CN111998142A - Production process of wound 3PE faucet steel pipe - Google Patents
Production process of wound 3PE faucet steel pipe Download PDFInfo
- Publication number
- CN111998142A CN111998142A CN202010942774.1A CN202010942774A CN111998142A CN 111998142 A CN111998142 A CN 111998142A CN 202010942774 A CN202010942774 A CN 202010942774A CN 111998142 A CN111998142 A CN 111998142A
- Authority
- CN
- China
- Prior art keywords
- steel pipe
- bell
- spigot
- powder
- 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.)
- Pending
Links
- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 73
- 239000010959 steel Substances 0.000 title claims abstract description 73
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 19
- 239000000843 powder Substances 0.000 claims abstract description 43
- 239000004593 Epoxy Substances 0.000 claims abstract description 27
- 238000010438 heat treatment Methods 0.000 claims abstract description 18
- 239000007921 spray Substances 0.000 claims abstract description 13
- 238000005260 corrosion Methods 0.000 claims abstract description 11
- 238000000034 method Methods 0.000 claims abstract description 8
- 239000000853 adhesive Substances 0.000 claims abstract description 7
- 230000001070 adhesive effect Effects 0.000 claims abstract description 7
- 238000002844 melting Methods 0.000 claims abstract description 5
- 230000008018 melting Effects 0.000 claims abstract description 5
- 230000003749 cleanliness Effects 0.000 claims abstract description 3
- 239000000428 dust Substances 0.000 claims abstract description 3
- 239000002184 metal Substances 0.000 claims abstract description 3
- 239000003973 paint Substances 0.000 claims abstract description 3
- 238000005507 spraying Methods 0.000 claims description 24
- 239000004698 Polyethylene Substances 0.000 claims description 12
- 239000011248 coating agent Substances 0.000 claims description 12
- 238000000576 coating method Methods 0.000 claims description 12
- 239000010410 layer Substances 0.000 claims description 12
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 10
- 238000004804 winding Methods 0.000 claims description 7
- -1 polyethylene Polymers 0.000 claims description 6
- 229920000573 polyethylene Polymers 0.000 claims description 6
- 238000001816 cooling Methods 0.000 claims description 3
- 238000001514 detection method Methods 0.000 claims description 3
- 238000001125 extrusion Methods 0.000 claims description 3
- 239000012790 adhesive layer Substances 0.000 claims description 2
- 238000007590 electrostatic spraying Methods 0.000 claims description 2
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 abstract description 3
- 238000004321 preservation Methods 0.000 abstract description 2
- 230000007797 corrosion Effects 0.000 description 6
- 238000005536 corrosion prevention Methods 0.000 description 5
- 238000005516 engineering process Methods 0.000 description 5
- 230000000694 effects Effects 0.000 description 4
- 238000010288 cold spraying Methods 0.000 description 3
- 238000010276 construction Methods 0.000 description 2
- 230000004927 fusion Effects 0.000 description 2
- 238000003754 machining Methods 0.000 description 2
- 239000004033 plastic Substances 0.000 description 2
- 229920003023 plastic Polymers 0.000 description 2
- 239000000047 product Substances 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 238000010521 absorption reaction Methods 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 230000004075 alteration Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000010292 electrical insulation Methods 0.000 description 1
- 230000003628 erosive effect Effects 0.000 description 1
- 239000007888 film coating Substances 0.000 description 1
- 238000009501 film coating Methods 0.000 description 1
- 239000003292 glue Substances 0.000 description 1
- 238000009413 insulation Methods 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000003960 organic solvent Substances 0.000 description 1
- 238000005498 polishing Methods 0.000 description 1
- 229920000098 polyolefin Polymers 0.000 description 1
- 238000003303 reheating Methods 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 239000013589 supplement Substances 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
- F16L9/00—Rigid pipes
- F16L9/16—Rigid pipes wound from sheets or strips, with or without reinforcement
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
- F16L58/00—Protection of pipes or pipe fittings against corrosion or incrustation
