CN112439678B - Anticorrosion coating process in oil casing - Google Patents
Anticorrosion coating process in oil casing Download PDFInfo
- Publication number
- CN112439678B CN112439678B CN201910839439.6A CN201910839439A CN112439678B CN 112439678 B CN112439678 B CN 112439678B CN 201910839439 A CN201910839439 A CN 201910839439A CN 112439678 B CN112439678 B CN 112439678B
- Authority
- CN
- China
- Prior art keywords
- coating
- oil casing
- wall
- oil
- pipe
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000000576 coating method Methods 0.000 title claims abstract description 278
- 239000011248 coating agent Substances 0.000 claims abstract description 204
- 238000005260 corrosion Methods 0.000 claims abstract description 59
- 238000000034 method Methods 0.000 claims abstract description 52
- 238000003754 machining Methods 0.000 claims abstract description 34
- 238000004140 cleaning Methods 0.000 claims abstract description 25
- 238000003860 storage Methods 0.000 claims abstract description 24
- 230000008878 coupling Effects 0.000 claims abstract description 22
- 238000010168 coupling process Methods 0.000 claims abstract description 22
- 238000005859 coupling reaction Methods 0.000 claims abstract description 22
- 238000012545 processing Methods 0.000 claims abstract description 20
- 239000002173 cutting fluid Substances 0.000 claims abstract description 14
- 238000007689 inspection Methods 0.000 claims description 56
- 239000010410 layer Substances 0.000 claims description 55
- 238000007789 sealing Methods 0.000 claims description 54
- 230000001681 protective effect Effects 0.000 claims description 44
- 238000005520 cutting process Methods 0.000 claims description 38
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 claims description 37
- 230000007797 corrosion Effects 0.000 claims description 24
- 238000005507 spraying Methods 0.000 claims description 19
- 238000005488 sandblasting Methods 0.000 claims description 12
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 12
- 239000000463 material Substances 0.000 claims description 10
- 238000005422 blasting Methods 0.000 claims description 9
- 238000004806 packaging method and process Methods 0.000 claims description 9
- 239000000428 dust Substances 0.000 claims description 7
- 239000004033 plastic Substances 0.000 claims description 6
- 238000010926 purge Methods 0.000 claims description 6
- 238000005303 weighing Methods 0.000 claims description 6
- 239000011253 protective coating Substances 0.000 claims description 4
- 238000010422 painting Methods 0.000 claims description 3
- 239000011241 protective layer Substances 0.000 claims description 2
- 230000003628 erosive effect Effects 0.000 claims 1
- 230000009477 glass transition Effects 0.000 claims 1
- 239000003973 paint Substances 0.000 abstract description 10
- 230000002950 deficient Effects 0.000 abstract description 3
- 238000004519 manufacturing process Methods 0.000 description 23
- 238000005536 corrosion prevention Methods 0.000 description 17
- 239000004519 grease Substances 0.000 description 12
- 238000007664 blowing Methods 0.000 description 7
- 239000004576 sand Substances 0.000 description 6
- 238000009434 installation Methods 0.000 description 5
- 238000007665 sagging Methods 0.000 description 5
- 238000005452 bending Methods 0.000 description 4
- 238000001035 drying Methods 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- 239000002344 surface layer Substances 0.000 description 4
- 229910000831 Steel Inorganic materials 0.000 description 3
- 230000007547 defect Effects 0.000 description 3
- 239000007788 liquid Substances 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- 229910052751 metal Inorganic materials 0.000 description 3
- 239000010959 steel Substances 0.000 description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 238000001514 detection method Methods 0.000 description 2
- 238000010892 electric spark Methods 0.000 description 2
- 230000007613 environmental effect Effects 0.000 description 2
- 230000002349 favourable effect Effects 0.000 description 2
- 239000011521 glass Substances 0.000 description 2
- 238000000227 grinding Methods 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 239000012535 impurity Substances 0.000 description 2
- 238000002955 isolation Methods 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 238000011160 research Methods 0.000 description 2
- 239000002689 soil Substances 0.000 description 2
- 238000007711 solidification Methods 0.000 description 2
- 230000008023 solidification Effects 0.000 description 2
- 230000003746 surface roughness Effects 0.000 description 2
- 229910000851 Alloy steel Inorganic materials 0.000 description 1
- 229910000975 Carbon steel Inorganic materials 0.000 description 1
- 239000004593 Epoxy Substances 0.000 description 1
- 102220498074 Transmembrane 4 L6 family member 20_N80Q_mutation Human genes 0.000 description 1
- 239000008186 active pharmaceutical agent Substances 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000010962 carbon steel Substances 0.000 description 1
- 230000003749 cleanliness Effects 0.000 description 1
- 230000001427 coherent effect Effects 0.000 description 1
- 238000007334 copolymerization reaction Methods 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000007590 electrostatic spraying Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 229920006334 epoxy coating Polymers 0.000 description 1
- 230000002209 hydrophobic effect Effects 0.000 description 1
- 239000003112 inhibitor Substances 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 239000003129 oil well Substances 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
- 238000013021 overheating Methods 0.000 description 1
- -1 polytetrafluoroethylene Polymers 0.000 description 1
- 229920001343 polytetrafluoroethylene Polymers 0.000 description 1
- 239000004810 polytetrafluoroethylene Substances 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 230000000750 progressive effect Effects 0.000 description 1
- 230000001012 protector Effects 0.000 description 1
- 238000012797 qualification Methods 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 238000006748 scratching Methods 0.000 description 1
- 230000002393 scratching effect Effects 0.000 description 1
- 239000002356 single layer Substances 0.000 description 1
- 239000007921 spray Substances 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D7/00—Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials
- B05D7/22—Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials to internal surfaces, e.g. of tubes
- B05D7/222—Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials to internal surfaces, e.g. of tubes of pipes
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D3/00—Pretreatment of surfaces to which liquids or other fluent materials are to be applied; After-treatment of applied coatings, e.g. intermediate treating of an applied coating preparatory to subsequent applications of liquids or other fluent materials
- B05D3/002—Pretreatement
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D3/00—Pretreatment of surfaces to which liquids or other fluent materials are to be applied; After-treatment of applied coatings, e.g. intermediate treating of an applied coating preparatory to subsequent applications of liquids or other fluent materials
- B05D3/02—Pretreatment of surfaces to which liquids or other fluent materials are to be applied; After-treatment of applied coatings, e.g. intermediate treating of an applied coating preparatory to subsequent applications of liquids or other fluent materials by baking
- B05D3/0218—Pretreatment, e.g. heating the substrate
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D3/00—Pretreatment of surfaces to which liquids or other fluent materials are to be applied; After-treatment of applied coatings, e.g. intermediate treating of an applied coating preparatory to subsequent applications of liquids or other fluent materials
- B05D3/12—Pretreatment of surfaces to which liquids or other fluent materials are to be applied; After-treatment of applied coatings, e.g. intermediate treating of an applied coating preparatory to subsequent applications of liquids or other fluent materials by mechanical means
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
- B05D5/00—Processes for applying liquids or other fluent materials to surfaces to obtain special surface effects, finishes or structures
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B08—CLEANING
- B08B—CLEANING IN GENERAL; PREVENTION OF FOULING IN GENERAL
- B08B9/00—Cleaning hollow articles by methods or apparatus specially adapted thereto
- B08B9/02—Cleaning pipes or tubes or systems of pipes or tubes
- B08B9/027—Cleaning the internal surfaces; Removal of blockages
- B08B9/032—Cleaning the internal surfaces; Removal of blockages by the mechanical action of a moving fluid, e.g. by flushing
- B08B9/0321—Cleaning the internal surfaces; Removal of blockages by the mechanical action of a moving fluid, e.g. by flushing using pressurised, pulsating or purging fluid
- B08B9/0328—Cleaning the internal surfaces; Removal of blockages by the mechanical action of a moving fluid, e.g. by flushing using pressurised, pulsating or purging fluid by purging the pipe with a gas or a mixture of gas and liquid
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23G—THREAD CUTTING; WORKING OF SCREWS, BOLT HEADS, OR NUTS, IN CONJUNCTION THEREWITH
- B23G1/00—Thread cutting; Automatic machines specially designed therefor
- B23G1/22—Machines specially designed for operating on pipes or tubes
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Life Sciences & Earth Sciences (AREA)
- Wood Science & Technology (AREA)
- Application Of Or Painting With Fluid Materials (AREA)
Abstract
The invention provides an anticorrosive coating process for an oil casing. The process comprises the following steps: 1) Cleaning the inner wall of the flat-end oil casing; 2) Coating and curing an anticorrosive coating on the inner wall of the flat-end oil casing pipe body; 3) Processing the threads of the end of the oil casing pipe; in the process of thread machining, the highest temperature of the inner wall of the thread machining part does not exceed 90% of the upper temperature resistance limit value of the anticorrosive coating of the pipe body in centigrade degrees; the cutting fluid used for thread processing does not damage the anticorrosive coating coated on the inner wall of the oil sleeve; 4) And the oil casing pipe is used for coupling tightening and pipe end protection, so that the whole anti-corrosion coating process in the oil casing pipe is completed. The process flow is simple, the defective product generation probability is low, the coating method is well suitable for coating the high-temperature-resistant anticorrosive paint in the oil casing, and the coating method is low in price and can be used for coating the low-end and conventional paint in the oil casing for temporary storage, transportation and the like.
