The pipeline industry's default armour
Every modern long-distance pipeline you can name — from ARAMCO trunklines, to PDO export lines, to GAIL's national gas grid — uses some flavour of three-layer polyethylene coating. The 3LPE system stacks three engineered layers in sequence, each doing one job exceptionally well, and the combination outlives every single-layer alternative on the market.
We run two parallel 3LPE production lines at our facility, both equipped with induction pre-heat and side-extrusion polyethylene wrapping, capable of pipes from 1/2 inch right up to 60 inch diameter.
Three layers, three jobs
Layer 1 — Fusion-bonded epoxy primer. A heat-cured epoxy powder, electrostatically deposited onto blast-cleaned steel at 220-240 °C. The primer chemically bonds to the steel and forms the actual corrosion barrier — without it, the rest of the system wouldn't matter.
Layer 2 — Copolymer adhesive. A maleic-anhydride-grafted polyethylene that grafts onto both the still-molten FBE below and the polyethylene topcoat above. This is the layer that prevents 3LPE from ever delaminating in service.
Layer 3 — Polyethylene topcoat. Either MDPE or HDPE, side-extruded at 1.5-3.5 mm thickness, providing the mechanical, UV and water-vapour barrier.
Specifications we deliver
| Parameter | Range |
|---|---|
| Pipe diameter | 1/2" to 60" (15-1500 mm) |
| Total coating DFT | 1.8 to 4.2 mm |
| Service temperature | -40 °C to +80 °C continuous |
| Holiday detection | 25 kV factory test, 100% of pipe surface |
| Adhesion @ 23 °C | ≥ 100 N/cm |
| Cathodic disbondment | < 7 mm at 28 days |
Where we deploy 3LPE
- Onshore crude and gas trunklines across the GCC and India, including sour-service lines.
- Subsea and offshore flowlines, often in combination with concrete weight coatings.
- Buried potable water mains where DIN 30670 and AWWA compliance is required.
- Industrial slurry and brine pipelines that need both internal lining and 3LPE outside.
- Long-haul district heating networks in mountain or rocky terrain where mechanical loading is high.
Standards we work to
We coat 3LPE to multiple international standards depending on the project specification:
- DIN 30670 — German national standard, the original 3LPE specification
- ISO 21809-1 — international, buried and subsea
- CSA Z245.21 — Canadian, common on North-American export projects
- NFA 49-710 — French infrastructure
- Project-specific specs for Saudi ARAMCO (APCS), ADNOC, PDO Oman, GAIL, ONGC and HPCL are all routinely supported
Our quality control loop
Every length of pipe is inspected at five points before it leaves the plant:
- Mill test certificate cross-check at receipt
- Surface profile measurement after blast cleaning (target Sa 2½, 50-100 µm anchor)
- Temperature uniformity check during pre-heat (IR pyrometer)
- Coating thickness measurement at 4 points per metre, both circumferentially and axially
- Holiday detection at 25 kV across the full length, with automatic flagging of any defect
Coating coupons are retained from every batch for cathodic disbondment testing and adhesion peel tests at 28 days.
Common questions our buyers ask
How is 3LPE different from FBE alone? FBE delivers the corrosion barrier; 3LPE adds the adhesive and PE layers for impact, abrasion and handling protection. For a pipeline going into rocky soil, deep water, or directional drilling — choose 3LPE. For a pipe rack inside a refinery — FBE alone is enough.
What's the temperature ceiling? 80 °C continuous service. Above that, switch to 3LPP (polypropylene topcoat), which we also produce on a separate line for sustained 110 °C duty.
What about field-applied joint coatings? Welded girth joints are protected with our heat-shrinkable sleeves (HSS) or liquid-epoxy field kits — both fully compatible with the mainline 3LPE system.
