CN111662606A - Solvent-free internal anti-drag coating and construction method thereof - Google Patents
Solvent-free internal anti-drag coating and construction method thereof Download PDFInfo
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- CN111662606A CN111662606A CN201910161910.0A CN201910161910A CN111662606A CN 111662606 A CN111662606 A CN 111662606A CN 201910161910 A CN201910161910 A CN 201910161910A CN 111662606 A CN111662606 A CN 111662606A
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- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
- C09D163/00—Coating compositions based on epoxy resins; Coating compositions based on derivatives of epoxy resins
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- 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
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- 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
- B05D7/24—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 for applying particular liquids or other fluent materials
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- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
- C09D5/00—Coating compositions, e.g. paints, varnishes or lacquers, characterised by their physical nature or the effects produced; Filling pastes
- C09D5/08—Anti-corrosive paints
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- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Wood Science & Technology (AREA)
- Chemical & Material Sciences (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Paints Or Removers (AREA)
- Application Of Or Painting With Fluid Materials (AREA)
Abstract
The invention discloses a solvent-free internal resistance-reducing coating, in particular to a two-component curing cross-linking type epoxy coating, wherein the A component comprises the following raw materials in parts by weight: 50-60 parts of low-molecular epoxy resin, 3-5 parts of thixotropic agent, 3-5 parts of anti-settling agent, 3-5 parts of dispersing agent, 3-5 parts of flatting agent, 3-5 parts of defoaming agent, 10-15 parts of toughening resin, 5-7 parts of pigment, 5-7 parts of wear-resistant filler and 5-7 parts of antirust filler; the formula of the component B comprises the following raw materials in parts by weight: 22-24 parts of low-viscosity modified phenolic aldehyde amine curing agent. The invention also discloses a construction method of the solvent-free internal drag reduction coating.
Description
Technical Field
The invention relates to the technical field of preparation of internal resistance-reducing paint, in particular to solvent-free internal resistance-reducing paint and a construction method thereof.
Background
Although the existing internal anti-drag paint used for a natural gas long-distance pipeline has an anti-drag function, a large amount of volatile organic solvents (toluene, xylene and the like) seriously pollute the environment and harm the health of human bodies in the spraying process, so that a solvent-free internal anti-drag paint and a construction method thereof are provided.
Disclosure of Invention
The invention provides a solvent-free internal anti-drag coating and a construction method thereof, which aim to solve the problems in the background technology.
The invention provides a solvent-free internal resistance-reducing coating, in particular to a two-component curing cross-linking type epoxy coating, wherein the A component comprises the following raw materials in parts by weight: 50-60 parts of low-molecular epoxy resin, 3-5 parts of thixotropic agent, 3-5 parts of anti-settling agent, 3-5 parts of dispersing agent, 3-5 parts of flatting agent, 3-5 parts of defoaming agent, 10-15 parts of toughening resin, 5-7 parts of pigment, 5-7 parts of wear-resistant filler and 5-7 parts of antirust filler;
the formula of the component B comprises the following raw materials in parts by weight: 22-24 parts of low-viscosity modified phenolic aldehyde amine curing agent.
Preferably, the double-component curing crosslinking epoxy coating comprises the following component A raw materials in parts by weight: 55 parts of low-molecular epoxy resin, 4 parts of thixotropic agent, 4 parts of anti-settling agent, 4 parts of dispersing agent, 4 parts of flatting agent, 4 parts of defoaming agent, 13 parts of toughening resin, 6 parts of pigment, 6 parts of wear-resistant filler and 6 parts of antirust filler;
the formula of the component B comprises the following raw materials in parts by weight: 23 parts of low-viscosity modified phenolic aldehyde amine curing agent.
The invention also provides a construction method of the solvent-free internal drag reduction coating, which comprises the following steps:
s1, surface treatment, namely removing dirty matters such as oil welding slag, burrs, oil stains and the like on the surface of the base material, performing sand blasting to remove rust to reach Sa2.5 grade in GB/T8923.1, and then performing anchor line with the depth of 30-50 mu m;
s2, performing mechanical spraying prefabrication by adopting a bi-component high-pressure airless sprayer, heating the component A to 55-70 ℃ and the component B to 25-40 ℃ during spraying, pre-reflowing pipelines containing the component A and the component B before spraying, wherein the reflowing temperature of the pipelines is consistent with the actual temperature of the material A and the material B,
s3, fully and uniformly stirring the treated component A and the component B, and immediately constructing, wherein the dry film spraying thickness is 80-140 mu m, the dry film spraying thickness can be sprayed, and the spraying pressure during spraying is controlled within 0.3-0.5 MPa;
s4, detecting coating quality: when steel pipes are sprayed in a factory, experimental test pieces are stuck to the pipe ends, and then the pinholes, the thickness, the adhesive force, the bending and the medium soaking of the dry and wet film of the coating are checked according to standard regulations.
