JPH03265781A - Fluid transport pipe - Google Patents

Abstract

PURPOSE:To realize reduction of weight, detection of breakdown of a reinforcing layer, and temperature preservation and heating of a transport fluid by providing a plastic pipe on a metallic interlock pipe, and providing a carbon fiber reinforcing layer thereon, and providing an outer sheath on the carbon fiber reinforcing layer. CONSTITUTION:This is composed of a flexible composite pipe 1, that is, the metallic interlock pipe 2, where an metallic tape whose cross section is S-shaped, for example, a steel tape is wound into tubular shape and uneven parts are engaged with each other, a plastic pipe 3 which is made on the interlock pipe 2 by extrusion coverage, or the like, carbon fiber reinforcing layers 4 and 5, which are provided on the plastic pipe 3, and an outer sheath 6 of plastic, which is provided on these reinforcing layers 4 and 5. As a result, sharp weight reduction of a fluid transport pipe can be realized. Moreover, abnormality such as the deformation of the reinforcing layer, breakdown, etc. can be detected by the change of electric resistance.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a flexible composite pipe for transporting fluids such as oil and gas, particularly crude oil and natural gas extracted from oil wells, gas wells, etc. The present invention relates to a fluid transport pipe.

[Conventional technology]

Conventional fluid transport tubes consist of a flexible composite tube with a plastic tube on top of a metal interlock tube, a metal reinforcing layer on top of the plastic tube, and an outer sheath on the metal reinforcing layer. ing.

[Problem to be solved by the invention]

However, since conventional fluid transport pipes use a metal reinforcement layer, they have a large weight per unit length.Especially in recent years, as offshore oil fields have been developed from shallow waters to offshore deep waters, long transport pipes are being used more frequently, and the thickness of the reinforcing layer has become larger in order to support its own weight, which tends to increase the weight. For this reason, manufacturing, transporting, and constructing the transport pipes are troublesome and costly, which poses the problem of being uneconomical.

Furthermore, when transporting a fluid with low fluidity, the fluid may be heated through a heat exchanger or the like to increase its fluidity before being transported. At this time, protect the transport pipe with foamed plastic, etc.
i, wrapping a heater around the transport pipe, or providing a heater layer inside the transport pipe.

However, by providing a heat insulating layer, the outer diameter of the composite pipe increases significantly, and when the transport pipe is used in the ocean, it becomes more susceptible to the effects of waves, etc., and when the transport pipe is wound onto a drum, etc.
The amount of roll (storage amount) was reduced, which caused many practical problems.

On the other hand, the heater winding structure has a problem in that the fluid transport pipe is repeatedly bent by waves and currents, and the heater tends to burn out.

Furthermore, if the fluid transport pipe is subjected to repeated bending and the metal reinforcing layer suffers fatigue failure, this cannot be detected promptly and if left untreated, the fluid transport pipe will eventually break and become unable to transport fluid. There was a risk of causing a serious disaster such as contaminating the surrounding area with oil, etc.

[Means to solve the problem]

The present invention has been made to solve the various problems mentioned above, and the invention as claimed in claim 1 provides a plastic pipe on top of a metal interlock pipe, and a carbon fiber reinforcing layer on top of the plastic pipe. It consists of a flexible composite tube with an outer sheath over a carbon fiber reinforcement layer. The invention according to claim 2 is the fluid transport pipe according to claim 1, wherein electrical insulation is provided between the end of the interlock pipe and the end of the carbon fiber reinforcing layer at one end of the flexible composite pipe. Attach the insulating side terminal fitting L3, connect a reinforcing layer abnormality detector between these two terminals, and connect the terminal of the interlock tube and the terminal of the carbon fiber reinforcing layer to the other terminal of the flexible composite tube. It is constructed by attaching a conductive side terminal fitting to electrically connect and conduct between the two.

According to a third aspect of the invention, in the fluid transport pipe according to the second aspect, a heating power supply device is connected in place of the reinforcing layer abnormality detector.

(Function) Since a carbon fiber reinforced layer is used as a reinforcing layer, the weight per unit length is lighter than that of a metal reinforced layer.In particular, carbon fiber reinforced plastic is about 1/2 the weight of widely used steel materials.
Since the weight is about 6, the fluid transport tube made of this plastic and made of a flexible composite tube with a carbon fiber reinforcement layer can significantly reduce the weight.

