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CN-121992413-A - Corrosion-resistant protection device and method for inner wall of metal pipeline of oilfield station

CN121992413ACN 121992413 ACN121992413 ACN 121992413ACN-121992413-A

Abstract

The invention discloses an anti-corrosion protection device and a protection method for the inner wall of a metal pipeline of an oil field station, which belong to the technical field of oil and gas field corrosion and protection, wherein the protection device comprises a metal pipe body communicated with the protected metal pipeline of the oil field station, a metal net cage is arranged in the metal pipe body, a sacrificial anode layer is cast on the inner surface of the metal pipe body, the metal net cage is wrapped in the sacrificial anode layer, and the metal pipe body is respectively connected with the metal net cage and the sacrificial anode layer in a conductive manner; the device is connected with the protected metal pipeline in a conductive way, and protects the protected metal pipeline by the sacrificial anode and cathode protection principle, the invention effectively solves the technical problems of unstable corrosion prevention effect and high corrosion prevention cost of the inner wall of the oilfield station pipeline, and has the advantages of stable corrosion prevention effect, simple and compact structure and low operation and maintenance cost.

Inventors

  • GUO LIANG
  • ZHANG YUCHEN
  • YANG XIAOFENG
  • DENG LIANGGUANG
  • LU XIAO
  • DU HONGMEI
  • LEI HAORAN
  • LIANG ZAIDONG
  • WU PENGFEI
  • ZHANG XINRAN

Assignees

  • 中国石油天然气集团有限公司
  • 中国石油集团川庆钻探工程有限公司

Dates

Publication Date
20260508
Application Date
20241105

Claims (10)

  1. 1. The corrosion-resistant protection device for the inner wall of the metal pipeline of the oilfield station is characterized by comprising a metal pipe body (1) communicated with the protected metal pipeline of the oilfield station, wherein a metal net cage (3) is arranged in the metal pipe body (1), a sacrificial anode layer (2) is cast on the inner surface of the metal pipe body (1), the metal net cage (3) is wrapped in the sacrificial anode layer (2), the metal pipe body (1) is respectively in conductive connection with the metal net cage (3) and the sacrificial anode layer (2), and the corrosion-resistant protection device is in conductive connection with the protected metal pipeline and protects the protected metal pipeline through a sacrificial anode cathode protection principle.
  2. 2. The corrosion protection device for the inner wall of a metal pipeline of an oilfield station is characterized in that a plurality of conductive contact strips (7) are arranged on the outer surface of the metal mesh cage (3), the end parts of the conductive contact strips (7) are clung to the inner surface of the metal pipe body (1), and the metal mesh cage (3) and the conductive contact strips (7) are wrapped in the sacrificial anode layer (2).
  3. 3. The corrosion protection device for the inner wall of a metal pipeline of an oilfield station as claimed in claim 2, wherein the sacrificial anode layer (2) is made of any one of aluminum alloy and zinc alloy, the thickness of the sacrificial anode layer (2) wrapped on the metal net cage (3) is D1, and D1 is more than or equal to 10mm.
  4. 4. The corrosion protection device for the inner wall of a metal pipeline of an oilfield station as claimed in claim 3, wherein the lengths of the metal mesh cage (3) and the metal pipe body (1) are equal and smaller than the length of the sacrificial anode layer (2), the two ends of the sacrificial anode layer (2) and the metal mesh cage (3) are in a bell mouth structure, and the two ends of the sacrificial anode layer (2) are respectively wrapped at the two ends of the metal pipe body (1) and the metal mesh cage (3).
  5. 5. The corrosion protection device for the inner wall of a metal pipeline of an oilfield station as claimed in claim 4, wherein the two ends of the metal pipe body (1) are respectively fixed with a metal pipe flange (4) for detachably connecting with the protected metal pipeline.
  6. 6. The corrosion protection device for the inner wall of a metal pipeline of an oilfield station as claimed in claim 5, wherein the metal pipe flange (4) is fixedly provided with a conductive sealing gasket (5).
  7. 7. The corrosion protection device for the inner wall of a metal pipeline of an oilfield station as claimed in claim 6, wherein the inner diameter of the metal pipe body (1) is larger than the inner diameter of the protected metal pipeline, and the difference value between the inner diameters of the metal pipe body (1) and the protected metal pipeline is more than or equal to 20mm.
  8. 8. The corrosion protection device for the inner wall of a metal pipeline of an oilfield station as defined in claim 7, wherein the self-corrosion potential of the material of the metal net cage (3) is lower than that of the material of the metal pipeline to be protected.
  9. 9. The corrosion protection device for the inner wall of a metal pipeline of an oilfield station as claimed in claim 7, wherein the metal net cage (3) is made of the same material as the metal pipeline to be protected.
  10. 10. A method of protecting an oilfield yard metal line inner wall corrosion protection device according to any one of claims 1-9, comprising the steps of: s1, connecting a metal pipe body (1) to a protected metal pipeline, so that the metal pipe body (1) becomes a component part of a fluid transmission pipeline of an oilfield station; S2, when a corrosive medium flows through the sacrificial anode layer (2) cast on the inner surface of the metal pipe body (1), activating the sacrificial anode layer (2) to enable the sacrificial anode layer (2) to be electrochemically dissolved and release electrons; S3, electrons released by dissolution of the sacrificial anode layer (2) are conducted to the inner wall of the protected metal pipeline through the metal net cage (3) and the metal pipe body (1), so that the inner wall of the protected metal pipeline is in an electron excess state; And S4, maintaining each point of the inner wall of the protected metal pipeline at the same negative potential through the electron excess state of the inner wall of the protected metal pipeline, and providing continuous protection current through the continuous released electrons of the sacrificial anode layer (2), so that the inner wall of the protected metal pipeline keeps the negative potential for a long time, and forming the cathode protection of the inner wall of the protected metal pipeline for corrosion prevention.