Preferably, the construction is stopped when the environmental humidity is greater than 85% or when the environment is rained.
Preferably, during winter construction, if the temperature is lower than-5 ℃, the temperature of the pipe body needs to be more than or equal to 10 ℃, the spraying line pipeline needs to be heated by a stirring device, the stirring temperature is 45-55 ℃, the sprayed steel pipe needs to enter a drying room for baking for 1-3 hours, and the baking temperature is 50-60 ℃, so that the curing is facilitated, and the performance of the coating is ensured.
Preferably, the materials are prepared according to the construction progress and the consumable condition, so that the gelled coating cannot be used any more after the materials are used up in 10 minutes.
The invention has the beneficial effects that: the solvent-free internal drag reduction coating realizes solvent-free, and solves the problems of solvent volatilization, environmental pollution and harm to human health. Through spray tests and laboratory tests, the performance of the solvent-free coating completely meets the requirements of API RP 5L2 and related domestic standards, the wear resistance, the adhesive force, the shearing strength, the luster, the resistance reduction performance and the corrosion medium immersion resistance performance of the solvent-based internal resistance reduction coating are far better than those of the solvent-based internal resistance reduction coating, the problems of low damage resistance, low chemical medium resistance, serious pollution and potential safety hazard of the solvent-based internal resistance reduction coating are effectively solved, the multiple properties of the internal resistance reduction coating can be further improved, the service life of the coating is prolonged, and the solvent-free internal resistance reduction coating is suitable for internal coating of long-distance and large-caliber natural gas transmission pipelines.
Detailed Description
The invention is further illustrated by the following examples.
Example 1
The invention provides a solvent-free internal resistance-reducing coating, in particular to a two-component curing cross-linking type epoxy coating, wherein the A component comprises the following raw materials in parts by weight: 50 parts of low-molecular epoxy resin, 3 parts of thixotropic agent, 3 parts of anti-settling agent, 3 parts of dispersing agent, 3 parts of flatting agent, 3 parts of defoaming agent, 10 parts of toughening resin, 5 parts of pigment, 5 parts of wear-resistant filler and 5 parts of antirust filler;
the formula of the component B comprises the following raw materials in parts by weight: 22 parts of low-viscosity modified phenolic aldehyde amine curing agent.
The invention also provides a construction method of the solvent-free internal drag reduction coating, which comprises the following steps:
s1, surface treatment, namely removing dirty matters such as oil welding slag, burrs, oil stains and the like on the surface of the base material, performing sand blasting to remove rust to reach Sa2.5 grade in GB/T8923.1, and then performing anchor line with the depth of 30-50 mu m;
s2, performing mechanical spraying prefabrication by adopting a double-component high-pressure airless sprayer, heating the component A to 55 ℃ and the component B to 25 ℃ during spraying, reflowing pipelines containing the component A and the component B in advance before spraying, wherein the reflowing temperature of the pipelines is consistent with the actual temperature of the material A and the material B,
s3, fully and uniformly stirring the treated component A and the component B, and immediately constructing, wherein the dry film spraying thickness is 80-140 mu m, the dry film spraying thickness can be sprayed, and the spraying pressure during spraying is controlled within 0.3-0.5 MPa;
s4, detecting coating quality: when steel pipes are sprayed in a factory, experimental test pieces are stuck to the pipe ends, and then the pinholes, the thickness, the adhesive force, the bending and the medium soaking of the dry and wet film of the coating are checked according to standard regulations.
When the construction is not dry, the construction is not drenched or wetted, and the construction is stopped when the environmental humidity is more than 85 percent or the construction is rained.
When in winter construction, if the temperature is lower than-5 ℃, the temperature of the pipe body needs to be more than or equal to 10 ℃, the pipeline of the spraying line needs to be heated by a stirring device, the stirring temperature is 45 ℃, the sprayed steel pipe needs to enter a drying room for drying for 1 hour, and the baking temperature is 50 ℃, so that the curing is facilitated, and the performance of the coating is ensured.
The materials are prepared according to the construction progress and the condition of consumables, so that the materials are used up in 10 minutes, and the gelled coating cannot be used any more.
Example 2
The invention provides a solvent-free internal resistance-reducing coating, in particular to a two-component curing cross-linking type epoxy coating, wherein the A component comprises the following raw materials in parts by weight: 55 parts of low-molecular epoxy resin, 4 parts of thixotropic agent, 4 parts of anti-settling agent, 4 parts of dispersing agent, 4 parts of flatting agent, 4 parts of defoaming agent, 13 parts of toughening resin, 6 parts of pigment, 6 parts of wear-resistant filler and 6 parts of antirust filler;
the formula of the component B comprises the following raw materials in parts by weight: 23 parts of low-viscosity modified phenolic aldehyde amine curing agent.