Description
Technical Field
The invention belongs to the field of corrosion prevention in oil casings, and relates to a corrosion prevention coating process in an oil casing.
Background
Oil casings and other downhole string components (e.g., drill pipe) are predominantly carbon steel and low alloy steel, and corrosion is one of the major causes of reduced or failed function. Corrosion of oil casing and other products mainly occurs in two links: the first is atmospheric environmental corrosion during transportation and storage, especially in high temperature, high humidity, high salt environments; the second type is a corrosive medium (e.g., H) in the environment of use2S、CO2And SRB, etc.). The corrosion damage of the oil casing causes the delay and pause of the production operation for the light, and the abandonment of the oil-gas well for the heavy and serious environmental damage accidents. Because the inner wall of the oil casing often needs to be contacted with various corrosive mediums for a long time, the corrosion of the inner wall is more common and serious, and the inner corrosion resistance is more urgent and important.
At present, the corrosion prevention of the coating in the oil casing is an economic and effective internal corrosion prevention mode commonly adopted in the industry. A mature internal anti-corrosion coating process is formed, and even has industrial specifications, such as SY/T6717 technical conditions for internal coatings of oil pipes and sleeves. The traditional method adopts the following process routes: the method comprises the steps of finished oil casing inspection in factory → removal of thread protection caps at two ends → cleaning of thread protection caps at field ends → installation of temporary thread protection caps at two ends → inner wall sand blasting and rust removal → inner wall purging and cleaning → inner wall coating of an anticorrosive layer → drying and curing (if needed) → quality inspection of the anticorrosive layer → removal of the temporary thread protection caps → cleaning and inspection of the thread at field ends → re-application of the thread protection caps at field ends → re-installation of the thread protection caps at two ends. The process route meets the coating requirement of the coating in the oil sleeve, but the complex processes of repeated assembly and disassembly of the thread protective cap, repeated cleaning and coating of thread grease and the like not only cause complex process and high cost, but also have low efficiency and high error rate (mainly manual implementation). More importantly, although temporary thread protective caps are installed at two ends of the oil casing in the sand blasting and coating stages, the strong penetrability of fine sand grains often causes the sand grains to be embedded into thread gaps, which poses great challenges for subsequent manual cleaning and thread inspection, and once the sand grains are not cleaned in time, the connection and sealing of the subsequent oil casing are greatly threatened, and the consequence is serious! Due to the fact that the actual application of the oil casing inner coating anticorrosion technology is greatly limited, especially the oil casing inner coating of the high-temperature resistant coating and the oil casing inner coating of the low-end anticorrosion material used in the storage and transportation process.
Therefore, how to achieve the purposes of effectively improving the coating efficiency, reducing the coating cost, reducing and even avoiding the secondary quality risk and improving the coating quality through reasonably optimizing and simplifying the coating process becomes the key of the current key oil casing internal corrosion prevention research.
Disclosure of Invention
Aiming at the defects of the prior art, the invention aims to provide an oil casing internal corrosion-resistant coating process which is simple in process and low in generation probability of oil casing defective products. The process can be well suitable for coating the high-temperature-resistant anticorrosive paint in the oil casing, and can realize coating the low-end paint in the oil casing for temporary storage, transportation and the like at low cost.
In order to achieve the above object, the present invention provides an oil casing internal corrosion prevention coating process, which comprises the following steps:
1) Cleaning the inner wall of a flat-end oil sleeve (namely the oil sleeve which is not subjected to thread machining); the oil casing comprises at least one of an oil pipe and a casing;
2) After the inner wall of the oil casing is swept and cleaned, coating and curing an anticorrosive coating on the inner wall of the pipe body;
3) Coating an anticorrosive coating on the inner wall of the pipe body and curing the anticorrosive coating, and then machining the end threads of the oil casing pipe; in the process of thread machining, the highest temperature of the inner wall of the thread machining part is not more than 90% of the upper temperature resistance limit value of the anticorrosive coating of the pipe body in centigrade degree; the cutting fluid used for thread processing does not damage the anticorrosive coating coated on the inner wall of the oil sleeve;
4) And after the oil casing pipe end threads are processed, the coupling is screwed down and the pipe end is protected, so that the whole anti-corrosion coating process in the oil casing pipe is completed.
In the above oil casing internal corrosion prevention coating process, preferably, before the inner wall of the flat-end oil casing is cleaned, appearance inspection is performed, where the appearance inspection includes inspecting whether the oil casing body is damaged, whether dirt exists on the inner wall of the oil casing, and whether foreign matter exists on the inner wall of the oil casing; if the oil casing body is damaged, the oil casing does not carry out the subsequent steps; if dirt exists on the inner wall of the oil casing, cleaning the dirt; if foreign matters exist in the oil casing, the foreign matters are removed; the damage may include at least one of a collision damage, a pit damage, a scratch damage, a bending damage, but is not limited thereto; the soil may include oil, but is not limited thereto; the foreign matter may include an embedded scale, but is not limited thereto.
In the above oil casing internal corrosion prevention coating process, preferably, the inner wall cleaning treatment includes inner wall rust removal treatment and inner wall purging cleaning.