Description

Corrosion-resistant protection device and method for inner wall of metal pipeline of oilfield station Technical Field The invention belongs to the technical field of corrosion and protection of oil and gas fields, and particularly relates to an anti-corrosion protection device for an inner wall of a metal pipeline of an oil field station. Background The oil field stations such as gathering and conveying stations are the summary of the produced liquid of each single well, the water content continuously rises along with the development of oil field blocks and enters the later development period, and the phenomena of corrosion and scaling are aggravated, because the inner wall of the metal pipeline is in direct contact with the conveying medium, and a plurality of conveying mediums contain various corrosive impurities, such as hypersalinity water, dissolved oxygen, carbon dioxide, oxygen sulfide, sulfate reducing bacteria, chloride ions and the like, can aggravate the corrosion of the inner wall of the metal pipeline under the composite action of temperature, pressure, flow rate, alternating stress and other factors. In addition, the pipelines in the oilfield station are complex, the valves, elbows, tees, reducing pumps and ground facilities are numerous, the surface states of materials and metals are different, localized corrosion such as galvanic corrosion is easy to occur, corrosion products are accumulated, and therefore corrosion is increased. At present, three modes of adding anti-corrosion and anti-scale agents into bare pipes and replacing the bare pipes with nonmetallic pipelines, pipeline inner coatings or inner liners are mainly adopted for the anti-corrosion treatment of the pipe network in the station. However, these approaches have limitations. The bare pipe is added with the medicament, the corrosion environment is not changed, the equipment investment is not increased, but the medicament dosage is difficult to control, and the anti-corrosion effect is unstable. The non-metal pipeline is replaced, so that the non-metal pipeline is inferior to a metal pipeline in high temperature resistance, pressure resistance and wear resistance, and has high operation and maintenance cost and limited application range. The lining technology and the coating rule have the problems of high construction difficulty, high cost, incapability of repairing after aging, easy falling of the coating and the like, so that the anti-corrosion effect is unstable. In view of the technical problems of unstable corrosion prevention effect and high corrosion prevention treatment cost of the inner wall corrosion prevention treatment mode of the oilfield station pipeline in the prior art, it is necessary to design an innovative anticorrosion protection device for the inner wall of the oilfield station metal pipeline so as to improve the corrosion prevention effect, prolong the service life of the oilfield station pipeline, reduce the corrosion prevention treatment cost and finally ensure the stable and reliable operation of the oilfield station. Disclosure of Invention The invention aims to solve the problems in the prior art, and provides an anti-corrosion protection device and method for the inner wall of a metal pipeline of an oilfield station, which effectively solve the technical problems of unstable anti-corrosion effect and high anti-corrosion treatment cost of the inner wall of the metal pipeline of the oilfield station, realize stable and effective anti-corrosion protection of the inner wall of the metal pipeline of the oilfield station, and prolong the service life of the protected metal pipeline. In order to achieve the above purpose, the technical scheme adopted by the invention is as follows: On one hand, the invention provides an anti-corrosion protection device for the inner wall of a metal pipeline of an oilfield station, which comprises a metal pipe body communicated with a protected metal pipeline of the oilfield station, wherein a metal net cage is arranged in the metal pipe body, a sacrificial anode layer is cast on the inner surface of the metal pipe body, the metal net cage is wrapped in the sacrificial anode layer, the metal pipe body is respectively and electrically connected with the metal net cage and the sacrificial anode layer, and the device is electrically connected with the protected metal pipeline and protects the protected metal pipeline through a sacrificial anode cathode protection principle. Preferably, the outer surface of the metal net cage is provided with a plurality of conductive contact strips, the end parts of the conductive contact strips are clung to the inner surface of the metal pipe body, and the metal net cage and the conductive contact strips are wrapped in the sacrificial anode layer. Preferably, the sacrificial anode layer is made of any one of aluminum alloy and zinc alloy, the thickness of the sacrificial anode layer wrapped on the metal net cage is D1, and D1 is more than or eq