- F16L58/02—Protection of pipes or pipe fittings against corrosion or incrustation by means of internal or external coatings
- F16L58/04—Coatings characterised by the materials used
- F16L58/10—Coatings characterised by the materials used by rubber or plastics
- F16L58/1009—Coatings characterised by the materials used by rubber or plastics the coating being placed inside the pipe
- F16L58/1027—Coatings characterised by the materials used by rubber or plastics the coating being placed inside the pipe the coating being a sprayed layer
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Rigid Pipes And Flexible Pipes (AREA)
- Application Of Or Painting With Fluid Materials (AREA)
Abstract
The invention relates to the technical field of production processes of bell and spigot 3PE anti-corrosion pipes for pipeline transportation, and discloses a production process of a wound 3PE bell and spigot steel pipe, which comprises the following steps: the method comprises the steps of heating a steel pipe end of a bell and spigot steel pipe at medium frequency, heating the steel pipe end to 850-950 ℃, heating the steel pipe end to 400mm in length, improving the metal fluidity and plasticity of the pipe end, optimizing the structure of steel, processing the bell and spigot, processing the steel pipe into the required pipe end bell and spigot steel pipe through special equipment, performing heat preservation operation in the bell and spigot processing process, removing rust outside the bell and spigot steel pipe, removing oxide skin in bell and spigot processing, increasing the adhesive force of epoxy powder or cold spray paint, enabling the anchor line depth, the dust degree and the cleanliness of the surface of the steel pipe to meet specified requirements, heating the powder at medium frequency, enabling the epoxy powder to be coated on the pipe wall of the steel pipe in a melting mode, and heating the steel pipe to the powder melting temperature of about 210 ℃.
Description
Technical Field
The invention relates to the technical field of production processes of bell and spigot 3PE anti-corrosion pipes for pipeline transportation, in particular to a production process of a wound 3PE bell and spigot steel pipe.
Background
The 3PE anticorrosive steel pipe is a polyolefin coating outer anticorrosive steel pipe with a three-layer structure, and is also a common anticorrosive pipeline, one layer is epoxy powder, the other layer is provided with an adhesive, the three layers are polyethylene, the processing mode is generally divided into two types, one type is a winding type, the other type is a circular film coating type, the winding type has more advantages than the coating type, and the 3PE generally refers to a winding type production mode.
The 3PE integrates the excellent properties of the fusion epoxy powder coating and the extruded polyethylene anticorrosive layer, combines the advantages of the interface property and the chemical resistance of the fusion epoxy powder coating with the advantages of the mechanical protection property of the extruded polyethylene anticorrosive layer, and the like, thereby obviously improving the respective properties, the 3PE can ensure that the service life of a buried pipeline reaches 50 years, the 3PE anticorrosive steel pipe has excellent low-temperature resistance, good chemical stability and resistance to most of acid and alkali erosion, is insoluble in common solvents at normal temperature, has small water absorption, but can be slowly dissolved in certain organic solvents due to linear molecules, does not swell, has excellent electrical insulation property, has good heat insulation property, has heat loss of only twenty-five percent of that of the traditional pipe, can save great resources after long-term operation, obviously reduces the operation cost, and has stronger waterproof and corrosion resistance, at present, no mature bell and spigot steel pipe anticorrosion production technology exists in the market, only part of bell and spigot plastic-coated or epoxy anticorrosion steel pipes exist, but the performance indexes of the bell and spigot plastic-coated or epoxy anticorrosion steel pipes completely do not reach the 3PE anticorrosion effect, and if a production process and a product which combine the advantages of connection of 3PE and bell and spigot are developed, the anticorrosion performance of a pipeline and the flexibility of field construction can be greatly improved.
