3-Layer Polyethylene (3LPE) Coated Line Pipe

 

Three Layer Poly Ethylene (3LPE) coating 3LPE coating system is a multilayer coating composed of three functional components: a high-performance fusion-bonded epoxy (FBE), followed by a copolymer adhesive and an outer layer of Medium Density Polyethylene (MDPE) or High-Density Polyethylene (HDPE), which provides protection against external corrosion.

The codes and standards for 3LPE Coating are:

DIN 30670-2012, CAN/CSA Z245.21, ISO 21809-1, NFA 49-710, SHELL DEP 31.4030.31-CSPC

 

ISO 21809-1:2011 Petroleum and natural gas industries -- External coatings for buried or submerged pipelines used in pipeline transportation systems -- Part 1: Polyolefin coatings (3-layer PE and 3-layer PP)

CAN CSA Z245.21 External Polyethylene Coating for Pipe

 

NFA 49-710 External Three-Layer Polyethylene Based Coating, Application by Extrusion

 

SHELL DEP 31.40.30.31-CSPC External Polyethylene and Polypropylene Coating for Line Pipe

 

Fusion Bonded Epoxy (FBE): First layer of FBE shall be 150 microns thick.

Adhesive: Second layer of extruded co-polymer adhesive, 200 microns thick.

 

Polyethylene (MDPE/HDPE): Third layer of extruded polyethylene (MDPE/HDPE) or polypropylene (MDPP/HDPP), 1.6 – 2.95 mm thick.

 

Application of Coating:

Surface preparation of pipe by sandblast cleaning (SSPC-SP10/NACE No.2/ISO 8501-1 Sa 2 1/2/SIS 05 59 00)

Extruded adhesive shall be applied over the pipe.

Finally extruded polyethylene (MDPE or HDPE) layer shall be applied over the adhesive layer.