CN115433942B - Forced current cathodic protection system of composite continuous pipe conveying pipeline - Google Patents
Forced current cathodic protection system of composite continuous pipe conveying pipeline Download PDFInfo
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- CN115433942B CN115433942B CN202210895345.2A CN202210895345A CN115433942B CN 115433942 B CN115433942 B CN 115433942B CN 202210895345 A CN202210895345 A CN 202210895345A CN 115433942 B CN115433942 B CN 115433942B
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- 239000002131 composite material Substances 0.000 title claims abstract description 74
- 238000004210 cathodic protection Methods 0.000 title claims abstract description 14
- 239000010410 layer Substances 0.000 claims abstract description 49
- 239000002184 metal Substances 0.000 claims abstract description 34
- 229910052751 metal Inorganic materials 0.000 claims abstract description 34
- 230000003014 reinforcing effect Effects 0.000 claims abstract description 26
- 230000005540 biological transmission Effects 0.000 claims abstract description 10
- 239000011241 protective layer Substances 0.000 claims abstract description 8
- 229910000831 Steel Inorganic materials 0.000 claims description 11
- 239000010959 steel Substances 0.000 claims description 11
- 235000017166 Bambusa arundinacea Nutrition 0.000 claims description 4
- 235000017491 Bambusa tulda Nutrition 0.000 claims description 4
- 241001330002 Bambuseae Species 0.000 claims description 4
- 235000015334 Phyllostachys viridis Nutrition 0.000 claims description 4
- 239000011425 bamboo Substances 0.000 claims description 4
- 229920013716 polyethylene resin Polymers 0.000 claims description 4
- 238000005260 corrosion Methods 0.000 abstract description 21
- 230000007797 corrosion Effects 0.000 abstract description 19
- 210000001503 joint Anatomy 0.000 abstract description 7
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 abstract description 6
- 230000002378 acidificating effect Effects 0.000 abstract description 3
- 239000003345 natural gas Substances 0.000 abstract description 3
- 230000032683 aging Effects 0.000 abstract description 2
- 239000003209 petroleum derivative Substances 0.000 abstract description 2
- 238000000034 method Methods 0.000 description 10
- 238000004364 calculation method Methods 0.000 description 7
- 239000004033 plastic Substances 0.000 description 7
- 229920003023 plastic Polymers 0.000 description 7
- 239000007789 gas Substances 0.000 description 5
- 239000003921 oil Substances 0.000 description 5
- 238000010276 construction Methods 0.000 description 4
- 239000000463 material Substances 0.000 description 4
- 230000002787 reinforcement Effects 0.000 description 4
- 229920001169 thermoplastic Polymers 0.000 description 4
- 239000004416 thermosoftening plastic Substances 0.000 description 4
- 230000007547 defect Effects 0.000 description 3
- 238000009933 burial Methods 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 230000007613 environmental effect Effects 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 230000007704 transition Effects 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 229910000975 Carbon steel Inorganic materials 0.000 description 1
- 229910001018 Cast iron Inorganic materials 0.000 description 1
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 238000005452 bending Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000010962 carbon steel Substances 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 239000000571 coke Substances 0.000 description 1
- 239000004020 conductor Substances 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000004880 explosion Methods 0.000 description 1
- 239000000945 filler Substances 0.000 description 1
- 239000003112 inhibitor Substances 0.000 description 1
- 230000002401 inhibitory effect Effects 0.000 description 1
- 230000000670 limiting effect Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 230000002829 reductive effect Effects 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- 150000003384 small molecules Chemical class 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 229920005992 thermoplastic resin Polymers 0.000 description 1
- 238000003466 welding Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23F—NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25
- C23F13/00—Inhibiting corrosion of metals by anodic or cathodic protection
- C23F13/02—Inhibiting corrosion of metals by anodic or cathodic protection cathodic; Selection of conditions, parameters or procedures for cathodic protection, e.g. of electrical conditions
- C23F13/06—Constructional parts, or assemblies of cathodic-protection apparatus
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23F—NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25