Disclosure of Invention
Technical problem to be solved
Aiming at the defects of the prior art, the invention provides a production process of a wound 3PE bell and spigot steel pipe, which has the advantages of corrosion resistance of the bell and spigot 3PE steel pipe and the like, and solves the problem of poor corrosion resistance effect of the bell and spigot 3PE steel pipe.
(II) technical scheme
In order to realize the purpose of corrosion prevention of the 3PE steel pipe with the bell and spigot, the invention provides the following technical scheme: a production process of a wound 3PE bell and spigot steel pipe comprises the following steps:
1) and the bell and spigot steel pipe is subjected to bell and spigot intermediate frequency heating, so that the metal fluidity and plasticity of the pipe end are improved, and the structure of steel is optimized.
2) And (4) bell and spigot processing, namely processing the steel pipe into the required pipe end bell and spigot steel pipe through special equipment.
3) And the outer part of the bell and spigot steel pipe is derusted, oxide skin during bell and spigot processing can be removed, and the adhesive force of epoxy powder or cold spray paint is increased, so that the depth of anchor lines, the dust degree and the cleanliness on the surface of the steel pipe meet the specified requirements.
4) And (3) performing intermediate frequency heating on the powder, wherein the steel pipe is heated to the powder melting temperature of about 210 ℃ before powder spraying so that the epoxy powder can be melted and coated on the pipe wall of the steel pipe.
5) Powder spraying, namely uniformly spraying epoxy powder on the surface of the steel pipe by using a spray gun by utilizing the principle of electrostatic spraying, and adjusting the pressure of the spray gun to ensure that the thickness of an epoxy powder coating reaches the specified requirement.
6) And winding the adhesive layer and PE, simultaneously winding the adhesive and PE polyethylene on the steel pipe in the epoxy powder gelling process after spraying the epoxy powder, and adjusting the coating thickness by adjusting the extrusion capacity of the extruder so that the thickness of each layer meets the specified requirement.
7) And (4) cooling by water spraying, wherein the coated steel pipe enters a water spraying chamber, and the water spraying is carried out for a period of time, so that the temperature of the surface of the final outer anti-corrosion pipe reaches the specified requirement and is suitable for detection.
Preferably, the steel pipe socket must be subjected to heat preservation operation during the machining process, and the machining temperature must be maintained at 400 ° or higher.
Preferably, when the end of the steel pipe is heated, the heating temperature is 850-950 ℃, and the heating length is 300-400 mm.
Preferably, 10-20 spray guns are used according to the pipe diameter in the powder spraying of the steel pipe, and the powder output of a single gun is about 500 g/min.
(III) advantageous effects
Compared with the prior art, the invention provides a production process of a wound 3PE bell and spigot steel pipe, which has the following beneficial effects:
the production process of the wound 3PE bell and spigot steel pipe can greatly improve the corrosion resistance of a pipeline and the flexibility of field construction by developing a production process and a product which combine the advantages of the connection of 3PE and a bell and spigot, and the performance index of the wound 3PE bell and spigot steel pipe can completely reach the corrosion resistance effect of 3PE by a mature bell and spigot steel pipe corrosion resistance production technology.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
A production process of a wound 3PE bell and spigot steel pipe comprises the following steps: the socket steel pipe socket intermediate frequency heating, heat the steel pipe end, the heating temperature is 850-950 degrees, the heating length is 300-, uniformly spraying epoxy powder on the surface of a steel pipe by using a spray gun, adjusting the pressure of the spray gun to ensure that the thickness of an epoxy powder coating reaches the specified requirement, using 10-20 spray guns according to different pipe diameters in powder spraying, wherein the powder output of a single gun is about 500g/min, a glue layer is wound and PE is wound, after the epoxy powder is sprayed, an adhesive and PE polyethylene are simultaneously wound on the steel pipe in the epoxy powder gelling process, the coating thickness is adjusted by adjusting the extrusion amount of an extruder, so that the thickness of each layer reaches the specified requirement, cooling by water spraying, allowing the coated steel pipe to enter a water spraying chamber, and spraying water for a period of time to ensure that the final surface temperature of the outer anti-corrosion pipe reaches the specified requirement and is suitable for detection;