The invention also provides a construction method of the solvent-free internal drag reduction coating, which comprises the following steps:
s1, surface treatment, namely removing dirty matters such as oil welding slag, burrs, oil stains and the like on the surface of the base material, performing sand blasting to remove rust to reach Sa2.5 grade in GB/T8923.1, and then performing anchor line with the depth of 30-50 mu m;
s2, performing mechanical spraying prefabrication by adopting a bi-component high-pressure airless sprayer, heating the component A to 60 ℃ and the component B to 30 ℃ during spraying, reflowing pipelines containing the component A and the component B in advance before spraying, wherein the reflowing temperature of the pipelines is consistent with the actual temperature of the material A and the material B,
s3, fully and uniformly stirring the treated component A and the component B, and immediately constructing, wherein the dry film spraying thickness is 80-140 mu m, the dry film spraying thickness can be sprayed, and the spraying pressure during spraying is controlled within 0.3-0.5 MPa;
s4, detecting coating quality: when steel pipes are sprayed in a factory, experimental test pieces are stuck to the pipe ends, and then the pinholes, the thickness, the adhesive force, the bending and the medium soaking of the dry and wet film of the coating are checked according to standard regulations.
When the construction is not dry, the construction is not drenched or wetted, and the construction is stopped when the environmental humidity is more than 85 percent or the construction is rained.
When in winter construction, if the temperature is lower than-5 ℃, the temperature of the pipe body needs to be more than or equal to 10 ℃, the pipeline of the spraying line needs to be heated by a stirring device, the stirring temperature is 50 ℃, the sprayed steel pipe needs to enter a drying room for baking for 2 hours, and the baking temperature is 55 ℃, so that the curing is facilitated, and the performance of the coating is ensured.
The materials are prepared according to the construction progress and the condition of consumables, so that the materials are used up in 10 minutes, and the gelled coating cannot be used any more.
Example 3
The invention provides a solvent-free internal resistance-reducing coating, in particular to a two-component curing cross-linking type epoxy coating, wherein the A component comprises the following raw materials in parts by weight: 60 parts of low-molecular epoxy resin, 5 parts of thixotropic agent, 5 parts of anti-settling agent, 5 parts of dispersing agent, 5 parts of flatting agent, 5 parts of defoaming agent, 15 parts of toughening resin, 7 parts of pigment, 7 parts of wear-resistant filler and 7 parts of antirust filler;
the formula of the component B comprises the following raw materials in parts by weight: 24 parts of low-viscosity modified phenolic aldehyde amine curing agent.
The invention also provides a construction method of the solvent-free internal drag reduction coating, which comprises the following steps:
s1, surface treatment, namely removing dirty matters such as oil welding slag, burrs, oil stains and the like on the surface of the base material, performing sand blasting to remove rust to reach Sa2.5 grade in GB/T8923.1, and then performing anchor line with the depth of 30-50 mu m;
s2, performing mechanical spraying prefabrication by adopting a bi-component high-pressure airless sprayer, heating the component A to 70 ℃ and the component B to 40 ℃ during spraying, pre-reflowing pipelines containing the component A and the component B before spraying, wherein the reflowing temperature of the pipelines is consistent with the actual temperature of the material A and the material B,
s3, fully and uniformly stirring the treated component A and the component B, and immediately constructing, wherein the dry film spraying thickness is 80-140 mu m, the dry film spraying thickness can be sprayed, and the spraying pressure during spraying is controlled within 0.3-0.5 MPa;
s4, detecting coating quality: when steel pipes are sprayed in a factory, experimental test pieces are stuck to the pipe ends, and then the pinholes, the thickness, the adhesive force, the bending and the medium soaking of the dry and wet film of the coating are checked according to standard regulations.
When the construction is not dry, the construction is not drenched or wetted, and the construction is stopped when the environmental humidity is more than 85 percent or the construction is rained.
When in winter construction, if the temperature is lower than-5 ℃, the temperature of the pipe body needs to be more than or equal to 10 ℃, the pipeline of the spraying line needs to be heated by a stirring device, the stirring temperature is 55 ℃, the sprayed steel pipe needs to enter a drying room to be baked for 3 hours, and the baking temperature is 60 ℃, so that the curing is facilitated, and the performance of the coating is ensured.
The materials are prepared according to the construction progress and the condition of consumables, so that the materials are used up in 10 minutes, and the gelled coating cannot be used any more.
Example 4
Solvent-free internal drag reduction coating performance
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.