Further, the carbon fiber reinforced layer is conductive, and its volume resistivity is, for example, 1 to 10 in the case of carbon fiber reinforced plastic.
Since it is 6Ω・0, by measuring the resistance,
Breakage of the reinforcing layer can be detected.

Furthermore, by constantly passing an appropriate current through the carbon fiber reinforcing layer, the reinforcing layer generates heat, and the transport fluid can be kept warm or heated.

〔Example〕

(First Embodiment) Next, a first embodiment of the present invention will be described in detail with reference to FIG. A metal interlock tube 2 in which an S-shaped metal tape, for example, a steel tape, is wrapped around a tube and the concave and convex portions are interlocked with each other; a plastic tube 3 formed on the interlock tube 2 by extrusion coating or the like; It consists of a flexible composite tube consisting of a carbon fiber reinforcement layer 4.5 provided on the plastic tube 3 and a plastic outer sheath 6 provided on the reinforcement N4.5.

The carbon fiber reinforcing layer 4 is to withstand the internal pressure from the plastic pipe 3, and is made of a long length of carbon fiber reinforced plastic with a chevron-shaped cross-section having a concave portion in the center and convex portions on both side edges, as shown in the figure. The body is formed by stacking two layers in opposite directions and wrapping them in a short pitch while interlocking the uneven parts, or having a protrusion on one side edge and a convex part on the other side edge.
A carbon fiber-reinforced plastic elongated body having a Z-shaped cross section and a concave portion corresponding to the convex portion is wound with short pitches so that the concave and convex portions engage, or a carbon fiber-reinforced plastic tape or a carbon fiber woven strip is formed. It is formed by winding it in multiple layers. The carbon fiber reinforcement layer 5 is intended to withstand the axial force generated by internal pressure, its own weight, and the axial force generated by external tension. It is formed by winding a plurality of layers (two layers in the figure) alternately or in long pitches in the same direction. Further, both of the carbon fiber reinforced layers 4.5 do not necessarily need to be carbon fiber reinforced layers, and it is sufficient if at least one layer is a carbon fiber reinforced layer.

The table below shows the results of comparing the weights of a conventional flexible composite tube 1 with an inner diameter of 100 mm and an outer diameter of 145 mm and a weight of 210 kg/c+M according to the present invention. According to this, it can be seen that the flexible composite pipe of the present invention can be significantly weighted.

Here, when the carbon fiber reinforcing layers 4 and 5 are composed of carbon fiber-reinforced plastic elongated bodies, the elongated bodies are made of, for example, 40% by weight of carbon fiber manufactured by Toshi ■ (trade name: Trading Card) and nylon 66 resin. obtained by melt dipping and extrusion molding.

In addition, in order to obtain optimal characteristics, carbon fibers may be blended with other fibers, or resin may be filled with inorganic substances or carbon particles. In addition to nylon resin, the resin is PEK.
(aromatic polyetherketone), PEEK (polyether polyetherketone), PES (polyether sulfone), PPS (polyphenylene sulfide), polyamide, polypropylene, etc. are used.

(Second Embodiment) This fluid transport pipe is the flexible composite pipe 1 shown in the first embodiment.
As shown in FIG. 2, a cylindrical insulating-side terminal fitting A and a conductive-side terminal fitting B are attached to both ends of the cylindrical terminal fitting. In Fig. 2, the cylindrical upper half and the symmetrical lower half of the insulating side terminal fitting A are omitted and only the upper half is shown in cross section, and the conductive side terminal fitting B shows the upper half in cross section. The flexible composite pipe 1 that extends between both end fittings A and B is schematically shown by a chain line.

To explain in more detail, one end 1 of the flexible composite pipe 1
In a, the terminal 2a of the metal interlock tube 2
An insulating side terminal fitting A is attached to insulate between the terminals 4a and 5a of the carbon fiber reinforcement N4 and 5, and a reinforcing layer abnormality detector 25 is installed between the terminals 2a and the terminals 4a to 5a.
is connected.

Furthermore, at the other end 1b of the flexible composite tube 1, the end 2b of the metal interlock tube 2 and the carbon fiber reinforcing layer 4 are connected to each other.
, 5 is attached with a conductive side terminal fitting B that electrically connects and establishes continuity between the terminals 4b and 5b of the terminals 4b and 5b.