- C23F13/00—Inhibiting corrosion of metals by anodic or cathodic protection
- C23F13/02—Inhibiting corrosion of metals by anodic or cathodic protection cathodic; Selection of conditions, parameters or procedures for cathodic protection, e.g. of electrical conditions
- C23F13/06—Constructional parts, or assemblies of cathodic-protection apparatus
- C23F13/08—Electrodes specially adapted for inhibiting corrosion by cathodic protection; Manufacture thereof; Conducting electric current thereto
- C23F13/20—Conducting electric current to electrodes
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23F—NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25
- C23F13/00—Inhibiting corrosion of metals by anodic or cathodic protection
- C23F13/02—Inhibiting corrosion of metals by anodic or cathodic protection cathodic; Selection of conditions, parameters or procedures for cathodic protection, e.g. of electrical conditions
- C23F13/06—Constructional parts, or assemblies of cathodic-protection apparatus
- C23F13/08—Electrodes specially adapted for inhibiting corrosion by cathodic protection; Manufacture thereof; Conducting electric current thereto
- C23F13/22—Monitoring arrangements therefor
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
- F16L58/00—Protection of pipes or pipe fittings against corrosion or incrustation
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F17—STORING OR DISTRIBUTING GASES OR LIQUIDS
- F17D—PIPE-LINE SYSTEMS; PIPE-LINES
- F17D5/00—Protection or supervision of installations
- F17D5/005—Protection or supervision of installations of gas pipelines, e.g. alarm
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23F—NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25
- C23F2213/00—Aspects of inhibiting corrosion of metals by anodic or cathodic protection
- C23F2213/30—Anodic or cathodic protection specially adapted for a specific object
- C23F2213/32—Pipes
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Mechanical Engineering (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- General Engineering & Computer Science (AREA)
- Prevention Of Electric Corrosion (AREA)
Abstract
The invention relates to the technical field of corrosion protection of petroleum and natural gas conveying pipelines, in particular to a forced current cathode protection system of a composite continuous pipe conveying pipeline, which comprises at least one protection unit, wherein the protection unit comprises a continuous pipe unit, a potentiostat and an auxiliary anode; the coiled tubing unit comprises a plurality of composite coiled tubing connected in series by a joint assembly; the composite continuous pipe comprises a transmission layer, a metal reinforcing layer and a protective layer which are sequentially arranged from inside to outside; the joint component comprises an intermediate joint, a joint outer sleeve and a joint core pipe; a wire channel is arranged on the middle joint, wires are arranged in the wire channel, and the metal reinforcing layers of the adjacent composite continuous pipes are connected through the wires; the potentiostat is respectively connected with the auxiliary anode and the metal reinforcing layer. The invention realizes the forced current cathodic protection of the composite continuous pipe conveying pipeline, avoids the corrosion and aging of the metal reinforcing layer in the wet and hot acidic environment, and achieves the purpose of prolonging the service life of the pipeline.
Description
Technical Field
The invention relates to the technical field of corrosion protection of petroleum and natural gas conveying pipelines, in particular to a forced current cathode protection system of a steel skeleton reinforced thermoplastic composite continuous pipe.
Background
The steel skeleton reinforced thermoplastic composite continuous pipe has a series of advantages of corrosion resistance, single length, easy bending, light weight, high ring stiffness, convenient transportation and construction and the like, is gradually favored by oilfield users, becomes a substitute product of metal carbon steel pipes, and is an important component for selecting materials for oil and gas field pipelines at home and abroad. According to SY/T6662.4-2014 non-metallic composite pipe for oil and gas industry part 4: the steel skeleton reinforced thermoplastic composite continuous pipe (composite continuous pipe for short) generally comprises a transmission layer, a metal reinforcing layer and a protection layer which are arranged from inside to outside, wherein the transmission layer is usually made of polyethylene resin, and other types of thermoplastic resins can be adopted; the metal reinforcing layer adopts high-strength steel wires with braided structures or high-strength steel belts; the protective layer is made of polyethylene resin.