In the above oil casing internal corrosion prevention coating process, when performing an inner wall rust removal treatment, preferably, when the anticorrosive coating to be coated is an anticorrosive coating for temporary storage, the inner wall rust removal treatment is performed by at least one of manual and power tool rust removal, for example, power tools such as a steel brush can be used for rust removal according to the coating requirement and the coating performance; more preferably, the inner wall rust removing treatment has a rust removing grade of not less than St 2.0 in GB/T8923.1 and/or ISO 8501-1.
In the above-described anticorrosive coating process for an oil jacket pipe, when performing rust removal treatment of the inner wall, preferably, when the anticorrosive coating to be coated is another anticorrosive coating other than the anticorrosive coating for temporary storage, the rust removal treatment is performed by at least one of sand blasting rust removal and shot blasting rust removal; more preferably, the derusting grade of the inner wall derusting treatment is not lower than Sa 2.5 in GB/T8923.1 and/or ISO 8501-1. The abrasive for rust removal (such as all sand for sand blasting and rust removal and shot for shot blasting treatment) should be kept clean and free of impurities. When the sand blasting rust removal and/or the shot blasting rust removal are/is carried out, the grinding materials are added and replaced according to proper frequency, and when the grinding materials comprise sand and shots, a proper sand-shot ratio is maintained.
In the oil casing internal corrosion prevention coating process, when the internal wall is cleaned by blowing, preferably, when the corrosion prevention layer to be coated is a temporary storage corrosion prevention layer, the dust degree of the internal wall after cleaning by blowing meets the requirement of GB/T18570.3 and/or ISO8502-3 of grade 2 or above, namely meets the requirement of GB/T18570.3 and/or ISO8502-3 of grade 2 or higher.
In the oil casing internal anticorrosive coating process, when the inner wall is cleaned by blowing, preferably, when the anticorrosive coating to be coated is other anticorrosive coatings except for the anticorrosive coating for temporary storage, the dust degree of the inner wall after cleaning by blowing should meet the requirement of grade 1 or more of GB/T18570.3 and/or ISO8502-3, namely, the requirement of grade 1 or higher of GB/T18570.3 and/or ISO 8502-3.
In the anti-corrosion coating process in the oil casing, when the inner wall is purged and cleaned, the inner wall may be purged and cleaned by using compressed air, but the process is not limited thereto.
In the oil casing internal corrosion prevention coating process, the oil casing is preferably subjected to a pipe body inner wall corrosion prevention layer coating treatment before rust return, and the time interval from the rust removal treatment to the coating is generally required to be not more than 4 hours (which can be adjusted according to the temperature and humidity).
In the oil casing pipe inner anti-corrosion coating process, when the coating treatment of the anti-corrosion layer on the inner wall of the pipe body is carried out, the spraying parameters are set according to the technical requirements of the anti-corrosion layer coating and the paint characteristics of the anti-corrosion layer under the condition of meeting the spraying environment requirement, and the anti-corrosion coating operation in the pipe body is carried out. The coating process preferably monitors parameters periodically, and is more favorable for ensuring that the spraying parameters are qualified. When the anticorrosive coating coated on the inner wall of the oil casing pipe body is not a high-temperature-resistant anticorrosive coating, the coating temperature is preferably not higher than 200 ℃; when the anticorrosive coating coated on the inner wall of the oil casing pipe body is a high-temperature-resistant anticorrosive coating, the oil casing pipe body can be preheated and then coated with the anticorrosive coating, wherein the preheating temperature is preferably not lower than 260 ℃, and the coating temperature is preferably 220-250 ℃ or not lower than the conversion temperature of coating glass plus 20 ℃ (namely the coating temperature is preferably 220-250 ℃ or not lower than the first temperature, and the conversion temperature of the coating glass plus 20 ℃ is the first temperature).
In the oil casing pipe inner anti-corrosion coating process, the anti-corrosion layer can be coated for multiple times and multiple layers according to requirements, the coating and coating parameters of each layer are specifically determined according to requirements, and the coating can be cured as required after each time or layer of coating. According to the requirements of the anticorrosive coating and the performance characteristics of the anticorrosive coating, after each time and/or each layer and/or all layers are coated, the whole pipe body can be arranged to enter a curing furnace for high-temperature curing or be stood in the air for normal-temperature curing.
In the oil casing internal anti-corrosion coating process, preferably, after the oil casing is subjected to coating treatment and curing treatment of the anti-corrosion layer on the inner wall of the oil casing, before the thread processing of the end of the oil casing, the quality inspection of the anti-corrosion layer is performed, when the quality inspection of the anti-corrosion layer of the oil casing is qualified, the oil casing is subjected to subsequent thread processing of the end of the oil casing, and when the quality inspection of the anti-corrosion layer is unqualified, the oil casing is subjected to coating treatment of the anti-corrosion layer on the inner wall of the oil casing and curing treatment of the anti-corrosion layer again; the quality inspection of the anticorrosive coating may include, but is not limited to, inspecting whether defects such as missing coating, vacuum, sagging, etc. exist and inspecting whether the thickness of the anticorrosive coating is acceptable. Performing a quality inspection of the anticorrosive layer, which can be performed by an inspection method known to those skilled in the art; the standard for judging whether the quality inspection of the anticorrosive coating is qualified can be a standard for judging whether the anticorrosive coating is qualified or not, which is known by a person skilled in the art. In the process of inspecting the quality of the anticorrosive coating, the pipe end of the oil casing is a flat end without threads and a coupling, so that the inspection convenience and reliability are greatly improved.
In the above oil casing internal anticorrosion coating process, preferably, during the pipe end thread machining, a protective plug (i.e. a protective plug) is added inside the pipe end of the oil casing, and the protective plug is used for preventing chips in the thread machining process from entering the inside of the oil casing pipe body to damage the protective layer. In the traditional process, the problems of scratching inside the pipe body caused by chips in the process of machining the thread at the end of the pipe and deposition of the chips inside the pipe body are never formally solved by technical personnel in the field.
In the oil casing internal corrosion-resistant coating process, preferably, the protective plug is made of a flexible material; more preferably, the flexible material is rubber plastic; for example, polytetrafluoroethylene may be used to make the protective plug.
In the above oil casing internal corrosion-resistant coating process, preferably, the protective plug includes a sealing portion located at the rear end and a friction portion located at the front end, the sealing portion is used for being attached to the inner wall of the oil casing in a sealing manner, and the friction portion is used for being clamped with the inner wall of the oil casing.
In a preferred embodiment, the sealing part is also provided with a handle, and the handle is arranged at the rear end of the sealing part; more preferably, the sealing part is provided with a groove at the handle arrangement part so as to facilitate the hand holding of the handle and/or the detachment of the protective plug by using a tool. In the using process of the protective plug, in order to avoid interference on external thread machining and other procedures, the protective plug can be properly inserted into the end face of the oil casing pipe by 0.5cm-1cm, and a handle can be arranged for taking out the protective plug from the oil casing pipe conveniently; the location of the handle may be located at a convenient location to find and contact from outside the oil jacket. For example, the handle is arranged at the tail part of the sealing part and is arranged at the center of the end surface of the sealing part. On the other hand, the sealing part and the inner wall of the oil sleeve are in interference fit, and the opening of the handle can further facilitate the use of putting in and taking out the handle for copolymerization, so that the use of the protective plug is facilitated, for example, a proper groove is arranged at the position where the handle is arranged.
