Anti-corrosion technology and application of oil pipe pup joints

The produced fluid in oilfield development and production has high salinity and contains sulfide, carbon dioxide, oxygen, sulfate anaerobic bacteria, etc., which are strong electrolytes and are highly corrosive to down hole tubing and casing.Pup joints are a common component in industrial pipeline connections. Short joints are divided into oil pipe pup joints and line pipe pup joints. The oil pipe nipple is a short section of oil pipe. Compared with the oil pipe, only the length is different, and everything else is the same.Oil pipe anti-corrosion pup joint technology is a commonly used pipeline anti-corrosion method, which can effectively prevent pipelines from being damaged due to corrosion during transportation and use.Let’s take a detailed look at the anti-corrosion pup joint technology of oil pipes and its application in engineering.

The principle of oil pipe anti-corrosion pup joint technology is to use special anti-corrosion treatment at the joints of pipelines to form an area with good anti-corrosion performance, thereby effectively preventing corrosion media from eroding the pipeline. This technology usually includes surface treatment, coating protection, cathodic protection and other methods to improve the anti-corrosion ability of pipelines.

Working principle of oil pipe anti-corrosion pup joint：

Different metals have different potentials in electrolyte solutions. When two metals are in the same electrolyte, due to the different potential differences between the two metals, electrons will continue to move to form a current. The greater the potential difference between the two metals, the greater the voltage generated. big. At this time, the surface of the anode end continues to lose electrons, an oxidation reaction occurs, and the metal atoms are converted into positive ions, forming hydroxides, which are corroded; while the surface of the cathode end continues to gain electrons, a reduction reaction occurs, and no corrosion occurs.

Corrosion principle:

The principle of cathodic protection technology is to use materials with active metals to replenish a large number of electrons to the oil pipes in the well, so that the entire protected metal is in a state of excess electrons, thereby achieving the purpose of anti-corrosion of metal materials. The sacrificial anode anti-corrosion oil pipe pup uses a metal that is more active than the oil pipe in the well to act as an anode. It loses electrons in the electrolyte solution in the wellbore and is consumed by corrosion. The inner oil pipe acts as a cathode to gain electrons and is not easily corroded and is protected.

Systems in petroleum, natural gas, chemical industry and other fields. Its main advantages include:

Improve the service life of pipelines: Through effective anti-corrosion pup joint technology, the service life of pipelines can be greatly extended and maintenance and replacement costs can be reduced.

Reduce environmental pollution: Preventing pipeline corrosion and leakage can effectively reduce pollution to the surrounding environment and protect the ecological environment.

Improve safety: Anti-corrosion short-circuit technology can reduce the risk of safety accidents such as pipeline leaks and explosions, and ensure the safety of facilities and personnel.

Reduced operating costs: As the pipeline maintenance cycle is extended and the failure rate is reduced, the cost of pipeline operations can be effectively reduced.

The specific applications of anti-corrosion pup joint technology for casing and tubing include the following aspects:

Surface treatment: Surface treatment is carried out at the oil pipe connection, such as spraying anti-corrosion paint, hot-dip galvanizing, etc., to form a protective film to block the erosion of the pipeline by corrosive media.

Coating protection: Use special anti-corrosion coatings, such as epoxy resin coatings, polyethylene coatings, etc., to improve the corrosion resistance of pipelines.

Cathodic Protection: Reduce corrosion by installing cathodic protection equipment, such as cathodic protection galvanic systems, on the surface of the pipeline, making the pipeline a cathode.

Insulation layer: An insulation layer is installed at the pipe connection to prevent direct contact of corrosive media with the pipeline and improve the corrosion resistance of the pipeline.

The technical parameters of oil pipe anti-corrosion Pup Joint are as follows. Anode dimensions: φ102mmx460mm; Anode alloy materials: A1, Zn; Design life: 3 years; Installation position: One oil pipe is installed every 90~100m.

In general, oil pipe anti-corrosion plug joint technology has important application value in the engineering field. It can ensure the safe and stable operation of the pipeline system, reduce environmental pollution, and reduce operating costs. It is a very effective pipeline anti-corrosion method. With the continuous advancement of science and technology, I believe this technology will be more widely used and developed.