The length of a single composite coiled tubing is typically about 300 meters and a plurality of composite coiled tubing are connected by a joint assembly to form a transfer line of a desired length. CN211118213U discloses a plastic composite pipe joint, which comprises a joint body, wherein a joint jacket is fixedly connected to the outside of one end of the joint body, a cavity for accommodating a plastic composite pipe is formed between the joint jacket and the joint body, and the plastic composite pipe comprises a plastic composite pipe outer protection layer, a plastic composite pipe metal reinforcing layer and a plastic composite pipe base layer which are sequentially arranged from outside to inside; the outer wall of the cavity inner joint body and the inner wall of the joint outer sleeve are respectively provided with a plurality of tooth blocks for clamping and fixing the plastic composite pipe.
When the composite continuous pipe is used for conveying high gas-oil ratio or natural gas medium, water vapor and CO 2 、H 2 S gas molecules gather in annular spaces of a transmission layer and a protective layer of the composite continuous pipe through permeation to form an acidic corrosion environment, and induce corrosion of the surface of a metal reinforcing layer material of the composite continuous pipe, so that the strength of the metal reinforcing layer is reduced, and the continuous pipe is inevitably subjected to pipe explosion failure under the action of oil gas gathering and transportation internal pressure along with the extension of the service time of a pipelineProblems.
The control method of pipeline corrosion adopts a corresponding corrosion control method according to different corrosion mechanisms and different environmental conditions, and the most widely applied methods for controlling metal corrosion in the oil and gas pipeline protection process are as follows: 1. selecting a corrosion-resistant material; 2. controlling the corrosion environment; 3. selecting an effective anti-corrosion layer; 4. cathode protection; 5. and adding a corrosion inhibitor. Among these, the application of an anticorrosive layer (also called a cover layer) to a metal surface is a physical protection method that isolates the metal from the corrosive medium by insulating treatment of the metal surface. This method of corrosion protection is effective, but is not possible to achieve absolute reliability in practical engineering. This is because none of the insulating coating materials is completely impermeable to small molecules such as water, oxygen, etc.; at the same time, mass transfer between the interface of the steel and the corrosion-resistant insulating layer is also unavoidable. Furthermore, the corrosion-resistant insulating layer on the metal surface is unlikely to be free from defects in construction production and in transportation and storage. The forced current cathodic protection has the advantages of continuously adjustable output current, large protection range, no limit of environmental resistivity, long service life of the protection device and the like, and can make up the defect of an anti-corrosion layer and positively intervene in corrosion reaction, thereby more thoroughly inhibiting the occurrence of the corrosion reaction. However, for composite continuous pipe conveying pipelines, no effective cathodic protection method exists at present, because the metal reinforcing layers of the composite continuous pipes in adjacent sections are not conductive, and therefore, only one set of forced current cathodic protection system can be arranged for each composite continuous pipe, which leads to complex construction and high cost.
Disclosure of Invention
The invention aims to solve the defects in the prior art and provide a forced current cathode protection system of a composite continuous pipe conveying pipeline, wherein a wire is arranged in a wire channel of an intermediate joint, and metal reinforcing layers of adjacent composite continuous pipes are connected through the wire, so that the forced current cathode protection length of the composite continuous pipes is selected according to requirements, and the forced current cathode protection of the composite continuous pipe conveying pipeline is realized.
The technical problems to be solved are realized by adopting the following technical scheme: the forced current cathodic protection system of the composite continuous pipe conveying pipeline comprises at least one protection unit, wherein the protection unit comprises a continuous pipe unit, a potentiostat and an auxiliary anode; the coiled tubing unit comprises a plurality of composite coiled tubing connected in series by a joint assembly; the composite continuous pipe comprises a transmission layer, a metal reinforcing layer and a protective layer which are sequentially arranged from inside to outside; the joint assembly comprises an intermediate joint, a joint outer sleeve and a joint core pipe, wherein the intermediate joint and the joint outer sleeve are sleeved outside the joint core pipe, the joint outer sleeve is connected to two ends of the intermediate joint, an annular space is formed between the joint outer sleeve and the joint core pipe, and the composite continuous pipe is inserted into the annular space; the middle joint is provided with a wire channel, wires are arranged in the wire channel, and the adjacent metal reinforcing layers of the composite continuous pipes are connected through the wires; the potentiostat is connected with the auxiliary anode through an anode wire, and is connected with the metal reinforcing layer of the composite continuous pipe through a cathode wire.