The insulated end fitting A attached to one end 1a of the flexible composite pipe 1 is constructed as follows. That is, the metal interlock tube 2 at one end of the flexible composite tube 1
Insulating rings 8 and 9 are placed on the end edge 7 of the end 2a of the plastic tube 3 and the end 3a of the plastic tube 3, a metal end body 10 is fitted, and an annular packing 11 is fitted around the outer periphery of the end of the plastic tube 3.

This end body 10 has an inner diameter as an interface.

A recess 12, which is the same as the inner pipe 2, into which the end 2a of the interlock pipe 2, the end 3a of the plastic pipe 3, and the insulating rings 8, 9 are fitted, and a recess into which the annular packing 11 is fitted and pressed. 13, and the inner inner end surface 1
The annular packing II is pressed by the tip of the metal inner casing 16 fixed to the inner casing 16 with a fixing bolt 15 to press the outer peripheries of the end 2a of the interlock tube 2 and the end 3a of the plastic tube 3.

Connecting the inner casing 16 and the terminals 4a, 5a of the carbon fiber reinforcing layer 4.5 with a bond wire 17 to electrically connect the terminals 4a, 5a of the carbon fiber reinforcing layer 4.5 and the end body 10, A thermosetting resin insulator 18 is placed around each of the outer peripheries of the inner casing 16, the ends 4a and 5a of the carbon fiber reinforcing layer 4.5, and the end 6a of the outer sheath 6, and is screwed onto the outer peripheral surface of the end body 10. Outer casing I
An annular packing 21 is provided between the rear end portion 20 of the outer casing 9 and the outer peripheral surface of the outer sheath 6 to seal the inside of the outer casing 19. 22 is a flange portion at the tip of the end body 10.

A lead wire 23 is connected to the terminal 2a of the interlock tube 2 and pulled out to the outside, and a lead wire 24 is connected to the end body 1O, and a reinforcing layer abnormality detector 25 such as an ammeter is connected to both lead wires 23 and 24. Connect carbon fiber reinforcement N4,5
The terminals 4a, 5a of the interlock tube 2 and the terminal 2a of the interlock tube 2 are brought into conduction.

The conduction side end fitting B attached to the other end 1b of the flexible composite tube 1 is constructed as follows. That is, the ends 2b and 3b of the interlock tube 2 and the plastic tube 3 are fitted into the recess 27 at the inner depth of the metal end body 26, which has the same inner diameter as the metal interlock tube 2, and the inner diameter is the same as that of the metal interlock tube 2. Place the annular packing 29 in the recess 28 for holding the packing, and press the annular packing 29 with the tip of the metal inner casing 32 fixed to the inner end face 30 of the end body 26 with the stopper port 31 to release the interlock tube. 2 and the end 3b of the plastic tube 3.

The inner casing 32 and the carbon fiber reinforcing layers 4 and 5
The terminals 4b, 5b of the carbon fiber reinforcing layers 4, 5 are electrically connected to the end body 26 by connecting the ends 4b, 5b of the carbon fiber reinforcing layer 4. 5 and the terminal 6b of the outer sheath 6 are covered with a thermosetting resin insulator 34,
An annular packing 37 is provided between the rear end portion 36 of the outer casing 35 screwed onto the outer circumferential surface of the end body 26 and the outer circumferential surface of the terminal 6b of the outer sheath 6 to seal the inside of the outer casing 35. 38 is a flange portion at the tip of the end body 26.

A metal sleeve 3 is attached to the end 2b of the interlock tube 2.
One end of the sleeve 39 is welded to the end body 26, and the other end of the sleeve 39 is welded to the end body 26 to form the terminal 2b of the interlock tube 2.
By welding the ends 4b and 5b of the carbon fiber reinforcing layers 4 and 5 and the end 2b of the interlock tube 2 through the bond wire 33, the end body 26, and the sleeve 39, do.