the socket 3PE steel pipe is internally anticorrosive, including internal rust removal and external rust removal, the powder spraying and the 3PE powder intermediate frequency heating spraying are carried out, but high-temperature epoxy powder is required to be adopted at the position to prevent the coated epoxy powder from melting when the external 3PE corrosion prevention is carried out and reheating is carried out, a two-component mixing pump is adopted for cold spraying, the coating is conveyed to a nozzle, the proper pipe rotating speed, spraying air pressure and advancing speed of a coating trolley are adjusted to enable the wet film thickness and the appearance of the inner wall of the steel pipe to meet the specified requirements, the cold spraying is different from the epoxy powder corrosion prevention, the steel pipe does not need to be heated in advance, the steel pipe after the cold spraying corrosion prevention needs to be heated and solidified, a heating furnace is heated to about 60-80 ℃, the temperature is kept for 20-;
except for bell and spigot and internal and external corrosion prevention technologies, the bell and spigot 3PE technology also needs other auxiliary processes and technologies, such as polishing of a 3PE layer at the end part, removal of the 3PE layer at the groove port, epoxy powder supplement, manufacturing of a bell and spigot drag hook, steel pipe identification and protection and the like.
Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (4)
1. A production process of a wound 3PE faucet steel pipe is characterized by comprising the following steps:
1) the bell and spigot steel pipe is subjected to medium-frequency heating, so that the metal fluidity and plasticity of the pipe end are improved, and the structure of steel is optimized.
2) And (4) bell and spigot processing, namely processing the steel pipe into the required pipe end bell and spigot steel pipe through special equipment.
3) And the outer part of the bell and spigot steel pipe is derusted, oxide skin during bell and spigot processing can be removed, and the adhesive force of epoxy powder or cold spray paint is increased, so that the depth of anchor lines, the dust degree and the cleanliness on the surface of the steel pipe meet the specified requirements.
4) And (3) performing intermediate frequency heating on the powder, wherein the steel pipe is heated to the powder melting temperature of about 210 ℃ before powder spraying so that the epoxy powder can be melted and coated on the pipe wall of the steel pipe.
5) Powder spraying, namely uniformly spraying epoxy powder on the surface of the steel pipe by using a spray gun by utilizing the principle of electrostatic spraying, and adjusting the pressure of the spray gun to ensure that the thickness of an epoxy powder coating reaches the specified requirement.
6) And winding the adhesive layer and PE, simultaneously winding the adhesive and PE polyethylene on the steel pipe in the epoxy powder gelling process after spraying the epoxy powder, and adjusting the coating thickness by adjusting the extrusion capacity of the extruder so that the thickness of each layer meets the specified requirement.
7) And (4) cooling by water spraying, wherein the coated steel pipe enters a water spraying chamber, and the water spraying is carried out for a period of time, so that the temperature of the surface of the final outer anti-corrosion pipe reaches the specified requirement and is suitable for detection.
2. The process for producing a wound 3PE bell and spigot steel pipe as claimed in claim 1, wherein the steel pipe bell and spigot must be kept warm during the processing, and the processing temperature must be kept above 400 ℃.
3. The production process of the wound 3PE bell and spigot steel pipe as claimed in claim 1, wherein the heating temperature is 850-950 ℃ and the heating length is 300-400mm when the pipe end of the steel pipe is heated.