Compared with the prior art, the forced current cathodic protection system of the composite continuous pipe conveying pipeline has the beneficial effects that: the lead is arranged in the lead channel of the intermediate joint, and the metal reinforcing layers of the adjacent composite continuous pipes are connected through the lead, so that the length of the protection unit can be selected according to the requirements, the method has the advantages of small construction amount and low cost, and the mutual interference caused by the too small distance of the forced current cathode protection system can be prevented, thereby realizing the forced current cathode protection of the composite continuous pipe conveying pipeline, avoiding the corrosion and aging of the metal reinforcing layers in a wet and hot acidic environment, and achieving the purpose of prolonging the service life of the pipeline.
According to the technical scheme, the joint outer sleeve is welded and fixed with the middle joint, and the joint core tube is welded and fixed with the middle joint.
The technical scheme of the invention is that the protection unit further comprises end joints and insulating flanges, wherein the end joints are arranged at two ends of the continuous pipe unit, each end joint comprises a connecting flange, an end joint core pipe and an end joint outer sleeve, each end joint core pipe and each end joint outer sleeve are fixedly connected with the connecting flange, each end joint outer sleeve is sleeved outside each end joint core pipe, an end annular space is formed between each end joint outer sleeve and each end joint core pipe, and the composite continuous pipe positioned at two ends of the continuous pipe unit is inserted into the end annular space; the insulating flange is connected with the connecting flange; the metal reinforcing layer of the composite continuous pipe positioned at the end part of the continuous pipe unit is connected with the end joint core pipe through an end wire, and the potentiostat is connected with the end joint through a cathode wire; adjacent continuous pipe units are connected through insulating flanges.
The technical scheme of the invention is that bamboo joint inverted teeth for fixing the composite continuous pipe are arranged on the inner wall of the joint outer sleeve, the outer wall of the joint core pipe, the outer wall of the end joint core pipe and the inner wall of the end joint outer sleeve.
Drawings
FIG. 1 is a schematic structural view of a composite continuous pipe in example 1.
Fig. 2 is a schematic structural view of the composite coiled tubing of example 1 connected by a joint assembly.
Fig. 3 is a schematic structural diagram of the forced current cathodic protection system of the composite continuous pipe transfer line of example 1.
FIG. 4 is a graph showing the interference factor of the anode bed consisting of n auxiliary anodes in example 1 versus the auxiliary anode spacing.
In the figure: 1. the potentiostat comprises a potentiostat body, wherein the potentiostat body comprises 2 parts of an auxiliary anode, 3 parts of a transmission layer, 4 parts of a metal reinforcing layer, 5 parts of a protective layer, 6 parts of an intermediate joint, 7 parts of a joint outer sleeve, 8 parts of a joint core tube, 9 parts of a wire, 10 parts of an anode wire, 11 parts of a cathode wire, 12 parts of a bamboo joint inverted tooth, 13 parts of an insulating flange, 14 parts of a connecting flange, 15 parts of an end joint core tube, 16 parts of an end joint outer sleeve, 17 parts of an end joint wire.
Detailed Description
In order to make the objects, technical solutions and advantages of the technical solutions of the present disclosure more clear, the technical solutions of the embodiments of the present disclosure will be clearly and completely described below with reference to the accompanying drawings of specific embodiments of the present disclosure. Like reference numerals in the drawings denote like parts. It should be noted that the described embodiments are some, but not all embodiments of the present disclosure. All other embodiments, which can be made by one of ordinary skill in the art without the need for inventive faculty, are within the scope of the present disclosure, based on the described embodiments of the present disclosure.
