to the end support 2a.

The oil passages 12, 13 and 2b communicate with each other via the connecting pipe 10.

In conventional riser pipes like this, both ends of the inner pipe and connecting pipe are open, so when the riser pipe is disconnected, the hydraulic oil inside the inner pipe leaks, and hydraulic oil must be injected after connection. However, lubricating several hundred meters of riser pipe is a time-consuming and labor-intensive task.

In addition, with this type of lubrication method, it is impossible to avoid air and foreign matter from getting into the hydraulic fluid, and once air is mixed in, it cannot be easily evacuated, resulting in a decrease in the accuracy of valve operations, etc. invite.

Furthermore, in this case, a bypass mechanism must be provided at the lower end of the riser pipe to remove air and foreign matter, which complicates the apparatus.

The present invention aims to eliminate the inconveniences of such conventional connection devices for inner pipes for riser pipes, and provides a connection device that allows inner pipes to be connected and disconnected while sealing hydraulic oil inside the inner pipe. It provides:

Next, embodiments embodying the present invention will be described in detail with reference to the accompanying drawings starting from FIG.

Here, FIG. 2 is a side sectional view showing the connected state of the connecting device according to the first embodiment, FIG. 3 is a side sectional view showing the state of the device before connection, and FIGS. , a schematic side sectional view showing the flow of hydraulic oil in the device, and FIG. 5 is a side sectional view of a coupling device showing the second embodiment.

In FIGS. 2 and 3, reference numeral 3 denotes the connecting end of the second riser pipe, which has the end support 2b fixedly, as described above.

Reference numeral 2a denotes an end support that is inserted into the connecting end 3 and fixed to the connecting end 3 by a connecting tool 5 (FIG. 1) when the connection is completed.

The fixed cylinder 2 of the female side communication pipe 20 is attached to the end support 2a.
1 is screwed on.

A guide tube 23 having a sleeve 22 is fixed to this fixed cylinder 21 .

A spring chamber 24 is formed between the sleeve 22 and the fixed cylinder 21, and a sliding cylinder 26 having a sleeve 25 inserted into the spring chamber 24 is slidable in the axial direction of the communication pipe 20. , is constantly biased in the direction of arrow X by a compression spring 27 within the spring chamber 24.

The nose portion 28 of the fixed cylinder 21 is connected to the end support 2
A blind oil passage 3 is provided at the tip 30 of the sliding cylinder 26 that protrudes from the front surface 29 of the cylinder a and reaches into the nose portion 28.
1 is formed.

The communication hole 33 provided in the step portion 32 of the sliding cylinder 264 and the communication hole 35 provided in contact with the step portion 34 are connected to the oil passage 3, respectively.
Connected to 1.

In the state before connection, as shown in FIG. 3, the communication holes 33 and 35 are closed by the fixed cylinder 21, and the oil passage 31 is in a sealed state.

A space 38 having a stroke l is formed between the end 36 of the sleeve 22 and the step 37 of the sliding cylinder 26.

Therefore, when the sliding cylinder 26 moves in the direction of arrow Y during connection, there is a gap between the step 34 of the sliding cylinder 26 and the step 39 of the fixed cylinder 21 depending on the amount of movement of the sliding cylinder 26. An oil storage chamber 40 having a volume of 1.5 mm is formed, and the oil storage chamber 40 and the oil passage 31 are connected through a communication hole 35.

On the other hand, the male side connecting pipe 41 screwed onto the end support)-2b
A guide cylinder 42 fixed to the end support 2b, a socket valve 43 fixed to the guide cylinder 42,
It has a slidable slide valve 44 which is sandwiched between a socket valve 43 and a guide cylinder 42.
is constantly biased in the direction of arrow Y by a compression spring 46 assembled between the step portion 45 of the guide cylinder 42 and the step portion 45 of the guide cylinder 42 .

The oil passage 47 inside the socket valve 43 is in a blind state, and the socket valve 4
A communication hole 48 that communicates with an oil passage 47 bored at the end of 3 is sealed by a slide valve 44 before connection as shown in the 3rd figure.

In the figure, 49 is a sealing member, and 50 is a stop ring that is abutment for the slide valve 44.

Further, the oil passage 31 communicates with an oil passage 12 similar to the one shown in the first diagram provided in the end support 2a, and the oil passage 47 communicates with the oil passage 13 on the end support 2b side.
13 communicates with the inner pipe.

Reference numerals 51 and 52 are holes into which tools are inserted when screwing the fixed cylinder 21 and the guide cylinder 42 together.

Next, the operation of connecting the communication pipes 20 and 41 will be explained.

When the end support 2a is slid in the direction of arrow X from the state shown in FIG. Slide it against the

At the same time, the tip of the socket valve 43 hits the tip of the sliding cylinder 26, and the sliding cylinder 26 moves in the direction of arrow Y against the compression spring 27.

The spring chambers 24 and 24' only contain compressible air, and as the sliding cylinder 26 moves, the oil passage 3
A part of the incompressible hydraulic oil in 1 flows into the oil storage chamber 40 through the communication hole 35, and the rest flows into the space 53 created by the movement of the sliding cylinder 26 through the communication hole 33. The moving cylinder 26 moves easily.