In a preferred embodiment, the sealing portion is cylindrical, and the outer wall of the sealing portion is used for being attached to the inner wall of the oil casing.
In a preferred embodiment, the friction part is provided with an inverted tooth structure; more preferably, the inverted tooth-shaped structure has m inverted teeth, and tooth tops of the inverted teeth are used for contacting with the inner wall of the oil sleeve; m is a positive integer greater than 1; wherein the addendum circle diameter of the inverted tooth structure is preferably equal to the diameter of the sealing portion. The inverted tooth structure is a sawtooth structure with the direction opposite to the extending direction of the oil casing. The number of the inverted teeth can be determined according to the friction intensity required for working, for example, the inverted tooth structure has 4 inverted teeth. The tooth tops of the inverted teeth contact the inner wall of the oil sleeve, and friction between the protective plug and the inner wall of the oil sleeve is increased through air pressure in tooth gaps of the inverted teeth and friction force generated by linear contact of the inverted teeth and the inner wall of the oil sleeve.
In a preferred embodiment, a thread-shaped structure is arranged on the friction part; more preferably, the surface spiral line of the thread-shaped structure is used for contacting with the inner wall of the oil sleeve; further preferably, an outer diameter of the thread-shaped structure is equal to a diameter of the sealing portion. The pitch of the thread structure may be determined according to the frictional strength required for operation. The surface spiral line of the thread contacts the inner wall of the oil sleeve, and the friction between the protective plug and the inner wall of the oil sleeve is increased through the air pressure between the threads and the friction force generated by the contact of the threads and the inner wall line of the oil sleeve.
Due to the design of the inverted tooth-shaped structure or the threaded structure, excessive friction between the sealing part and the inner wall of the oil sleeve due to different roundness is reduced, and meanwhile, the friction strength of the protective plug is ensured.
In a preferred embodiment, the sealing portion is integrally formed with the friction portion. Because of the real condition in the oil sleeve, the sealing part and the friction part are stressed differently and are both larger when the oil sleeve is pulled out and plugged in, if a method of connecting after manufacturing respectively is adopted, the damage of the protective plug is easy to cause, and the manufacture is inconvenient, so the sealing part and the friction part are preferably arranged into an integral molding.
In practical application, the actual shape of the cross section of the oil casing is not a complete circle, and the oil casing has a certain roundness tolerance, so that the oil casing is difficult to match due to different roundness when the sealing part is placed in the oil casing, and overlarge friction force is generated; therefore, the sealing part with a complete circle cross section can be designed to be shorter so as to reduce the excessive friction force brought by different roundness; and the front end of the protective plug is provided with a friction part with stronger deformation degree and larger friction force, thereby ensuring the isolation quality of the protective plug.
The protective plug is used in the oil sleeve internal anti-corrosion coating process, through interference fit of the sealing portion and the inner wall of the oil sleeve and static friction force generated by the friction portion and the inner wall of the oil sleeve, good isolation effect is achieved on the internal space of the oil sleeve and the external environment in the process of thread machining of the oil sleeve, and chips generated in the process of thread machining of the oil sleeve are prevented from entering the oil sleeve to scratch the coated anti-corrosion coating and influence the anti-corrosion effect of the anti-corrosion coating.
In the anti-corrosion coating process in the oil sleeve, in the process of thread machining, the highest temperature of the inner wall of a thread machining part does not exceed 90% of the upper temperature resistance limit value of the anti-corrosion layer of the pipe body in centigrade, and the anti-corrosion coating process can be realized by optimizing the temperature control scheme of pipe thread forming cutter cutting, such as cutting speed and cutting amount control, optimizing cutting fluid formula and the like; the highest temperature of the inner wall of the threaded part does not exceed 90% of the upper temperature resistance limit value of the anticorrosive coating of the pipe body by adopting a cutting temperature control mode in the conventional cutting process. Through tests, cutting control parameter series (cutting speed and maximum cutting amount) with different maximum temperatures of oil casings of different specifications can be established, and water-based cutting fluid is adopted, so that the coating is prevented from being damaged, and heat can be quickly taken away. The highest temperature of the inner wall of the threaded part does not exceed 90% of the upper temperature resistance limit value of the anticorrosive coating of the pipe body, so that the anticorrosive coating can be better protected, and the high quality and low defective rate of a final finished product can be better guaranteed.
In the anti-corrosion coating process for the oil casing pipe, the cutting speed, the single cutting amount and the cutting fluid formula during the thread machining process of the oil casing pipe with each size are preferably controlled as shown in the following table 1:
TABLE 1
| Oil casing size (mm) | Cutting speed (rpm) | Maximum cutting amount per time (mm) | Cutting fluid |
| ≥60.32,<168.28 | 55-155 | First cutting: 0.3, last knife: 0.1 | Fully synthetic water-based type |
| ≥168.28,<298.45 | 30-60 | First cutting: 0.4, last knife: 0.2 | Fully synthetic water-based type |
| ≥298.45,<406.40 | 20-35 | Firstly, cutting: 0.5, last knife: 0.2 | Fully synthetic water-based type |
| ≥406.4,<508.00 | 16-25 | Firstly, cutting: 0.5, last knife: 0.2 | Fully synthetic water-based type |
Wherein, the oil casing size refers to the oil casing external diameter.
In the oil casing pipe internal anticorrosion coating process, in the pipe end thread machining process, besides temperature control, chip cleaning and protection work is required, so that mechanical damage of a coated anticorrosion layer caused by chips is avoided; when the anticorrosive coating does not have certain mechanical damage self-repairing function, preferably install the protection stopper additional in the pipe end of oil casing, the protection stopper is used for keeping away the smear metal entering oil casing body internal damage inoxidizing coating in the screw thread course of working, wherein the protection stopper preferably is the convenient and fast protection stopper of installation dismantlement.
In the above-described oil casing internal corrosion prevention coating process, it is preferable that the oil casing is coated with thread grease at the oil casing thread before the collar tightening and the pipe end protection are performed.
In the above oil casing internal corrosion prevention coating process, preferably, the oil casing is subjected to thread inspection after the oil casing is subjected to oil casing pipe end thread machining and before coupling tightening and pipe end protection; and when the thread is detected to be qualified, performing subsequent steps on the oil casing, and when the thread is detected to be unqualified, removing the unqualified thread section by adopting a mechanical cold cutting mode and then re-processing the thread at the end of the oil casing. The thread inspection may include, but is not limited to, inspecting the size and appearance of the threads. The thread inspection can be performed by a conventional thread inspection method, and the qualification of the thread inspection can be performed by a standard of a conventional thread inspection, but is not limited thereto.
In the above process of coating the inner surface of the oil casing with the corrosion inhibitor, the oil casing may be subjected to coupling tightening and pipe end protection in the following manner: and (3) screwing the oil casing into a coupling, installing a coupling gap protection ring according to the requirement, and then smearing thread grease and/or storage grease and installing a thread protection cap.
In the above anti-corrosion coating process in the oil casing, preferably, after the oil casing is subjected to collar tightening and pipe end protection, the whole body of the oil casing and the end of the collar are subjected to drift diameter inspection, and the drift diameter inspection is in accordance with the requirement of API spec.5ct; the drift diameter rod used for the drift diameter inspection is preferably a plastic drift diameter rod; and the metal drift diameter rod is more favorable for avoiding damaging the coated anticorrosive coating.