Unless defined otherwise, technical or scientific terms used herein should be given the ordinary meaning as understood by one of ordinary skill in the art to which this disclosure belongs. The terms "first," "second," and the like in the description and in the claims, do not denote any order, quantity, or importance, but rather are used to distinguish one element from another. Likewise, the terms "a" or "an" and the like do not necessarily denote a limitation of quantity. The word "comprising" or "comprises", and the like, means that elements or items preceding the word are included in the element or item listed after the word and equivalents thereof, but does not exclude other elements or items. The terms "connected" or "connected," and the like, are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "upper", "lower", "left", "right", etc. are used merely to indicate relative positional relationships, which may also be changed when the absolute position of the object to be described is changed.
Example 1
Fig. 1 to 4 show embodiment 1 of the present invention.
The embodiment provides a forced current cathodic protection system of a composite continuous pipe conveying pipeline, which comprises at least one protection unit, wherein the protection unit comprises a continuous pipe unit, a potentiostat 1 and an auxiliary anode 2.
The coiled tubing unit comprises ten composite coiled tubing units connected in series by a joint assembly, each composite coiled tubing unit having a length of about 300 meters and a length of about 3.0km.
The composite continuous pipe is a steel skeleton reinforced thermoplastic composite continuous pipe, as shown in fig. 1, the composite continuous pipe comprises a transmission layer 3, a metal reinforcing layer 4 and a protective layer 5 which are sequentially arranged from inside to outside, the transmission layer 3 and the protective layer 5 are made of polyethylene resin, and the reinforcing layer 4 is made of high-strength steel wires with a braided structure.
In this example, the diameter of the composite coiled tubing was 150mm and the engineering pressure was 5.5MPa.
As shown in fig. 2, the joint assembly comprises an intermediate joint 6, a joint outer sleeve 7 and a joint core tube 8, wherein the intermediate joint 6 and the joint outer sleeve 7 are sleeved outside the joint core tube 8, the joint core tube 8 is welded and fixed with the intermediate joint 6, the joint outer sleeve 7 is connected to two ends of the intermediate joint 6 through welding, an annulus is formed between the joint outer sleeve 7 and the joint core tube 8, and the composite continuous tube is inserted into the annulus.
The middle joint 6 is provided with a wire channel, a wire 9 is arranged in the wire channel, and the adjacent metal reinforcing layers 4 of the composite continuous pipes are connected through the wire 9.
As shown in fig. 2, the two ends of the continuous pipe unit are each provided with an end fitting and an insulating flange 13. The end connector comprises a connecting flange 14, an end connector core tube 15 and an end connector outer sleeve 16, wherein the end connector core tube 15 and the end connector outer sleeve 16 are fixedly connected with the connecting flange 14, the end connector outer sleeve 16 is sleeved outside the end connector core tube 15, an end annular space is formed between the end connector outer sleeve 16 and the end connector core tube 15, and the composite continuous pipes at the two ends of the continuous pipe units are inserted into the end annular space. The insulating flange 13 is connected to the connecting flange 14. The metal reinforcement layer 4 of the composite coiled tubing at the end of the coiled tubing unit is connected to an end connector core tube 15 by an end conductor 17. Adjacent ones of the coiled tubing units are connected by insulating flanges 13.
As shown in fig. 3, the potentiostat 1 is connected to the auxiliary anode 2 via an anode lead 10, and the potentiostat 1 is connected to the continuous tube unit via a cathode lead 11. Specifically, the potentiostat 1 is connected to an end fitting by a cathode lead 11.
The inner wall of the joint outer sleeve 7. The outer wall of the joint core tube 8, the outer wall of the end joint core tube 15 and the inner wall of the end joint jacket 16 are all provided with bamboo joint inverted teeth 12 for fixing the composite continuous tube.