2. By attaching the insulating end fitting A and the conductive end fitting B to both ends of the flexible composite pipe 1 as described above and connecting the reinforcing layer abnormality detector 25, the A circuit is formed in which the metal interlock tube 2 and the carbon fiber reinforcement layer 4.5 serve as a reciprocating electrical path, and this circuit connects the reinforcement layer abnormality detector 25 - the lead wire 23 on the insulated terminal fitting A side - the metal interface. Lock tube 2 - End body 26 on the conductive side terminal fitting B side - Bond wire 33 - Carbon fiber reinforcement layers 4, 5 - Bond wire 17 on the insulation side terminal fitting A side - Nindpodi 10 - Lead wire 24 - Reinforcement layer abnormality detector The circuit is formed by 25.

The resistance value of the interlock tube 2 when the entire length of the flexible composite tube 1 is intact and normal is R1, the resistance value of the carbon fiber reinforcing layers 4 and 5 is R2, and the resistance value at the insulated end fitting A is R3.
If the resistance value at the conductive side terminal fitting B is R4, the normal resistance value RO of the circuit in this normal state is RO=R1-I-R2+R3+R4. Therefore, this normal interlock tube 2, carbon fiber reinforcement layer 4,
When the circuit No. 5 is energized, the reinforcing layer abnormality detector 25 will indicate a predetermined current value in this normal state.

When the carbon fiber reinforcing layer 4.5 of the flexible composite pipe 1 deteriorates due to fatigue or is subjected to external trauma, the cross-sectional area decreases due to deformation, or damage or breakage occurs. When this occurs, the electrical resistance value of that portion changes from the normal value, and when the carbon fiber reinforcing layer 4.5 is completely cut, the resistance value becomes infinite.

In this way, when an abnormality occurs in the carbon fiber reinforcing layer 4.5 and its resistance value changes from the normal value R2, the reinforcing layer abnormality detector 25 such as an ammeter will give a different instruction from the normal one. become. Therefore, the fatigue deterioration of the carbon fiber reinforced N4.5 can be detected by the instruction from the detector 25. If it is detected that any of the carbon fiber reinforcing layers 4.5 has deteriorated due to fatigue, the flexible composite tube 1 is promptly replaced with a new one to maintain safety.

(Third Example) What is shown in Fig. 3 is a flexible composite pipe l with carbon fiber reinforcement N.
4 and 5 show insulating side terminal fittings A when a carbon fiber reinforced plastic elongated body 50 having a structure as shown in FIG. 4 is used. That is, the carbon fiber reinforced plastic elongated body 50 has a carbon fiber reinforced plastic core 51.
An insulating coating layer 52 made of polyethylene or the like is provided thereon.

Although not shown, this carbon fiber reinforced plastic elongated body 5
0 may be constructed by arranging carbon fibers densely in the center of the plastic and sparsely arranging them outward, instead of providing the insulating coating layer 52.

When the carbon fiber reinforced plastic elongated body 50 as described above is used, as shown in FIG. A part or all of the cores can be independently connected to a plurality of reinforcing layer abnormality detectors 25 via each lead wire 24 (insulated from the outer casing 19). It is desirable that all the carbon fiber reinforced plastic cores 51 be independently connected to the detector 25 via each lead wire 24.

Although the conductive side terminal fitting B is not shown, the carbon fiber reinforcing layer 4.
The carbon fiber reinforced plastic cores 5I at the terminals 4b and 5b of 5 are independently connected to the end body 2 via bond wires 33.
6 to connect the end body 26 and the terminal 2b of the interlock tube 2.

As a result, a plurality of circuits are formed in which the interlock tube 2 of the flexible composite tube 1, each carbon fiber reinforced plastic elongated body 5o, and each reinforcing layer abnormality detector 25 serve as electrical circuits.

The normal resistance value RO of each of the plurality of circuits is the second
As in the embodiment, RO=R1+R2+R3+R4.

Therefore, when the respective circuits are energized, the reinforcing layer abnormality detector 25
indicates a predetermined current value under normal conditions. If any of the carbon fiber reinforced plastic elongated bodies 50 constituting the carbon fiber reinforced layers 4 and 5 of the flexible composite pipe 1 is subjected to external trauma or fatigue deterioration, it will deform, resulting in a reduction in cross-sectional area or breakage. Live. At this time, the electrical resistance value of the abnormal carbon fiber-reinforced plastic elongated body 50 becomes larger than the normal value, and in the case of breakage, there is no continuity.