By moving the sliding cylinder 26 and the slide valve 44 that close the communication holes 33 and 48, the communication holes 33 and 48 are moved as shown in the second figure.
．． 48 is opened, and this communication hole 33.48 and space 53
The oil passages 31 and 47 communicate with each other via.

Next, the volume of the oil storage chamber 40 will be considered.

As shown in FIGS. 4a and 4b, by the movement of the sliding cylinder 26,
The volume of the space 38 is reduced, and a portion of the hydraulic oil removed by the volume reduction flows into the oil storage chamber 40, and the remainder flows into the space 53.

Also, the tip male part 43' of the socket valve 43 is connected to the nose tip female part 2.
All of the hydraulic oil that is removed by being inserted into 8' flows into the oil storage chamber 40.

Therefore, if the volume of the oil storage chamber when the connection is completed is vl, the volume of the space 53 is v2, the volume displaced by the socket valve 43 is V3, and the volume of the space 38 before connection is v4, then the volume of v4 - v2, and V3 Since a volume of hydraulic oil flows into the oil storage chamber 40, the volume V1 of the oil storage chamber 40 must be determined as V1 = v3 + (V4 - v2). By satisfying this condition, a permanently sealed type Connection of the communication pipes 20 and 41 becomes possible.

FIG. 5 relates to a second embodiment in which the volume V1 of the oil storage chamber 40 is made equal to the volume V3 displaced by the socket valve 43.

Components common to those in the first embodiment are given the same reference numerals.

In this case, a compression spring 27 that biases the sliding cylinder 26 is disposed in a space 38' whose volume changes as the sliding cylinder 26 moves, and the volume v5 of the volume change 54 of this space 38' is , is formed to be equal to the volume V2 of the space 53, so that the entire amount of hydraulic oil displaced by the socket valve 43 flows into the oil storage chamber 40.

54' is an air vent hole. In any of the embodiments described above, when the connection is released, the compression springs 27 and 46 cause the sliding cylinder 26 and the slide valve 44 to return to their original positions. While the hydraulic oil flows back into the oil passage, the communication hole 3
3.48 is blocked by the fixed cylinder 21 and the slide valve 44, and both oil passages 31 and 4B return to the sealed state, so the oil passages 31 and 4B are closed.
The hydraulic oil in 47 will not leak out during connection and disconnection operations, and excess air will not be mixed in.

As described above, in the present invention, since both ends of the internal pipe in the riser pipe are always closed with sealed communication pipes, there is no need to replace the hydraulic oil each time the riser pipe is connected or disconnected. Since air and foreign matter do not get mixed into the hydraulic oil during separation, etc., the operating accuracy of valves at the bottom of the mine improves.

In addition, since an oil storage chamber is provided in the connecting pipe into which the hydraulic oil removed by the connecting connecting pipe flows when connected, the connecting operation can be performed without difficulty even if the hydraulic oil is incompressible. To provide a connection device for an inner pipe for a riser pipe that is extremely easy to handle because no hydraulic oil in the inner pipe leaks during connection and disconnection operations.

[Brief explanation of drawings]

FIG. 1 is a side sectional view showing a connected state of a conventional riser pipe, FIG. 2 is a side sectional view showing a connected state of a connecting device according to the first embodiment, and FIG. 3 is a side sectional view showing a connected state of the connecting device according to the first embodiment. 4a and 4b are schematic side sectional views showing the flow of hydraulic oil in the device; FIG. 5 is a side sectional view of the coupling device showing the second embodiment; FIG. be. (Explanation of symbols), la, 1b...first and second riser pipes, 2a, 2b...first and second end supports, 8, 9...・Interior pipe, 20...
...Female side communication pipe, 41...Male side communication pipe,
26...Sliding cylinder, 21...Fixed cylinder, 31...Oil passage in female side communication pipe, 40...
...Oil storage room.

Claims (1)

[Claims] 1 First and second riser pipes 1at1b to be connected
first and second end supports attached to the ends of) 2a
, 2b, the ends of the inner pipes 8 and 9 disposed inside the riser pipe are attached to fix the inner pipes to the riser pipe, and each inner pipe is connected to the connecting pipes 20 and 41 attached to both end supports respectively. In a connection device for internal pipes for riser pipes, each of the above-mentioned communication pipes is of a normally sealed type that is opened only when connected, and each communication pipe to be connected has a connection structure by male and female fitting. None, a sliding cylinder 26 is provided in the female connecting pipe 20 that slides when the male connecting pipe 41 is inserted, and communicates with the oil passage 31 in the female connecting pipe, and its volume changes as the sliding cylinder moves. An oil storage chamber 40 is provided in the female side connecting pipe, and when the male and female connecting pipes are connected, the amount of hydraulic oil that is removed by inserting the male side connecting pipe into the female side flows from the oil passage into the oil storage chamber and the oil passage is filled. A connecting device for an inner pipe for a riser pipe, characterized in that it is designed to absorb changes in volume.