Three-Layer Polypropylene (3LPP) Coated Line Pipe

Three-Layer Polypropylene (3LPP) Coated Line Pipe
Coating diameter: NPS 2" - 56" (60.3-1422.4mm) Coating standards: DIN 30678, ISO 21809-1, NFA 49-711.
-Laminated polypropylene (3LPP) coated line pipe

USI STEEL can produce 3LPP 3-layer polypropylene coating for API 5L PSL 1 & PSL 2 line pipe, from NPS 2" to NPS 56" (60.3mm - 1422.4mm), if you have such inquiry, welcome to contact us.

Three-layer polypropylene (3LPP) coating The 3LPP coating system is a multi-layer coating composed of three functional components: high-performance fused epoxy (FBE), copolymer binder and medium density polypropylene (MDPP) or an outer layer of high-density polypropylene (HDPP) to protect against external corrosion.

Specifications and standards for 3LPP coatings are DIN 30678, ISO 21809-1, NFA 49-711, SHELL DEP 31.40.30.31-CSPC



DIN 30678-2013 Polypropylene coatings on steel pipes and fittings

ISO 21809-1:2011 Oil and gas industry - External coatings of buried or underwater pipelines used in pipeline transportation systems - Part 1: Polyolefin coatings (3 layers PE and 3 layers PP)

NFA 49-711 exterior coating with three layers of polypropylene applied by extrusion

SHELL DEP 31.40.30.31-CSPC Line pipe exterior polyethylene and polypropylene coating



Fused Bonded Epoxy (FBE): The first layer of FBE should be 150 microns thick.

Adhesive: Second layer of extruded copolymer adhesive, 200 microns thick.

Polypropylene (MDPP/HDPP): Third layer of extruded polypropylene (MDPP/HDPP), thickness 1.6 – 2.95 mm.



Coating application:

Pipe surface preparation by sand blast cleaning (SSPC-SP10/NACE No.2/ISO 8501-1 Sa 2 1/2/SIS 05 59 00)

After the pipe is heated and melted, it should be coated with epoxy powder

The extruded adhesive should be applied to the pipe.

Finally, a layer of extruded polypropylene (MDPP or HDPP) should be applied over the adhesive layer.

Total coating thickness is typically < 3.0 mm for pipes < 24" diameter and 3.3 mm for pipes 32" diameter and larger)