3PE Anti-Corrosion Pipe
3PE (Three-Layer Polyethylene) anti-corrosion pipe features a composite coating system consisting of an epoxy primer layer (FBE), a copolymer adhesive middle layer, and a high-density polyethylene outer layer. This multi-layer system provides superior corrosion protection, mechanical damage resistance, and cathodic disbondment resistance compared to single-layer coatings, making it the industry standard for buried oil and gas pipelines worldwide.
Our 3PE coating line applies the coating under strictly controlled conditions with online holiday detection and thickness monitoring. The coating is tested per SY/T0413 and DIN 30670 for peel strength, impact resistance, indentation resistance, and long-term cathodic disbondment performance. Service temperatures range from -40\u00b0C to +80\u00b0C, suitable for most buried pipeline environments.
SY/T0413 / DIN 30670
Carbon Steel + 3PE
DN50-DN3000
Applications
- Buried oil and gas transmission pipelines
- Cross-country pipeline projects
- Offshore platform riser protection
- Underground water supply lines
- Chemical plant buried piping
Quality Assurance
All 3PE Anti-Corrosion Pipe products undergo NDT testing with MTC per EN 10204 3.1. Third-party inspection by SGS, BV, TUV available.
3PE Anti-Corrosion Coating System
3PE (three-layer polyethylene) coating is the industry-standard external anti-corrosion system for buried and submerged steel pipe. It combines excellent adhesion, mechanical protection, and cathodic disbondment resistance for 30-50 year service life.
| Layer | Material | Thickness | Function |
|---|---|---|---|
| Layer 1 | Fusion Bonded Epoxy (FBE) | 50-100 microns | Primary adhesion, cathodic disbondment protection |
| Layer 2 | Adhesive Copolymer | 170-250 microns | Bonds FBE to PE, shear strength transfer |
| Layer 3 | Polyethylene (PE) | 1.5-3.0mm | Mechanical protection, moisture barrier |
Total coating thickness ranges from 1.7mm (regular) to 3.7mm (reinforced) per DIN 30670 and SY/T 0413 standards.
Manufacturing Process & Standards
The 3PE coating process requires precise surface preparation and thermal application:
- Surface Preparation: Abrasive blasting to Sa 2.5 (near-white metal), surface roughness 50-75 microns, dust removal.
- Preheating: Pipe heated to 180-220C by induction heating for FBE curing.
- FBE Application: Epoxy powder sprayed onto hot pipe, gels and cures within seconds, forming the primary adhesion layer.
- Adhesive Extrusion: Copolymer adhesive side-extruded and wrapped around the pipe, bonding to FBE.
- PE Extrusion: Polyethylene outer layer extruded and wrapped, providing the mechanical and moisture barrier.
- Water Cooling: Quench to set the coating, then inspect.
- Holiday Test: Electrical inspection at 5kV/mm to detect any coating defects.
- Peel Test: Adhesion verification per DIN 30670 at 20C and 50C.
Standards: DIN 30670 (Germany), SY/T 0413 (China), CAN/CSA-Z245.21 (Canada), NACE RP0185. Service temperature range: -40C to +80C for standard 3PE.
Applications & Service Conditions
3PE coated pipe is the preferred system for long-life buried and submerged pipelines:
- Oil and Gas Transmission: Onshore buried pipelines for crude oil, natural gas, and refined products.
- Water Transmission: Municipal water supply and raw water lines, especially in corrosive soils.
- Subsea Pipelines: Offshore oil and gas lines requiring saltwater corrosion resistance.
- District Heating: Buried hot water and steam lines with PU foam insulation and 3PE outer jacket.
- Industrial: Chemical plant buried process lines, mine tailings lines.
3PE coating provides 30-50 year service life in buried applications, outperforming coal tar, tape wrap, and asphalt coatings. It resists cathodic disbondment, soil stress, and mechanical damage during handling and installation.