4. The process for producing a wound 3PE bell and spigot steel pipe as claimed in claim 1, wherein 10-20 spray guns are used for powder spraying of the steel pipe according to the pipe diameter, and the powder output of each spray gun is about 500 g/min.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010942774.1A CN111998142A (en) | 2020-09-09 | 2020-09-09 | Production process of wound 3PE faucet steel pipe |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010942774.1A CN111998142A (en) | 2020-09-09 | 2020-09-09 | Production process of wound 3PE faucet steel pipe |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111998142A true CN111998142A (en) | 2020-11-27 |
Family
ID=73469724
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010942774.1A Pending CN111998142A (en) | 2020-09-09 | 2020-09-09 | Production process of wound 3PE faucet steel pipe |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111998142A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114682465A (en) * | 2022-02-25 | 2022-07-01 | 山东东宏管业股份有限公司 | Anticorrosion method for three-layer polyethylene inside and outside epoxy resin inside bell and spigot steel pipe |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105221850A (en) * | 2015-09-30 | 2016-01-06 | 张翼飞 | A kind of anticorrosive steel rib strengthens Spiral Steel Pipe and preparation method thereof |
| CN105710157A (en) * | 2016-04-01 | 2016-06-29 | 天津市科建防腐保温工程有限公司 | Steel-plastic composite anti-corrosive steel pipe with bell-and-spigot joint function |
| CN106076790A (en) * | 2016-08-31 | 2016-11-09 | 渤海石油装备福建钢管有限公司 | More than DN1400mm large-diameter steel pipe inside and outside wall Anticorrosion measure |
| JPWO2015083811A1 (en) * | 2013-12-06 | 2017-03-16 | 古河電気工業株式会社 | Corrosion prevention method for welded part of plastic lining steel pipe and presser adhesive tape for heat shrinkable anticorrosion sheet |
| CN208090157U (en) * | 2018-03-23 | 2018-11-13 | 云南固特邦钢塑管道制造有限公司 | A kind of high-frequency heated spigot-and-socket flaring plastic-coated steel |
| CN109253346A (en) * | 2018-10-17 | 2019-01-22 | 山东禹王管业有限公司 | A kind of bell and spigot anti-corrosive steel tube |
| CN110486573A (en) * | 2019-08-23 | 2019-11-22 | 重庆金智燃管件有限公司 | Steel special piece surface anticorrosion structure and its construction method |
-
2020
- 2020-09-09 CN CN202010942774.1A patent/CN111998142A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPWO2015083811A1 (en) * | 2013-12-06 | 2017-03-16 | 古河電気工業株式会社 | Corrosion prevention method for welded part of plastic lining steel pipe and presser adhesive tape for heat shrinkable anticorrosion sheet |
| CN105221850A (en) * | 2015-09-30 | 2016-01-06 | 张翼飞 | A kind of anticorrosive steel rib strengthens Spiral Steel Pipe and preparation method thereof |
| CN105710157A (en) * | 2016-04-01 | 2016-06-29 | 天津市科建防腐保温工程有限公司 | Steel-plastic composite anti-corrosive steel pipe with bell-and-spigot joint function |
| CN106076790A (en) * | 2016-08-31 | 2016-11-09 | 渤海石油装备福建钢管有限公司 | More than DN1400mm large-diameter steel pipe inside and outside wall Anticorrosion measure |
| CN208090157U (en) * | 2018-03-23 | 2018-11-13 | 云南固特邦钢塑管道制造有限公司 | A kind of high-frequency heated spigot-and-socket flaring plastic-coated steel |
| CN109253346A (en) * | 2018-10-17 | 2019-01-22 | 山东禹王管业有限公司 | A kind of bell and spigot anti-corrosive steel tube |
| CN110486573A (en) * | 2019-08-23 | 2019-11-22 | 重庆金智燃管件有限公司 | Steel special piece surface anticorrosion structure and its construction method |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114682465A (en) * | 2022-02-25 | 2022-07-01 | 山东东宏管业股份有限公司 | Anticorrosion method for three-layer polyethylene inside and outside epoxy resin inside bell and spigot steel pipe |
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| PB01 | Publication | ||
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| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20201127 |
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