In the anti-corrosion coating process for the oil casing, preferably, the process further comprises the step 5) of weighing, measuring length, packaging and warehousing the oil casing after the coupling is screwed down and the pipe end is protected; wherein the packaging comprises painting on the outer surface of the oil casing pipe body and spraying the mark of the pipe body.
The invention starts from the flow of the oil casing internal anticorrosion coating process, breaks the established mode of firstly processing the screw thread and then coating the anticorrosion layer, and provides a novel oil casing internal anticorrosion coating process flow. Compared with the traditional process, the technical scheme provided by the invention has the following beneficial effects:
(1) The technical scheme provided by the invention omits a plurality of processes of cleaning and re-smearing the thread grease, repeatedly assembling and disassembling the thread protection cap and the like which are realized by manpower, effectively reduces the manual configuration of production lines (5-8 workers/shift are saved in each production line), improves the coating production efficiency (about 30% of the production efficiency is improved compared with the traditional method), reduces the total production cost (about 5-10 yuan per square meter is saved), completely avoids the thread connection risk caused by the damage of the thread of the pipe end, sand inclusion and the like easily caused by the traditional process, and avoids the adverse effect of thread protection measures on the coating quality of the pipe end.
(2) The technical scheme provided by the invention has wider applicability, and particularly realizes the coating of a high-temperature resistant anticorrosive coating and the coating of a low-end anticorrosive coating for temporary storage and the like;
for better solving the corrosion prevention under high-temperature well (such as high temperature higher than 150 ℃), the coating of a high-temperature resistant anticorrosive layer is generally required to be carried out inside the oil casing; the coating of the high-temperature-resistant anticorrosive coating usually needs higher pipe body preheating and coating temperatures, and the overhigh preheating and coating temperatures can generate larger negative effects on the thread precision, the connection and the sealing performance of the oil casing pipe;
the traditional process is generally applied to coating of an anticorrosive coating (i.e. a relatively high-end anticorrosive coating for avoiding corrosion in a downhole working condition environment) adapted to well and mine conditions; however, oil casings as bulk materials for oil fields often require long-term storage on the oil field site, and therefore conventional corrosion protection under storage and transportation conditions is extremely essential in addition to corrosion protection under well conditions. At present, the oil casing pipe can only ensure that large-area corrosion can not occur within three months under the storage and transportation conditions. For the ground temporary storage for more than three months, no proper treatment mode exists, although the corrosion problem of the oil casing in the storage and transportation process can be solved by coating the low-end anticorrosive coating, the coating of the anticorrosive coating for the low-end temporary storage by adopting the traditional process has no practicability due to the complex flow, high cost and the like; the process provided by the scheme greatly reduces the coating economy, is suitable for coating the anticorrosive coating for low-end temporary storage, and greatly widens the application of the low-end anticorrosive coating for temporary storage and the like.
(3) The technical scheme provided by the invention avoids the inconvenience brought to the operations of removing rust, blowing, coating the anticorrosive coating and the like and the influence on the quality of the coated anticorrosive coating caused by the existence of special objects such as threads, couplings and the like in the coating process of the anticorrosive coating in the traditional process.
Drawings
Fig. 1 is a flow chart of the anticorrosion coating process in the oil casing.
Fig. 2 is a sectional view of the shield plug a.
Fig. 3 is a right side view of the protective plug a.
Fig. 4 is a sectional view of the protective plug B.
Fig. 5 is a sectional view of the protective plug C.
Detailed Description
The technical solutions of the present invention will be described in detail below in order to clearly understand the technical features, objects, and advantages of the present invention, but the present invention is not limited to the practical scope of the present invention.
In one embodiment, the process for coating the oil casing with an anticorrosive coating is shown in fig. 1, and comprises the following steps:
Example 1
The embodiment provides a corrosion-resistant coating process in a sleeve
The raw materials used in the process are 244.48mm in outer diameter, 11.99mm in wall thickness and N80Q steel-grade plain-end sleeves.
The anticorrosion coating process in the sleeve comprises the following steps:
(1) After entering a coating factory for carrying out pipe body appearance inspection, the flat-end sleeve can enter a coating production line and comprises damage inspection, dirt inspection and foreign matter inspection; the sleeve with damages such as collision damage, pit damage, scratch damage, bending damage and the like is prevented from entering a coating production line; the sleeve with greasy dirt on the inner wall can enter a coating production line after being manually cleaned; for the sleeve with the embedded oxide skin on the inner wall, the sleeve can enter a coating production line after the embedded oxide skin is clearly processed.
(2) And (3) derusting the inner wall of the pipe body of the sleeve entering the coating production line, and derusting by using a steel brush power tool to ensure that the derusting quality grade is not lower than St 2.0 and the surface roughness value is not lower than 50 mu m.
(3) The sleeve after rust removal utilizes compressed air to blow the inner wall of the pipe body, and the dust degree is not lower than one level.
(4) The sleeve pipe which is blown by compressed air is coated with an anticorrosive coating by adopting an air pressure liquid spraying mode, the coating speed is about 6 m/min, the single-layer coating is carried out, the relative air humidity of a coating workshop is 90%, the temperature is 20-30 ℃, and the interval time from sand blasting to rust removal to coating is required to be not more than 2 hours; the coating of the anticorrosive layer is a domestic 718 coating (national experimental research on temporary internal protective coating for oil well pipes, great excellence and the like, modern coating and painting, no. 2 in 2015, pages 32-36), and other similar products can be used instead; the anticorrosive coating is a hydrophobic self-healing anticorrosive coating for storage.
(5) And (3) transferring the sleeve coated with the anticorrosive coating to a curing rotary rack for curing the anticorrosive coating, curing the pipe body at normal temperature in the air in a rotating state with the circumferential rotating speed of 1 r/min, wherein the curing time is not less than 30 min, and curing the pipe body until the surface of the inner anticorrosive coating is initially dry (the pipe body is not sticky when being touched by a hand).
(6) And (4) carrying out anticorrosive coating quality inspection on the sleeve after the anticorrosive coating is cured to ensure that no coating leakage and obvious sagging exist, and measuring the thickness of a group of anticorrosive coatings every five groups, wherein the thickness of the anticorrosive coatings is not less than 70 mu m.
(7) And (4) enabling the flat-end sleeve qualified by the quality inspection of the anticorrosive coating to enter a thread processing production line of a sleeve threading factory to prepare for thread processing, coupling screwing and the like.
(8) Processing buttress thread on the end of the sleeve; in the process of machining pipe end threads, fully-synthetic water-based cutting fluid is used, so that an anticorrosive coating is prevented from being damaged (the paint of the anticorrosive coating used in the embodiment belongs to waterproof oil solubility); because the anti-corrosion layer has good temperature resistance and certain damage self-healing property, special temperature control, chip cleaning and protection measures are not carried out in the thread machining process, and the cutting speed is about 200 r/min.
(9) And completing the work of thread inspection, thread grease smearing, coupling screwing, protective cap installation, weighing and length measurement, paint spraying and label spraying, packaging, warehousing and the like.
(10) And finishing the shipment of the finished product in a sleeve threading factory.
