Coating process for pipeline three-layer structural anticorrosive coating

A technology of three-layer structure and coating process, which is applied in the direction of pipeline anticorrosion/rust protection, pipeline protection, and devices for coating liquid on the surface, etc. It can solve the problem of inability to establish surface microcohesion and surface fusion, and the influence of FBE and steel pipe bonding , unable to form surface meshing and other problems, to achieve the effect of low preparation cost, reduced material cost, and improved cathodic disbondment resistance

Inactive Publication Date: 2011-06-29
BC P INC CHINA NAT PETROLEUM CORP +1
View PDF4 Cites 22 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0017] Before the FBE powder is completely melted, it has a high roughness, but when the FBE is completely melted and leveled, this state disappears, and at this time AD is entangled, and the two cannot form surface engagement; if the FBE is not fully gelled For pre-winding AD, it is possible that under the action of AD winding force, the combination of FBE and steel pipe will be affected
This restriction makes it impossible for the two to establish effective surface microcohesion and surface fusion.
[0018] The above problems affect the adhesion of the anti-corrosion coating, especially the high-temperature cathodic stripping performance (maximum operating temperature, 30d cathodic stripping, stripping value ≤ 15mm) stipulated in the national standard GB / T buried steel pipeline polyethylene anti-corrosion coating technical standard is not easy achieve

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Coating process for pipeline three-layer structural anticorrosive coating
  • Coating process for pipeline three-layer structural anticorrosive coating
  • Coating process for pipeline three-layer structural anticorrosive coating

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0046] A coating process for pipeline three-layer structure anti-corrosion coating, comprising the following steps:

[0047] 1) FBE coating, the curved steel pipe is heated, and epoxy powder is sprayed onto the surface of the curved steel pipe by electrostatic spraying process, so that the epoxy powder coating is melted and solidified into a primer;

[0048] 2) AD coating, during the epoxy powder gelling process, apply the adhesive powder to the surface of the curved steel pipe in step 1), the surface temperature of the curved steel pipe is 170°C, and the coating thickness is 100 μm;

[0049] 3) Polyolefin coating, before the adhesive cools down, wrap the polyolefin PE tape fixing frame heated to 160°C on the curved steel pipe described in step 2) in a lateral winding method, and the tape overlaps by 55% , Heat the surface of the pipe and the PE tape during winding to fuse the PE tape, and the coating thickness is 0.5mm.

Embodiment 2

[0051] A coating process for pipeline three-layer structure anti-corrosion coating, comprising the following steps:

[0052] 1) FBE coating, the steel pipe is heated, and the epoxy powder is sprayed on the surface of the steel pipe by electrostatic spraying process, so that the epoxy powder coating is melted and solidified to form a primer;

[0053] 2) AD coating, before the epoxy powder is gelled, apply the adhesive powder to the surface of the steel pipe in step 1), the surface temperature of the steel pipe is 225°C, and the coating thickness is 350 μm;

[0054] 3) Polyolefin coating, before the adhesive cools down, the polyolefin PP strip heated to 220°C is wound onto the steel pipe described in step 2) through a rotary winding machine, and the strip overlaps by 55%. The surface of the pipe and the PE tape are heated to fuse the PE tape, and the coating thickness is 4.0mm.

Embodiment 3

[0056] A coating process for pipeline three-layer structure anti-corrosion coating, comprising the following steps:

[0057] 1) FBE coating, the substrate to be coated is heated, and epoxy powder is sprayed onto the surface of the substrate to be coated by electrostatic spraying process, so that the epoxy powder coating is melted and solidified into a primer;

[0058] 2) AD coating, before the epoxy powder is gelled, apply the adhesive powder to the surface of the coated substrate in step 1), the surface temperature of the coated substrate is 200°C, and the coating thickness is 200 μm;

[0059] 3) Polyolefin coating, before the adhesive cools down, the AD / PE composite tape of the polyolefin inner layer composite adhesive heated to 200 ° C is wound onto the coated substrate described in step 2) through a rotary winding machine. On the material, the strip overlaps by 55%. When winding, the pipe surface and the PE strip are heated to fuse the PE strip. The coating thickness is 2....

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
thicknessaaaaaaaaaa
Login to view more

Abstract

The invention discloses a coating process for a pipeline three-layer structural anticorrosive coating. The coating process comprises the following steps of: 1) performing fusion bonded epoxy (FBE) coating, namely heating a coated substrate, and spraying epoxy powder to the surface of the coated substrate by an electrostatic spraying process to melt an epoxy powder coating and cure the epoxy powder coating into a bottom coating; 2) performing air dielectric (AD) coating, namely coating adhesive powder to the surface of the coated substrate during gelling of the epoxy powder, wherein the surface temperature of the coated substrate is between 170 and 225 DEG C, and the coating thickness is between 80 and 350 mu m; and 3) performing polyolefin coating, namely winding a fabricated polyolefin coil strip on the coated substrate before an adhesive is cooled, wherein the coating thickness is between 0.5 and 4.0mm. By the AD powder coating process, the wound coating is tightly adhered to the substrate, and the anticorrosive coating has high integrity, cathodic disbonding resistance and compactness.

Description

technical field [0001] The invention relates to the field of pipeline anticorrosion, in particular to a process for coating a pipeline with a three-layer structure anticorrosion layer. Background technique [0002] The "three-layer structure" anti-corrosion layer of the steel pipe includes three layers of polyethylene (English abbreviation: 3PE or 3LPE) and three-layer polypropylene (English abbreviation: 3PP or 3LPP), which is currently recognized as the most advanced pipeline anti-corrosion layer. It has a wide range of applications and reliable anti-corrosion performance. [0003] The three-layer structure specifically refers to the bottom layer as fusion bonded epoxy powder coating (English abbreviation as FBE), and the middle layer as synthetic adhesive (including α-olefin and ethylene copolymer adhesive, graft polymerization modified polyethylene adhesive two types, English Abbreviated as: AD), the outer layer is polyolefin (including polyethylene, English abbreviated...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): B05D1/38B05D1/02B05D7/02F16L58/10F16L58/16
Inventor 廖宇平穆铎刘毅王留斌张自力
Owner BC P INC CHINA NAT PETROLEUM CORP
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap