CN212672608U - Thermal cladding high-molecular polyolefin composite inner anti-corrosion protection ground engineering pipeline - Google Patents
Thermal cladding high-molecular polyolefin composite inner anti-corrosion protection ground engineering pipeline Download PDFInfo
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- CN212672608U CN212672608U CN202021067792.1U CN202021067792U CN212672608U CN 212672608 U CN212672608 U CN 212672608U CN 202021067792 U CN202021067792 U CN 202021067792U CN 212672608 U CN212672608 U CN 212672608U
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Abstract
The utility model relates to a hot cladding polymer polyolefin composite inner anti-corrosion protection ground engineering pipeline. Mainly solves the problems that the traditional liquid epoxy anticorrosive coating and fused epoxy powder anticorrosive coating have thin thickness, low mechanical strength of the coating, poor adhesion of polyolefin directly contacting with the pipe and low recycling rate of waste oil pipe repair. The method is characterized in that: the inner surface of the steel pipe (1) is sequentially provided with a primer layer (2) and a high-molecular polyolefin composite protective layer (3); the outer surface of the steel pipe (1) is provided with an outer protective layer (4). This anticorrosive protection ground engineering pipeline in compound of hot cladding polymer polyolefin, primer layer and polyolefin layer structure as an organic whole, thickness is adjustable, can strengthen the pipeline corrosion resistance, adapts to the complicated transport medium of oil field water drive, polymer flooding and ternary complex flooding and corrodes the operating mode, is applied to oil collecting, ternary and pours into the pipeline into, improves pipeline life to can more effectually recycle the old and useless oil pipe after the restoration.
Description
Technical Field
The utility model relates to a pipeline, especially a hot cladding polymer polyolefin composite inner anti-corrosion protection ground engineering pipeline in the oil field pipeline anti-corrosion processing special manufacturing field.
Background
The buried pipeline is one of the important facilities of ground engineering as the transmission carrier of oil gas. The pipeline is a link for connecting upstream resources with downstream users, and due to the fact that the pipeline is buried underground for a long time, as time goes on, the external soil characteristics and the influence of factors such as terrain settlement and the like, different types (water drive, polymer drive and ternary) of oil collection and injection pipelines are complex in corrosive media, the working condition environment is severe, the pipelines are prone to corrosion, perforation and leakage, and serious loss is brought to oil fields and countries. According to statistics, various pipelines are built in Daqing oil fields for more than 10 thousands kilometers at present, and the annual failure rate of the pipelines in the oil fields in 2019 is 0.461 times/kilometer. The pipeline conveying medium and the composite flooding medium are complex, so that the internal corrosion factors are more and the corrosion is aggravated.
Economic losses caused by construction and corrosion of oil and gas pipelines can be divided into direct losses and indirect losses. The direct loss comprises the cost of replacing equipment and components, the cost of repairing and preventing corrosion, the indirect loss comprises the loss caused by shutdown loss, product loss caused by corrosion leakage, corrosion product accumulation or corrosion damage, and the indirect loss is far greater than the direct loss and is difficult to estimate. Besides considering the serious economic loss caused by the corrosion of the pipeline, the corrosion of the pipeline can cause the leakage of harmful substances, cause pollution to the environment and even cause sudden disastrous accidents to endanger the personal safety.
The traditional liquid epoxy anticorrosive coating and the fused epoxy powder anticorrosive coating which are commonly adopted at present have the defects of thin thickness, low mechanical strength of the coating, coating defects and poor adhesion of polyolefin in direct contact with a pipe.
In recent years, international oil prices are continuously in low loitering, and most domestic oil and gas field enterprises face greater operating pressure. The waste oil pipe is repaired and reused to become an important measure for realizing upgrading and efficiency enhancement of the oil field and realizing a low-cost development strategy.
The oil pipe is used as a main channel for oil and gas production, and is subjected to various external force damages in an oil well besides the corrosion of various corrosive media in crude oil. Generally, after a period of production, the oil pipe passage is easily waxed and scaled to cause the blockage of the main passage, and the rod pipe is eccentrically worn to cause the leakage of the oil pipe, thereby affecting the normal production of the oil well. The research on the existing common waste oil pipe repairing technology comprises three types: (1) simple repair (replacement of coupling, re-machining of threads, short section machining, etc.); (2) remanufacturing (hot rolling repair, self-propagating high-temperature synthesis, etc.); (3) and (4) making a ground pipeline (directly used after cleaning, used after repairing the lining, and the like). And aiming at the third type of old oil pipes, screening according to the critical wall thickness of the ground pipeline, thermally coating the inner lining high-molecular polyethylene composite anticorrosive protective layer, and performing field application again after repairing to save the cost of the oil field pipes.
Disclosure of Invention
The utility model aims to solve the technical problem that overcome the current traditional liquid epoxy anticorrosive coating of adoption and the problem that the sintering epoxy powder anticorrosive coating has thickness thin in the background art, coating mechanical strength is low, polyolefin is direct and the poor and old and useless oil pipe of tubular product contact adhesiveness restores and recycles low, and provide a hot cladding polymer polyolefin compound interior anti-corrosion protection ground engineering pipeline, this hot cladding polymer polyolefin compound interior anti-corrosion protection ground engineering pipeline, can strengthen pipeline corrosion resistance, adapt to oil field water drive, gather and drive and the complicated transport medium of ternary complex flooding and corrode the operating mode, be applied to oily and injection pipeline, improve pipeline life, and can more effectually recycle old and useless oil pipe after the restoration.
The utility model provides a its problem accessible reach as follows technical scheme: the hot-melt-coated high-polymer polyolefin composite inner anti-corrosion protection ground engineering pipeline comprises a steel pipe, wherein after the inner wall and the outer wall of the steel pipe are pretreated, a primer layer and a polyolefin protection layer are sequentially manufactured on the inner surface of the steel pipe; the outer surface of the steel pipe is provided with an outer protective layer.
The outer protective layer can be a two-layer structure and a three-layer structure (injection pipeline) or a hard polyurethane heat-insulating material layer (gathering and transportation pipeline). The bottom layer of the two-layer structure is an adhesive layer, and the outer layer is a polyethylene layer; the bottom layer of the three-layer structure is usually an epoxy powder coating, the middle layer is an adhesive layer, and the outer layer is a polyethylene layer. The hard polyurethane heat-insulating material layer comprises a primer layer, an adhesive tape layer, a foam layer and a polyethylene layer; the bottom glue layer is an adhesive layer.
The bottom glue layer and the polyolefin protective layer are hot-melt-coated one-step-formed composite protective layers. The inner wall of the steel pipe is coated with the hot-melt high-polymer polyolefin protective layer, and a seamless-connection special coupling is combined to form the three-layer seamless steel-plastic composite oil pipe, so that the whole pipeline has no steel exposed point, and has the functions of long-acting wear resistance, corrosion resistance, wax deposition resistance and no scale formation. The product integrates the eccentric wear resistance and the corrosion resistance; the inner wall and the outer wall of the steel pipe are made of high-toughness high-strength wear-resistant materials, and the inner wall plastic layer and the outer wall plastic layer are hot-melted together with the oil pipe and do not fall off or peel off; the lining pipe material has high strength, can not cause accidents due to the generation of small holes, cracks, fracture, peeling and the like, and can not expand, shrink or pack; the inner hot melting cladding layer has elastoplasticity, self-adjusting and self-repairing performance, and has synergistic effect and memory effect, the inner pipe adapts to the steel pipe stretching deformation generated by temperature change and stress change, and the inner pipe is kept not to fall off and not to peel off on the inner surface of the steel pipe; the service life of the pipeline can be prolonged by 5-7 times.
Compared with the above background art, the utility model can have following beneficial effect: compared with the existing anti-corrosion pipeline, the hot-melt-coated high-polymer polyolefin composite inner anti-corrosion protection ground engineering pipeline has the following advantages:
1) strong viscosity, self fusion, water and gas permeation resistance and good sealing performance.
2) High electric insulating property, excellent ageing-resistant stability and strong ultraviolet radiation resistance.
3) Has the capability of resisting the soil stress damage and strong impact resistance.
4) The working efficiency is improved, the material is greatly saved, the cost is reduced, and the construction is convenient.
5) The interior is smooth, reduces friction, and the drainage speed is fast.
6) Can be applied to both new carbon steel pipes and old oil pipes.
The pipeline internal surface adopts hot cladding polymer polyolefin combined material as anticorrosive protective layer, including gluing agent layer and polyolefin layer in the composite bed structure, the two is compound together, in the pipeline course of working, gluing agent layer hot melt, one side and pipeline zonulae occludens, one side polyolefin layer fuses, play the zonulae occludens effect, polymer polyolefin layer has good corrosion resistance, adapt to the oil field water drive, gather and drive the complicated transport medium corrosion operating mode of three-component complex flooding, thickness 3~4 mm, high strength, increase surface finish simultaneously, the medium flow resistance is littleer, corrosion resistance reinforcing, wear resistance promotes. The thermal melting coating macromolecule polyolefine composite material has the expansion coefficient similar to that of steel, and the thermal melting coating layer is completely combined with the inner wall of the pipe without gaps. The defects of thin thickness, low mechanical strength of the coating, coating defect and poor adhesion of direct contact between polyolefin and the pipe in the traditional liquid epoxy anticorrosive coating and fused epoxy powder anticorrosive coating are overcome, the protective performance of the product is improved, and the service life of the steel pipe is prolonged. The outer surface adopts two-layer structure polyethylene, three-layer structure polyethylene or hard polyurethane thermal insulation material as an outer protective layer, and is applied to oil collection and injection pipelines. The utility model discloses but wide application buries the outer anticorrosive and old oil pipe repair engineering of holding vessel body in plumbing and oil gas, coal gas conveying steel pipeline and the steel in oil, natural gas, chemical industry, urban construction. Is a latest pollution-free and harmless environment-friendly anticorrosion process product.
Description of the drawings:
FIG. 1 is a schematic structural diagram of the present invention;
FIG. 2 is a flow chart of the thermal-coating polymer polyolefin composite internal corrosion prevention process of the present invention;
FIG. 3 is the process of the outer surface three-layer structure polyethylene layer of the utility model;
FIG. 4 is a process of the outer surface hard polyurethane foam plastic anti-corrosion heat-insulating layer of the utility model;
figure 5 is the surface two-layer structure polyethylene layer process of the utility model.
In the figure: 1-steel pipe protective layer, 2-primer layer, 3-high molecular polyolefin protective layer, and 4-outer protective layer.
The specific implementation mode is as follows:
the invention will be further explained with reference to the drawings:
as shown in fig. 1, the hot-melt coated high polymer polyolefin composite inner anti-corrosion protection ground engineering pipeline comprises a steel pipe 1, wherein after the inner wall and the outer wall of the steel pipe 1 are pretreated, a primer layer 2 and a high polymer polyolefin protection layer 3 are sequentially manufactured on the inner surface of the steel pipe 1; the outer surface of the steel pipe 1 is provided with an outer protective layer 4, the outer protective layer 4 can be a two-layer polyethylene layer, a three-layer polyethylene layer or a hard polyurethane heat-insulating material layer, and the thickness is uniform and consistent; the primer layer 2 is an adhesive layer, the adhesive layer is hot-melted, one side of the adhesive layer is tightly connected with the pipeline, the other side of the adhesive layer is fused with the polyolefin protective layer, the tight connection effect is achieved, and the high-molecular polyolefin layer has good corrosion resistance and is suitable for corrosion working conditions of complex conveying media of oil field water flooding, polymer flooding and ternary combination flooding.
The surface of the steel pipe can be pretreated by a chemical method or a sintering method, the sand blasting can be general quartz sand, or the sand blasting can be performed by steel sand blasting, steel shot blasting or dry-wet method sand blasting, the extrusion can be performed by an extruder, the heating can be performed by a medium frequency mode, and the detection can be performed by a professional thickness gauge. The outer wall is formed into a V shape by adopting a beveling machine, the bevel angle is 30-35 degrees, the truncated edge is less than 1.0mm, and the surface of the pipe is cleaned by a shot blasting method to reach the standard of rust removal, and the standard is Sa2.5 grade.
The protective layer of the inner layer of the anti-corrosion steel pipe is improved into a hot-melt-coated high-molecular-polyolefin composite inner anti-corrosion protective anti-corrosion layer, the high-molecular-polyolefin layer has good corrosion resistance, is suitable for corrosion working conditions of complex conveying media of water drive, polymer drive and ASP flooding in an oil field, has the thickness of 3-4 mm and high strength, and simultaneously increases the surface smoothness, the flow resistance of the media is smaller, the corrosion resistance is enhanced, and the wear resistance is improved. The thermal melting coating macromolecule polyolefine composite material has the expansion coefficient similar to that of steel, and the thermal melting coating layer is completely combined with the inner wall of the pipe without gaps. The defects of thin thickness, low mechanical strength of the coating, coating defect and poor adhesion of direct contact between polyolefin and the pipe in the traditional liquid epoxy anticorrosive coating and fused epoxy powder anticorrosive coating are overcome, the protective performance of the product is improved, and the service life of the steel pipe is prolonged.
The heat-cladding high-molecular polyolefin composite inner anti-corrosion protection ground engineering pipeline has the following treatment process of the coatings on the inner surface and the outer surface of the steel pipe 1:
firstly, a flow chart of the steel pipe 1 hot-melt coating high-molecular polyolefin composite internal corrosion prevention process is shown in fig. 2, and the specific process comprises the following steps:
1. and (4) pre-screening the steel pipes of the pipelines (the new carbon steel pipe and the old oil pipe), and checking the appearance and the size.
2. The old oil pipe is cleaned by heat to remove oil contamination and impurities.
3. Internal rust removal, complete internal surface pretreatment and rust removal grade reaching Sa2.5 grade.
4. And blowing, namely blowing the floating ash and impurities on the surface of the pipeline.
5. The high molecular polyolefin composite pipe behind the composite adhesive primer layer 2 is inserted in the pipe, and a special reducing device is adopted to ensure that the high molecular polyolefin composite pipe is inserted in the steel pipe.
6. And (3) carrying out hot cladding and solidification on the lining pipe, adopting a hot cladding device to heat, clad and adhere the polymer polyolefin composite pipe to the inner surface of the steel pipe, and rapidly cooling the steel pipe so that the polymer polyolefin composite pipe and the steel pipe are firmly adhered together.
Secondly, the process flow chart of the polyethylene layer with the three-layer structure on the outer surface of the steel pipe 1 is shown in figure 3, and the specific process flow is as follows:
1. surface pretreatment, cleaning rust and dirt on the surface of the pipeline.
2. And (3) preheating the steel pipe, wherein the preheating temperature and the thickness of each layer of the anticorrosive coating are respectively and sequentially regulated on a production line by using a test pipe section, and the steel pipe can be produced after all parameters meet the requirements.
3. And in the corrosion prevention process, the steel pipe is heated to a proper coating temperature, and the epoxy powder coating is uniformly coated on the surface of the steel pipe. The adhesive must be applied during the ungelled process of the epoxy powder.
The polyethylene of the overlapped part of the longitudinal extrusion process or the lateral winding process and the polyethylene at the two sides of the welding seam are completely rolled and compacted.
4. Cooling, after coating polyethylene, cooling with water until the temperature of the steel pipe is not higher than 60 ℃.
5. The reserved length of the pipe end is 100mm-150mm after the polyethylene layer at the pipe section part is removed, and the end face of the polyethylene layer is chamfered at an angle of less than or equal to 30 degrees.
6. And the electric leakage of the anticorrosive layer is detected by an online electric spark leak detector.
Thirdly, a process flow chart of the hard polyurethane foam plastic anti-corrosion heat-insulation layer on the outer surface of the steel pipe 1 is shown in fig. 4, and the specific process flow is as follows:
1. and (3) surface treatment, wherein the surface attachments on the surface of the pipe are removed by a shot blasting method, and the surface attachments are not lower than grade Sa2 when meeting the standard of rust removal.
2. And (3) coating an anticorrosive layer, coating the anticorrosive layer on the surface of the pipe, wherein the anticorrosive layer is made of the same material as the design, and the thickness is specified according to the standard requirement of a product or the requirement of a user.
3. And (4) winding the adhesive tape according to the design requirement, wherein the overall winding lap joint of the adhesive tape is not less than 10 mm.
4. The heat preservation and protection layer is formed by extruding polyethylene in an extruder at the temperature of about 205 ℃, the polyethylene is plasticized best at the temperature, and the production efficiency is highest. The polyisocyanate and the combined polyether are properly mixed by a proportioning pump in the proportion of [ (1.0-1.1):1.0] and the air pressure of a spray gun is more than 0.5 mPa.
5. Cooling, cooling the antiseptic heat preservation pipe with clear water below 20 ℃.
6. And the deviation rectifying ring is positioned 50-100mm behind the foam liquid level, and the deviation rectifying effect is best.
7. And (3) cutting the joint, wherein the distance between the joint cutting point and the composite machine head is larger than 7m, and a section of light pipe head is reserved at the two ends of the steel pipe, and the length is preferably 150 mm.