The auxiliary anode 2 adopts a high silicon cast iron anode (vertical type), the length is 1.5m, the diameter is 0.05m, and the burial depth (the top of the filler is 1.5m from the ground surface).
In the embodiment, the design service life of the composite continuous pipe is longer than 20 years, the minimum protection potential is-0.85V (CSE), the maximum protection potential is-1.15V (CSE), the resistivity is 0.224 Ω & mm2/m, the current density is 8 mu A/m2, the annulus damp-heat environment resistivity is 50 Ω & m in the service process of the composite continuous pipe, and the calculation method of the forced current is as follows:
(1) Calculating the protection length of the composite continuous pipe:
wherein:
L p -single-sided protection pipe length in meters (m);
DeltaV, the difference between the limiting protection potential and the protection potential in volts (V);
D p -the outer diameter of the metal reinforcement layer in meters (m);
J s protection current density in amperes per square meter (A/m 2 )；
R s -a pipeline line resistance in ohms per meter (Ω/m);
ρ τ the resistivity of the steel tube is measured in European square millimeters per meter (omega. Mm) 2 /m)；
Delta-pipe wall thickness in millimeters (mm);
(2) Calculation of protection current
2I o ＝2π×D p ×J s ×L p 3
Wherein:
I o -unilateral pipe protection current in amperes (a);
D p -the outer diameter of the pipe in meters (m);
J s protection current density in amperes per square meter (A/m 2 )；
L p -single-sided protection pipe length in meters (m);
(3) Calculation of auxiliary anode ground resistance:
(1) the calculation of the single vertical auxiliary anode grounding resistance is shown in a formula 4, the calculation of the single horizontal auxiliary anode grounding resistance is shown in a formula 5, the calculation of the deep well auxiliary anode grounding resistance is shown in a formula 6,
wherein:
R v1 -single vertical auxiliary anode ground resistance in euro (Ω);
R v2 -a deeply buried auxiliary anode ground resistance in ohms (Ω);
R h -single horizontal auxiliary anode ground resistance in euro (Ω);
ρ—the specific electrical resistance of the hot and humid environment in the annulus in the units of omega-meters (Ω·m), ρ in this example being 50Ω·m;
L a -auxiliary anode length in meters (m);
D a -auxiliary anode diameter in meters (m);
t-the burial depth of the auxiliary anode, wherein the unit is meter (m);
(2) calculation of auxiliary anode ground resistance:
wherein:
R z -an auxiliary anode ground resistance in ohms (Ω);
f—auxiliary anode resistance correction coefficient, see fig. 4;
R a -single auxiliary anode ground resistance in ohms (Ω);
n-anode count;
ρ—the annulus wet heat environment resistivity in omega-m;
s-auxiliary anode spacing in meters (m);
(4) And (3) calculating the mass of the auxiliary anode:
wherein:
W a -the total mass of the auxiliary anode in kilograms (kg);
T a -auxiliary anode design life in years (a);
ω a consumption rate of auxiliary anode in kg per year [ kg/(A. A)]；
I-protection current in amperes (a);
k is the auxiliary anode utilization coefficient, and 0.7 to 0.85 is taken;
(5) Calculating power of the power supply equipment:
V＝I(R z +R l +R c )+V τ 11. The method of the invention
I＝2I o 14, of the order of magnitude
Wherein:
p-mains power in watts (W);
i-protection current in amperes (A);
v-the output voltage of the power supply device, in volts (V);
η—power supply device efficiency, η=0.7 in this embodiment;
R z -an auxiliary anode ground resistance in ohms (Ω);
R l -wire resistance in ohms (Ω);
R c -cathodic transition resistance in ohms (Ω);
V τ -back electromotive force of auxiliary anode bed in V (V), when filled with coke, V is taken τ ＝2V；
R t -a transition resistance of the anti-corrosive layer in omega-m;
r t -metal reinforcement line resistance in ohms per meter (Ω/m);
alpha-metal reinforcement attenuation factor in units of (m -1 )；
L is the length of the protected pipeline, and the unit is meter (m);
I o -unilateral protection current in amperes (a).