Claims (6)
1. A solvent-free internal drag reduction coating is characterized by being a two-component curing cross-linking type epoxy coating, wherein the A component comprises the following raw materials in parts by weight: 50-60 parts of low-molecular epoxy resin, 3-5 parts of thixotropic agent, 3-5 parts of anti-settling agent, 3-5 parts of dispersing agent, 3-5 parts of flatting agent, 3-5 parts of defoaming agent, 10-15 parts of toughening resin, 5-7 parts of pigment, 5-7 parts of wear-resistant filler and 5-7 parts of antirust filler;
the formula of the component B comprises the following raw materials in parts by weight: 22-24 parts of low-viscosity modified phenolic aldehyde amine curing agent.
2. The solvent-free internal drag reduction coating as claimed in claim 1, which is a two-component cured cross-linked epoxy coating, wherein the component A comprises the following raw materials by weight: 55 parts of low-molecular epoxy resin, 4 parts of thixotropic agent, 4 parts of anti-settling agent, 4 parts of dispersing agent, 4 parts of flatting agent, 4 parts of defoaming agent, 13 parts of toughening resin, 6 parts of pigment, 6 parts of wear-resistant filler and 6 parts of antirust filler;
the formula of the component B comprises the following raw materials in parts by weight: 23 parts of low-viscosity modified phenolic aldehyde amine curing agent.
3. A method of constructing a solventless internal drag reducing coating as claimed in claim 1 comprising the steps of:
s1, surface treatment, namely removing dirty matters such as oil welding slag, burrs, oil stains and the like on the surface of the base material, performing sand blasting to remove rust to reach Sa2.5 grade in GB/T8923.1, and then performing anchor line with the depth of 30-50 mu m;
s2, performing mechanical spraying prefabrication by adopting a bi-component high-pressure airless sprayer, heating the component A to 55-70 ℃ and the component B to 25-40 ℃ during spraying, pre-reflowing pipelines containing the component A and the component B before spraying, wherein the reflowing temperature of the pipelines is consistent with the actual temperature of the material A and the material B,
s3, fully and uniformly stirring the treated component A and the component B, and immediately constructing, wherein the dry film spraying thickness is 80-140 mu m, the dry film spraying thickness can be sprayed, and the spraying pressure during spraying is controlled within 0.3-0.5 MPa;
s4, detecting coating quality: when steel pipes are sprayed in a factory, experimental test pieces are stuck to the pipe ends, and then the pinholes, the thickness, the adhesive force, the bending and the medium soaking of the dry and wet film of the coating are checked according to standard regulations.
4. The method of claim 3, wherein the coating is not wet or wet when it is not dry, and is stopped when the humidity is greater than 85% or it rains.
5. The construction method of the solvent-free internal drag reduction coating as claimed in claim 3, wherein the temperature is lower than-5 ℃ in winter, the temperature of the pipe body is not less than 10 ℃, the pipeline of the spraying line is heated by a stirring device, the stirring temperature is 45-55 ℃, the sprayed steel pipe is baked in a baking room for 1-3 hours at 50-60 ℃ to facilitate curing and ensure the performance of the coating.
6. The construction method of the solvent-free internal drag reduction coating of claim 3, wherein the materials are prepared according to the construction schedule and the consumable condition, so as to ensure that the gelled coating cannot be used again after the materials are used up in 10 minutes.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910161910.0A CN111662606A (en) | 2019-03-05 | 2019-03-05 | Solvent-free internal anti-drag coating and construction method thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910161910.0A CN111662606A (en) | 2019-03-05 | 2019-03-05 | Solvent-free internal anti-drag coating and construction method thereof |
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| Publication Number | Publication Date |
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| CN111662606A true CN111662606A (en) | 2020-09-15 |
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| CN201910161910.0A Pending CN111662606A (en) | 2019-03-05 | 2019-03-05 | Solvent-free internal anti-drag coating and construction method thereof |
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Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3973510A (en) * | 1974-09-09 | 1976-08-10 | The United States Of America As Represented By The Secretary Of The Navy | Submersible object having drag reduction and method |
| CN102417780A (en) * | 2011-10-12 | 2012-04-18 | 上海海隆赛能新材料有限公司 | Anti-drag wear-resistant solvent-free coating with low-viscosity for pipeline |
-
2019
- 2019-03-05 CN CN201910161910.0A patent/CN111662606A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3973510A (en) * | 1974-09-09 | 1976-08-10 | The United States Of America As Represented By The Secretary Of The Navy | Submersible object having drag reduction and method |
| CN102417780A (en) * | 2011-10-12 | 2012-04-18 | 上海海隆赛能新材料有限公司 | Anti-drag wear-resistant solvent-free coating with low-viscosity for pipeline |
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