8. And (3) baking the waterproof cap, wherein the lap joint part of the waterproof cap and the protective layer pipe wall is cleaned, the specification of the waterproof cap is matched with the pipe diameter, the waterproof cap is heated by a flame heater, and the heating temperature is controlled according to the specification of the waterproof cap product.
9. And (4) inspecting, wherein the thickness deviation of the protective layer and the heat-insulating layer is detected, and the surface of the protective layer is smooth and flat without the defects of dark bubbles, pockmarks, cracks and the like. The heat-insulating layer is filled with steel pipes and a protective annular space, so that the defects of cracking, foam hole stripes, delaminating, shrinking and the like are overcome, and the waterproof cap, the protective layer and the anticorrosive layer are well combined.
Fourthly, the process flow chart of the two-layer structure polyethylene layer on the outer surface of the steel pipe 1 is shown in figure 5, and the specific process flow is as follows:
1. surface pretreatment, cleaning rust and dirt on the surface of the pipeline.
2. And (3) preheating the steel pipe, wherein the preheating temperature and the thickness of each layer of the anticorrosive coating are respectively and sequentially regulated on a production line by using a test pipe section, and the steel pipe can be produced after all parameters meet the requirements.
3. In the anticorrosion process, an extruder, a longitudinal extrusion process or a lateral winding process is adopted for coating the adhesive, and polyethylene at the lap joint part and polyethylene at the two sides of the welding seam are adopted.
4. Cooling, after coating polyethylene, cooling with water until the temperature of the steel pipe is not higher than 60 ℃.
5. The reserved length of the pipe end is 100mm-150mm after the polyethylene layer at the pipe section part is removed, and the end face of the polyethylene layer is chamfered at an angle of less than or equal to 30 degrees.
6. And the electric leakage of the anticorrosive layer is detected by an online electric spark leak detector.
Claims (6)
1. The utility model provides a compound interior anticorrosive protection ground engineering pipeline of hot cladding polymer polyolefin, includes steel pipe (1), its characterized in that: the inner surface of the steel pipe (1) is sequentially provided with a primer layer (2) and a high-molecular polyolefin composite protective layer (3); the outer surface of the steel pipe (1) is provided with an outer protective layer (4).
2. The heat-coated high-molecular polyolefin composite internal-corrosion-prevention protective ground engineering pipeline according to claim 1, characterized in that: the outer protective layer (4) can be a two-layer structure protective layer, a three-layer structure protective layer or a hard polyurethane heat-insulating material layer; the bottom glue layer (2) is an adhesive layer.
3. The hot-melt coated high-molecular polyolefin composite internal anti-corrosion protective ground engineering pipeline as claimed in claim 2, characterized in that: the base adhesive layer (2) and the high-molecular polyolefin protective layer are hot-melt-coated one-step-formed composite protective layers.
4. The hot-melt coated high-molecular polyolefin composite internal anti-corrosion protective ground engineering pipeline as claimed in claim 2, characterized in that: the bottom layer of the two-layer structure protective layer is an adhesive layer, and the outer layer is a polyethylene layer; the bottom layer of the protective layer with the three-layer structure is an epoxy powder coating, the middle layer is an adhesive layer, and the outer layer is a polyethylene layer; the hard polyurethane heat-insulating material layer comprises a primer layer, an adhesive tape layer, a foam layer and a polyethylene layer.
5. The hot-melt coated high-molecular polyolefin composite inner anti-corrosion protective ground engineering pipeline as claimed in claim 1 or 2, wherein: the inner wall and the outer wall of the steel pipe (1) are pretreated.
6. The hot-melt coated high-molecular polyolefin composite inner anti-corrosion protective ground engineering pipeline as claimed in claim 1 or 2, wherein: the steel pipe (1) can be repaired by an old oil pipe or a new carbon steel pipe.
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| CN202021067792.1U CN212672608U (en) | 2020-06-11 | 2020-06-11 | Thermal cladding high-molecular polyolefin composite inner anti-corrosion protection ground engineering pipeline |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113700984A (en) * | 2021-07-14 | 2021-11-26 | 云南智仁节能环保工程有限公司 | Integrated customizable composite heat-insulating pipe and production method thereof |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113700984A (en) * | 2021-07-14 | 2021-11-26 | 云南智仁节能环保工程有限公司 | Integrated customizable composite heat-insulating pipe and production method thereof |
| CN113700984B (en) * | 2021-07-14 | 2023-01-31 | 云南智仁节能环保工程有限公司 | Integrated customizable composite heat-insulating pipe and production method thereof |
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