The cost of using this example compared to the cost of applying a corrosion protection layer using a conventional process is shown in table 2:
TABLE 2
In the traditional method, the auxiliary procedures (thread pretreatment, post-treatment, packaging protection and the like) account for more than 12 percent of the total cost; compared with the traditional method, the method saves the cost by more than 30 percent and about 7.7 yuan. The product prepared by only the example 1 is supplied by about 20 ten thousand meters in a certain foreign market every year, and the cost can be saved by about 118 ten thousand yuan by adopting the method.
Example 2
The embodiment provides a high temperature resistant type anti-CO of an oil pipe2Anticorrosion coating process in anticorrosion layer
The raw materials used in the process are 73.02mm in outer diameter and 5.51mm in wall thickness, and the L80-1 steel grade flat-end oil pipe has the use working condition temperature of 180 ℃.
The anti-corrosion coating process in the oil pipe comprises the following steps:
(1) After entering a flat-end oil pipe of a coating plant for pipe body appearance inspection, the pipe body can enter a coating production line, and the coating production line comprises damage inspection, dirt inspection and foreign matter inspection; the oil pipe with damages such as collision damage, pit damage, scratch damage, bending damage and the like is prevented from entering a coating production line; the oil pipe with greasy dirt on the inner wall can enter a coating production line after being manually cleaned; and for the oil pipe with the embedded oxide skin on the inner wall, the oil pipe can enter a coating production line after the embedded oxide skin is removed.
(2) Performing shot blasting rust removal on the inner wall of the pipe body of the oil pipe entering the coating production line, and ensuring that the quality grade of rust removal is not lower than Sa 2.5 and the surface roughness value is not lower than 60 mu m.
(3) The oil pipe after rust removal utilizes compressed air to blow the inner wall of the pipe body, so that the dust degree is not lower than two levels.
(4) Coating an anticorrosive coating on the oil pipe subjected to compressed air blowing;
4.1 first the base layer is applied: coating a base layer by adopting an airless rotary liquid spraying mode, and performing double-layer spraying twice, wherein the rotating speed of a spray head is not less than 3000 r/min, the coating speed is about 6 m/min, the relative air humidity of a coating workshop is 70%, the temperature is 15-25 ℃, and the interval time from sand blasting to rust removal to bottom layer coating is not more than 4 hours;
4.2 the oil pipe after the base course coating is transported to the solidification rotating table frame to carry out the base course solidification: curing the pipe body at normal temperature in the air in a rotating state with the circumferential rotating speed of 1 r/min, wherein the curing time is not less than 30 min, and the pipe body is cured until the surface of the inner anti-corrosion layer is initially dry (hands are not sticky when being touched);
4.3 the oil pipe after the base layer is solidified is subjected to base layer quality inspection: ensuring no sagging, measuring the total thickness of a group of base layers by every five base layers, wherein the total thickness of the base layers is not less than 120 mu m, and carrying out full-coverage electric spark leakage point detection on the base layers one by one to ensure no leakage point;
4.4 coating the surface layer of the oil pipe qualified by the base quality inspection: firstly, preheating a pipe body of a spraying section to 260-280 ℃ in a progressive intermediate frequency heating mode (because the pipe body has no precise structures such as threads and the like, the influence of heating temperature on thread precision is not needed to be worried about), and performing surface coating in an electrostatic spraying mode, wherein the coating temperature is ensured to be 220-240 ℃, and the coating speed is about 2 m/min;
4.5, transferring the oil pipe coated with the surface layer to a drying and curing furnace for drying and curing the whole pipe body: the circumferential rotating speed in the pipe body curing furnace is about 3 revolutions per minute, the curing temperature is controlled to be 180-190 ℃, the curing time is not less than 30 minutes, and the anticorrosive coating is completely cured;
CO prevention2The corrosion-resistant layer comprises the base layer and the surface layer, wherein the base layer is a two-component liquid modified epoxy coating (TC 3000F special primer of Shanghai Sai Neen), the surface layer is a melting type epoxy powder coating (TC 3000F coating of Shanghai Saen Neen), and other similar products can be used instead.
(5) And (3) carrying out anticorrosive coating quality inspection on the oil pipe subjected to drying and curing of the whole pipe body to ensure no sagging, measuring the total thickness of a group of anticorrosive coatings every five, wherein the total thickness is not less than 120 mu m, carrying out full-coverage electric spark leakage point detection on the anticorrosive coatings one by one to ensure no leakage point.
(6) And (4) enabling the flat-end oil pipe qualified by the quality inspection of the anticorrosive layer to enter a thread machining production line of an oil pipe threading mill, and preparing for thread machining, coupling screwing and the like.
(7) Carrying out thread machining on the end of an oil pipe; during the process of machining the thread at the end of the pipe, water-based or oil-based cutting fluid can be used (the coating of the anticorrosive coating used in the embodiment is water-resistant and oil-resistant); because the temperature resistance limit of the anticorrosive coating is 180 ℃, the cutting temperature is well controlled in the thread machining process (the cutting speed is controlled at 130 r/min, and the single cutting output/feed amount is not more than 0.3 mm); the coating is easy to suffer from mechanical damage, and a special quick-mounting protective plug (the specific structure is shown in figures 2-3) is arranged at the pipe end before thread processing, so that cutting scraps are prevented from entering the pipe body;
the protective plug is selected from one of a protective plug A, a protective plug B and a protective plug C, and the protective plug A, the protective plug B and the protective plug C are all made of rubber and plastic.
The protective plug a (shown in fig. 2 and 3) includes a sealing portion 2 at the rear end and a friction portion 3 at the front end; the sealing part 2 is cylindrical, and the outer wall of the sealing part is attached to the inner wall of the oil casing so as to seal and attach the sealing part 2 to the inner wall of the oil casing; the friction part 3 is used for being clamped with the inner wall of the oil sleeve, the friction part 3 is provided with an inverted tooth-shaped structure, the inverted tooth-shaped structure is provided with at least one inverted tooth, the tooth top of the inverted tooth is used for being in contact with the inner wall of the oil sleeve, and the diameter of the tooth top circle of the inverted tooth-shaped structure is equal to that of the sealing part 2, so that the chip leakage in the thread machining process is prevented; the sealing part 2 is also provided with a handle 1: the handle 1 is arranged at the rear end of the sealing part, and a groove is formed in the arrangement part of the handle 1 so as to facilitate the holding of the handle and/or the detachment of the protective plug by using a tool; the sealing part and the friction part are integrally formed.
The protector plug B (shown in fig. 4) includes a seal portion 2 at the rear end and a friction portion 3 at the front end; the sealing part 2 is cylindrical, and the outer wall of the sealing part is attached to the inner wall of the oil casing so as to seal and attach the sealing part 2 to the inner wall of the oil casing; the friction part 3 is used for being clamped with the inner wall of the oil sleeve, a thread-shaped structure is arranged on the friction part 3, a surface spiral line of the thread-shaped structure is used for being in contact with the inner wall of the oil sleeve, and the outer diameter of the thread-shaped structure is equal to the diameter of the sealing part 2, so that the chip leakage in the thread machining process is prevented; the sealing part 2 is also provided with a handle 1: the handle 1 is arranged at the rear end of the sealing part, and a groove is formed in the arrangement part of the handle 1 so as to facilitate the holding of the handle and/or the detachment of the protective plug by using a tool; the sealing part and the friction part are integrally formed.