According to the calculated protection current of the composite continuous pipe conveying pipeline, the protection current is 0.12A, the grounding resistance of the auxiliary anode 2 is 42.0 omega, the mass of the auxiliary anode 2 is 1.5kg, and the power of the power supply equipment of the potentiostat 1 is 20V/10A.
The foregoing is merely a specific implementation of the disclosure, but the scope of the embodiments of the disclosure is not limited thereto, and any person skilled in the art may easily think of changes, substitutions or combinations within the technical scope of the embodiments of the disclosure or under the ideas of the embodiments of the disclosure, and all fall within the scope of the embodiments of the disclosure.
Claims (4)
1. The forced current cathodic protection system of the composite continuous pipe conveying pipeline is characterized by comprising at least one protection unit, wherein the protection unit comprises a continuous pipe unit, a potentiostat (1) and an auxiliary anode (2); the coiled tubing unit comprises a plurality of composite coiled tubing connected in series by a joint assembly; the composite continuous pipe comprises a transmission layer (3), a metal reinforcing layer (4) and a protective layer (5) which are sequentially arranged from inside to outside; the joint assembly comprises an intermediate joint (6), a joint outer sleeve (7) and a joint core tube (8), wherein the intermediate joint (6) and the joint outer sleeve (7) are sleeved outside the joint core tube (8), the joint outer sleeve (7) is connected to two ends of the intermediate joint (6), an annular space is formed between the joint outer sleeve (7) and the joint core tube (8), and the composite continuous tube is inserted into the annular space; a wire channel is arranged on the intermediate joint (6), a wire (9) is arranged in the wire channel, and the adjacent metal reinforcing layers (4) of the composite continuous pipes are connected through the wire (9); the potentiostat (1) is connected with the auxiliary anode (2) through an anode lead (10), and the potentiostat (1) is connected with the metal reinforcing layer (4) of the composite continuous pipe through a cathode lead (11);
the protection unit further comprises end joints and insulating flanges (13), wherein the end joints are arranged at two ends of the continuous pipe unit, each end joint comprises a connecting flange (14), an end joint core pipe (15) and an end joint outer sleeve (16), each end joint core pipe (15) and each end joint outer sleeve (16) are fixedly connected with the corresponding connecting flange (14), each end joint outer sleeve (16) is sleeved outside each end joint core pipe (15), an end annular space is formed between each end joint outer sleeve (16) and each end joint core pipe (15), and the composite continuous pipe at two ends of the continuous pipe unit is inserted into the corresponding end annular space; the insulating flange (13) is connected with the connecting flange (14); the metal reinforcing layer (4) of the composite continuous pipe positioned at the end part of the continuous pipe unit is connected with an end joint core pipe (15) through an end lead (17), and the potentiostat (1) is connected with an end joint through a cathode lead (11); adjacent continuous pipe units are connected by insulating flanges (13).
2. The forced current cathodic protection system of a composite continuous pipe transfer line of claim 1 wherein said joint outer jacket (7) is welded to said intermediate joint (6) and said joint core tube (8) is welded to said intermediate joint (6).
3. The forced current cathodic protection system of a composite continuous pipe transfer line of claim 1 wherein said inner wall of said joint jacket (7), said outer wall of said joint core tube (8), said outer wall of said end joint core tube (15), and said inner wall of said end joint jacket (16) are each provided with a bamboo joint inverted tooth (12) for fixing the composite continuous pipe.
4. A forced current cathodic protection system for a composite continuous pipe conveying pipeline according to any one of claims 1 to 3, wherein said transmission layer (3) and said protection layer (5) are made of polyethylene resin, and said reinforcing layer (4) is made of high-strength steel wire or high-strength steel belt of braided structure.