In this way, when an abnormality occurs in the carbon fiber reinforced plastic elongated body 50 and its resistance value changes from the normal resistance value R2,
The relevant reinforcing layer abnormality detector 25 such as an ammeter will give an instruction different from the instruction during normal times. In this way, when a circuit is formed for each of the carbon fiber reinforced plastic elongated bodies 50 or all of the elongated bodies 50, the number of broken carbon fiber reinforced plastic elongated bodies 50 can be observed, and the flexible It is preferable that the precursor state of the sexual complex tube I can be detected correctly and accurately before it causes serious destruction.

(Fourth Embodiment) This embodiment is a flexible structure in which a heating power supply device 42 as shown in FIG. 5 is connected in place of the reinforcing layer abnormality detector 25 in the fluid transport pipe shown in the second embodiment. It consists of a composite pipe 1, and the other configurations are the same as in the second embodiment.

When this heating power supply device 42 applies an appropriate current to the circuit formed by this, the metal interlock tube 2, and the carbon fiber reinforcing layers 4 and 5, the reinforcing layer 45 generates heat and separates from the fluid transport tube. Transport fluid can be heated or kept warm and transported without providing a heat insulating layer or heater.

〔Effect of the invention〕

As described above, since the present invention provides a carbon fiber reinforcing layer on the brass tink pipe, it is possible to significantly reduce the weight of the fluid transport pipe, and it is easy to manufacture, transport, and install, reducing costs, especially It is possible to reduce the cost of offshore oil production systems. Also, since the outer diameter of the transport pipe does not increase,
Even when this transport pipe is used in the ocean, it is less susceptible to the effects of waves, etc., and fatigue fractures due to repeated bending are reduced, resulting in a longer life. can be increased, and transportation costs can be reduced.

Furthermore, since carbon fiber is conductive, a metal interlock tube, a carbon fiber reinforcing layer, and a reinforcing layer abnormality detector form a circuit for detecting an abnormality in the reinforcing layer, thereby preventing deformation or damage of the reinforcing layer. It is possible to detect an abnormality in the reinforcing layer based on changes in electrical resistance due to abnormalities such as rupture, thereby preventing serious accidents in the fluid transport pipe and ensuring safety.

Furthermore, by providing a heating power supply device instead of the reinforcing layer abnormality detector and energizing the circuit, the transportation fluid can be heated or kept warm, and the high viscosity transportation fluid can be transported with a low viscosity. The cost of fluid transportation can be reduced.

[Brief explanation of drawings]

FIG. 1 is a partial sectional view showing the first embodiment of the present invention, FIG. 2 is a partial sectional view showing the second embodiment, and FIG. 3 is the third embodiment.
FIG. 4 is a sectional view showing an example of the carbon fiber reinforced plastic elongated body used in the third embodiment, and FIG. 5 is a sectional view showing the fourth embodiment of the present invention. 1: Flexible composite tube, 2: Interlock tube, 3 Niblast tube, 4.5 = carbon fiber reinforcement layer, 6: External sheath,
1a: one end of the flexible composite tube, 1b: the other end of the flexible composite tube, 2a, 2b: the ends of the interlock tube,
4a, 4b, 5a, 5b: Terminals of carbon fiber reinforcing layer, 25
: Reinforcement layer abnormality detector, 42: Heating power supply device, A: Insulating side terminal fitting, B: Conductive side terminal fitting.

Claims (3)

[Claims] (1) A plastic pipe is provided on top of the metal interlock pipe, a carbon fiber reinforcement layer is provided on the plastic pipe,
A fluid transport tube consisting of a flexible composite tube with an outer sheath over a carbon fiber reinforcement layer. (2) An insulating end fitting is attached to one end of the flexible composite tube to electrically insulate between the end of the interlock tube and the end of the carbon fiber reinforcing layer, and a reinforcing layer is placed between these two ends. An abnormality detector is connected to the other end of the flexible composite pipe, and a conduction side terminal fitting is attached to the other end of the flexible composite pipe to electrically connect and conduct between the end of the interlock pipe and the end of the carbon fiber reinforcing layer. The fluid transport pipe according to claim 1, comprising: (3) The fluid transport pipe according to claim 2, wherein a heating power supply device is connected in place of the reinforcing layer abnormality detector.