The protective plug C (shown in fig. 5) includes a sealing portion 2 at the rear end and a friction portion 3 at the front end; the sealing part 2 is cylindrical, and the outer wall of the sealing part is used for being attached to the inner wall of the oil sleeve so as to realize the sealing attachment of the sealing part 2 and the inner wall of the oil sleeve; the friction part 3 is used for being clamped with the inner wall of the oil sleeve so as to ensure that cuttings are prevented from leaking in the thread machining process; the sealing part and the friction part are integrally formed.
(8) And finishing the work of thread inspection, thread grease smearing, coupling screwing, protective cap installation, weighing and length measurement, paint spraying and label spraying, packaging, warehousing and the like.
(9) And finishing the shipment of the finished product in an oil pipe threading factory.
Claims (20)
1. An oil casing internal anticorrosion coating process, wherein the process comprises the following steps:
1) Cleaning the inner wall of the flat-end oil casing;
2) After the inner wall of the oil casing pipe is cleaned, coating and curing an anticorrosive coating on the inner wall of the pipe body;
3) Performing thread machining on the pipe end of the oil casing pipe treated in the step 2); in the thread processing process, the highest temperature of the inner wall of the thread processing part is not more than 90% of the upper limit of the temperature resistance of the anticorrosive coating of the pipe body in centigrade; the cutting fluid used for thread processing does not damage the anticorrosive coating coated on the inner wall of the oil sleeve;
if the anti-corrosion layer does not have the function of mechanical damage self-repair, a protective plug is additionally arranged inside the pipe end of the oil casing pipe when the pipe end thread machining is carried out, the protective plug extends into the end face of the oil casing pipe by 0.5cm-1cm, and the protective plug is used for preventing cutting scraps in the thread machining process from entering the inner part of the oil casing pipe body to damage the protective layer; the protective plug includes: a sealing part at the rear end and a friction part at the front end; the sealing part is used for being attached to the inner wall of the oil sleeve in a sealing mode, and the friction part is used for being clamped with the inner wall of the oil sleeve;
wherein, the cutting speed, the single cutting amount and the cutting fluid formula in the process of machining the thread of the oil sleeve with each size are controlled as follows:
Wherein the size of the oil casing is the outer diameter of the oil casing;
4) And after the oil casing pipe end threads are processed, the coupling is screwed down and the pipe end is protected, so that the whole anti-corrosion coating process in the oil casing pipe is completed.
2. The anticorrosive coating process according to claim 1, wherein before the inner wall cleaning treatment of the plain end oil jacket pipe, an appearance inspection is performed, the appearance inspection including inspecting whether the oil jacket pipe body is damaged, whether dirt exists on the inner wall of the oil jacket pipe, and whether foreign matter exists on the inner wall of the oil jacket pipe; if the oil casing body is damaged, the oil casing does not carry out the subsequent steps; if dirt exists on the inner wall of the oil sleeve, cleaning the dirt; and if the oil casing pipe has foreign matters, removing the foreign matters.
3. The anticorrosive coating process according to claim 1, wherein the inner wall cleaning treatment includes an inner wall rust removing treatment and an inner wall purging cleaning.
4. The corrosion protection coating process according to claim 3, wherein:
when the anticorrosive coating to be coated is an anticorrosive coating for temporary storage, the inner wall rust removal treatment is realized by at least one of manual rust removal and power tool rust removal; the derusting grade of the inner wall derusting treatment is not lower than St 2.0 in GB/T8923.1 and/or ISO 8501-1;
when the anticorrosive coating to be coated is other anticorrosive coatings except for the anticorrosive coating for temporary storage, the rust removal treatment is realized by at least one of sand blasting rust removal and shot blasting rust removal; the derusting grade of the inner wall derusting treatment is not lower than Sa 2.5 in GB/T8923.1 and/or ISO 8501-1.
5. The corrosion protection coating process according to claim 3, wherein:
when the anticorrosive coating to be coated is an anticorrosive coating for temporary storage, the dust degree of the inner wall after purging and cleaning meets the requirement of more than grade 2 of GB/T18570.3 and/or ISO 8502-3;
when the anticorrosive coating to be coated is other anticorrosive coatings except for the anticorrosive coating for temporary storage, the dust degree of the inner wall after purging and cleaning can meet the requirement of more than grade 1 of GB/T18570.3 and/or ISO 8502-3.
6. The anticorrosive coating process according to claim 1, wherein, in the anticorrosive coating treatment of the inner wall of the pipe body:
when the anticorrosive coating coated on the inner wall of the oil casing pipe body is not a high-temperature-resistant anticorrosive coating, the coating temperature is not higher than 200 ℃;
when the anticorrosive coating coated on the inner wall of the oil casing pipe body is a high-temperature-resistant anticorrosive coating, preheating the oil casing pipe body and then coating the anticorrosive coating, wherein the preheating temperature is not lower than 260 ℃, and the coating temperature is 220-250 ℃ or not lower than the glass transition temperature of the coating and 20 ℃.
7. The anticorrosion coating process according to claim 1, wherein after the coating treatment and the curing treatment of the anticorrosion layer on the inner wall of the pipe body are carried out on the oil casing pipe, before the thread machining of the end of the oil casing pipe, the quality inspection of the anticorrosion layer is carried out;
and when the quality of the anticorrosive coating of the oil casing is qualified, the oil casing performs subsequent thread processing on the pipe end of the oil casing, and when the quality of the anticorrosive coating is unqualified, the oil casing performs coating treatment on the anticorrosive coating on the inner wall of the pipe body and curing treatment on the anticorrosive coating again.
8. An anti-corrosion coating process according to claim 1, wherein the protective plug is made of a flexible material.
9. The corrosion protective coating process according to claim 8, wherein the flexible material is rubber plastic.
10. The anticorrosive coating process according to claim 1, wherein the sealing portion is further provided with a handle: the handle is arranged at the rear end of the sealing part.
11. A corrosion protective coating process as claimed in claim 10, wherein the sealing portion is provided with a recess at a handle-provided portion to facilitate grasping of the handle and/or removal of the protective plug using a tool.
12. The corrosion protective coating process according to claim 1, wherein the sealing portion is cylindrical, and an outer wall of the sealing portion is configured to be fitted to an inner wall of the oil jacket pipe.
13. The anticorrosive coating process according to claim 1, wherein an inverted tooth-shaped structure is provided on the friction portion; the inverted tooth-shaped structure is provided with m inverted teeth, and tooth tops of the inverted teeth are used for being in contact with the inner wall of the oil sleeve; m is a positive integer greater than 1.
14. The anticorrosive coating process according to claim 13, wherein a tip circle diameter of the inverted tooth profile is equal to a diameter of the sealing portion.
15. The anticorrosion coating process of claim 1 wherein a thread-shaped structure is provided on the friction portion; the surface spiral line of the thread-shaped structure is used for being in contact with the inner wall of the oil sleeve.
16. An erosion protection coating process according to claim 15, wherein the outer diameter of the thread-shaped structure is equal to the diameter of the sealing portion.
17. The corrosion protection coating process according to claim 1, wherein the sealing portion is integrally formed with the friction portion.
18. The anticorrosive coating process according to claim 1, wherein the oil casing is subjected to a thread inspection after the oil casing is subjected to the oil casing pipe end thread machining, before the coupling tightening and the pipe end protection; and when the thread is detected to be qualified, performing subsequent steps on the oil casing, and when the thread is detected to be unqualified, removing the unqualified thread section by adopting a mechanical cold cutting mode and then re-processing the thread at the end of the oil casing.