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Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101397671A (en) * | 2007-09-30 | 2009-04-01 | 濮阳市信宇石油机械化工有限公司 | Sacrificial anode and protective cathode-oil pipe anti-corrosive apparatus |
| JP2010001549A (en) * | 2008-06-23 | 2010-01-07 | Tokyo Gas Co Ltd | Cathodic corrosion protection system and cathodic corrosion protection method for underground pipeline |
| CN101962777A (en) * | 2010-10-15 | 2011-02-02 | 吴发东 | Cathode protecting system for preventing cathode from being shielded |
| JP2012087351A (en) * | 2010-10-18 | 2012-05-10 | Tokyo Gas Co Ltd | Cathodic protection method and cathodic protection system of buried metal pipeline |
| CN103243335A (en) * | 2013-05-23 | 2013-08-14 | 中煤科工集团武汉设计研究院 | Impressed current cathodic protection method for long-distance pipeline coal transporting |
| CN204251715U (en) * | 2014-12-08 | 2015-04-08 | 新疆坤源石油技术开发有限公司 | Oil tube cathode protector |
| CN206486600U (en) * | 2017-02-27 | 2017-09-12 | 中国石油天然气集团公司 | A kind of cathode protection device applied to shield water seal tunnel |
| CN207435552U (en) * | 2017-11-20 | 2018-06-01 | 中国能源建设集团广东省电力设计研究院有限公司 | The combined system of direct current grounding pole and buried metal pipeline |
| CN208038556U (en) * | 2018-04-13 | 2018-11-02 | 新疆奥睿博节能科技发展有限公司 | A kind of oil tube cathode protector |
| CN111926335A (en) * | 2020-08-18 | 2020-11-13 | 中国石油化工股份有限公司 | Pipeline cathode protection system and method |
-
2022
- 2022-07-26 CN CN202210895345.2A patent/CN115433942B/en active Active
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101397671A (en) * | 2007-09-30 | 2009-04-01 | 濮阳市信宇石油机械化工有限公司 | Sacrificial anode and protective cathode-oil pipe anti-corrosive apparatus |
| JP2010001549A (en) * | 2008-06-23 | 2010-01-07 | Tokyo Gas Co Ltd | Cathodic corrosion protection system and cathodic corrosion protection method for underground pipeline |
| CN101962777A (en) * | 2010-10-15 | 2011-02-02 | 吴发东 | Cathode protecting system for preventing cathode from being shielded |
| JP2012087351A (en) * | 2010-10-18 | 2012-05-10 | Tokyo Gas Co Ltd | Cathodic protection method and cathodic protection system of buried metal pipeline |
| CN103243335A (en) * | 2013-05-23 | 2013-08-14 | 中煤科工集团武汉设计研究院 | Impressed current cathodic protection method for long-distance pipeline coal transporting |
| CN204251715U (en) * | 2014-12-08 | 2015-04-08 | 新疆坤源石油技术开发有限公司 | Oil tube cathode protector |
| CN206486600U (en) * | 2017-02-27 | 2017-09-12 | 中国石油天然气集团公司 | A kind of cathode protection device applied to shield water seal tunnel |
| CN207435552U (en) * | 2017-11-20 | 2018-06-01 | 中国能源建设集团广东省电力设计研究院有限公司 | The combined system of direct current grounding pole and buried metal pipeline |
| CN208038556U (en) * | 2018-04-13 | 2018-11-02 | 新疆奥睿博节能科技发展有限公司 | A kind of oil tube cathode protector |
| CN111926335A (en) * | 2020-08-18 | 2020-11-13 | 中国石油化工股份有限公司 | Pipeline cathode protection system and method |
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| CN115433942A (en) | 2022-12-06 |
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Address after: 226000 Room 101, Building 9, No. 9, Zhongxiu East Road, Chongchuan District, Nantong, Jiangsu Patentee after: Jiangsu Zhengdao Marine Technology Co.,Ltd. Country or region after: China Address before: 226007 plant 5, No. 9, Zhongxiu East Road, Chongchuan District, Nantong City, Jiangsu Province Patentee before: Jiangsu Zhengdao Marine Technology Co.,Ltd. Country or region before: China |