19. The anti-corrosion coating process according to claim 1, wherein after the oil casing pipe is subjected to collar tightening and pipe end protection, the whole body of the oil casing pipe and a collar end are subjected to a drift diameter inspection, and the drift diameter inspection meets the requirement of API SPEC.5CT, wherein a drift diameter rod used for the drift diameter inspection is a plastic drift diameter rod.
20. The anticorrosion coating process as claimed in claim 1, wherein the process further comprises step 5) of weighing, measuring length, packaging and warehousing the oil casing after the coupling is screwed and the pipe end is protected; wherein the packaging comprises painting on the outer surface of the oil casing pipe body and spraying the mark of the pipe body.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910839439.6A CN112439678B (en) | 2019-09-03 | 2019-09-03 | Anticorrosion coating process in oil casing |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910839439.6A CN112439678B (en) | 2019-09-03 | 2019-09-03 | Anticorrosion coating process in oil casing |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN112439678A CN112439678A (en) | 2021-03-05 |
| CN112439678B true CN112439678B (en) | 2022-11-01 |
Family
ID=74733394
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910839439.6A Active CN112439678B (en) | 2019-09-03 | 2019-09-03 | Anticorrosion coating process in oil casing |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112439678B (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113578718A (en) * | 2021-06-07 | 2021-11-02 | 刘沙 | Inner wall anticorrosion technology suitable for thin and short HDPE corrugated pipe |
| CN113399389A (en) * | 2021-06-28 | 2021-09-17 | 烟台杰瑞石油装备技术有限公司 | Coiled tubing corrosion prevention method, purging device and operation equipment |
| CN113856938B (en) * | 2021-11-29 | 2022-03-04 | 单县多米石墨烯科技有限公司 | A kind of spraying uniformity detection method and system of graphene anti-corrosion coating |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101082269A (en) * | 2006-05-30 | 2007-12-05 | 天津钢管集团有限公司 | Petroleum annular tube reducer union and production process |
| CN102003148A (en) * | 2010-09-17 | 2011-04-06 | 北京百利时能源技术有限责任公司 | Oil casing pipe resisting CO2 corrosion and production method thereof |
| CN103883261A (en) * | 2014-03-21 | 2014-06-25 | 盘锦中际特种管材制造有限公司 | Ten-meter long silicate compound oil casing pipe and manufacturing method |
| CN106051371A (en) * | 2016-08-09 | 2016-10-26 | 北京市城南橡塑技术研究所 | Composite structure sealing plug for pipe |
| CN205877576U (en) * | 2016-08-09 | 2017-01-11 | 北京市城南橡塑技术研究所 | Composite construction sealing plug for pipeline |
| CN206001188U (en) * | 2016-07-19 | 2017-03-08 | 中国一冶集团有限公司 | A kind of closing device for protective conduit clean cavity degree |
| CN109161788A (en) * | 2018-08-06 | 2019-01-08 | 中国石油天然气集团有限公司 | A kind of heat injection steam thick oil thermal extraction high temperature resistant petroleum casing pipe and its manufacturing method |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5028923B2 (en) * | 2006-09-14 | 2012-09-19 | 住友金属工業株式会社 | Threaded joints for steel pipes |
| JP4924103B2 (en) * | 2007-03-02 | 2012-04-25 | 住友金属工業株式会社 | Threaded joint for oil well pipe |
| AR106975A1 (en) * | 2015-12-25 | 2018-03-07 | Nippon Steel & Sumitomo Metal Corp | THREADED CONNECTION FOR PIPE OR PIPE AND METHOD TO PRODUCE THE THREADED CONNECTION FOR PIPE OR TUBE |
-
2019
- 2019-09-03 CN CN201910839439.6A patent/CN112439678B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101082269A (en) * | 2006-05-30 | 2007-12-05 | 天津钢管集团有限公司 | Petroleum annular tube reducer union and production process |
| CN102003148A (en) * | 2010-09-17 | 2011-04-06 | 北京百利时能源技术有限责任公司 | Oil casing pipe resisting CO2 corrosion and production method thereof |
| CN103883261A (en) * | 2014-03-21 | 2014-06-25 | 盘锦中际特种管材制造有限公司 | Ten-meter long silicate compound oil casing pipe and manufacturing method |
| CN206001188U (en) * | 2016-07-19 | 2017-03-08 | 中国一冶集团有限公司 | A kind of closing device for protective conduit clean cavity degree |
| CN106051371A (en) * | 2016-08-09 | 2016-10-26 | 北京市城南橡塑技术研究所 | Composite structure sealing plug for pipe |
| CN205877576U (en) * | 2016-08-09 | 2017-01-11 | 北京市城南橡塑技术研究所 | Composite construction sealing plug for pipeline |
| CN109161788A (en) * | 2018-08-06 | 2019-01-08 | 中国石油天然气集团有限公司 | A kind of heat injection steam thick oil thermal extraction high temperature resistant petroleum casing pipe and its manufacturing method |
Also Published As
| Publication number | Publication date |
|---|---|
| CN112439678A (en) | 2021-03-05 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN112439678B (en) | Anticorrosion coating process in oil casing | |
| CN103946617A (en) | Tubular threaded joint having improved high torque performance | |
| CN104043941B (en) | Re-manufacturing machining process of surface of inner hole of hydraulic cylinder scrap guide sleeve | |
| CN103170444B (en) | Airless spraying corrosion resistance technology for inner wall and outer wall of oil pipe | |
| CN104785404A (en) | Ship steel materials pretreatment device | |
| CN104334952A (en) | Threaded joint for steel pipe | |
| CN104148268A (en) | Surface processing method of steel structure part | |
| CN102699617A (en) | Remanufacturing method for waste oil tubes | |
| CN101992424A (en) | Treatment process for inner surface of tube for oil production | |
| CN109877021A (en) | A kind of preparation method of oil/gas well anti-corrosion wax control tubing | |
| US20090008087A1 (en) | Threaded joint for an oil-well tubing | |
| US20160305651A1 (en) | Ceramic coating and process for applying the same | |
| CN109854863A (en) | A kind of buried pipeline repairing anticorrosion coating external member and construction method | |
| US10920913B2 (en) | Premium threaded connection and method for making same | |
| CN114182248A (en) | Cold spraying repair and protection method for corrosion of hole bottom of flange plate | |
| CN1704639A (en) | Three-layer structured polypropylene anticorrosive technology for steel buried transportation pipe | |
| CN110385247A (en) | A kind of cigarette air channel barrier door nanometer heavy antisepsis technique | |
| CN105333238B (en) | Metal ceramic composite oil pipe manufactured by remanufacturing waste oil pipe and remanufacturing process thereof | |
| CN104368513A (en) | Inner wall anti-corrosion method of petroleum drill collar | |
| CN105925928A (en) | Surface treatment method for blade of large turbine machine | |
| CN105290706B (en) | A kind of method for maintaining of grease lubrication formula shaft coupling | |
| CN201534302U (en) | Inner surface processing device for oil exploitation pipe | |
| CN105290705B (en) | A kind of method for maintaining of oil lubricating type shaft coupling | |
| CN110860448A (en) | Novel polyurethane coating process for nodular cast iron pipe fitting | |
| CN109483162A (en) | A kind of tile manufacture craft |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |