Viscoelastic Inner Tape
ISO 21809-3 /13A Compliant | 100 mm × 10 m × 1.8 mm | Primary Corrosion Protection for 3LPE Repair
Product Overview
Our Viscoelastic Inner Tape is a high-performance, non-crystalline, low-viscosity polyolefin-based mastic tape engineered as the primary corrosion protection layer in the repair of 3LPE-coated pipelines. Formulated from a non-polar polymer mastic, this tape provides direct adhesion to both bare steel surfaces and existing PE coatings—without the need for a primer—forming a continuous, watertight barrier that restores the integrity of the pipeline coating system.
Supplied in a convenient 100 mm × 10 m × 1.8 mm roll, this tape is qualified to ISO 21809-3 /13A and suitable for operating temperatures up to +80°C.
Product Specifications
| Parameter |
Specification |
| Product Type |
Viscoelastic inner tape (polyolefin-based mastic) |
| Material Structure |
Non-crystalline, low-viscosity, non-polar polymer mastic |
| Dimensions |
100 mm (Width) × 10 m (Length) × 1.8 mm (Thickness) |
| Standard |
ISO 21809-3 /13A |
| Operating Temperature |
Up to +80°C |
| Application |
Primary corrosion protection layer in 3LPE repair |
Key Features & Benefits
| Feature |
Benefit |
| Non-Crystalline, Low-Viscosity Mastic |
Cold-flows into surface irregularities, pits, and weld seams for complete coverage |
| Non-Polar Polyolefin Base |
Chemically compatible with PE coatings; provides direct adhesion without primer |
| Direct Adhesion to Steel and PE |
Eliminates the need for a separate primer; simplifies application and reduces field time |
| Primary Corrosion Protection Layer |
Forms the innermost barrier against moisture, oxygen, and corrosive soils in 3LPE repair systems |
| ISO 21809-3 /13A Qualified |
Meets the international standard for viscoelastic field joint coatings at the specified temperature rating |
| High Operating Temperature (+80°C) |
Suitable for pipelines operating at elevated temperatures within the standard 3LPE service range |
| Self-Healing Behavior |
Minor damages close automatically under compression, maintaining continuous protection |
System Integration
The Viscoelastic Inner Tape is designed as the first protective layer in a 3LPE repair system. Typical system configuration:
| Layer |
Product |
Function |
| 1 (innermost) |
Viscoelastic Inner Tape (this product) |
Direct adhesion to steel and PE; primary corrosion barrier |
| 2 |
Viscoelastic Outer Tape or compatible overwrap |
Mechanical protection; additional moisture barrier |
| 3 (optional) |
Outerwrap / Topcoat |
UV protection for exposed environments |
The tape is applied directly to the prepared steel surface and overlapping onto the existing PE coating, creating a continuous bond across the repair zone.
Typical Properties (Reference)
| Property |
Typical Value |
| Thickness |
1.8 mm |
| Width |
100 mm,150 mm ,200mm |
| Length |
10 m per roll |
| Operating Temperature |
75 ,95°C |
| Standard Classification |
ISO 21809-3 /13A |
| Adhesion |
Direct to steel and PE (primer-free) |
| Color |
Black or as specified |
| Shelf Life |
24 months (unopened, cool dry storage) |
Values are indicative and shall be confirmed against the specific CNPetro product data sheet.
Compliance with ISO 21809-3 /13A
ISO 21809-3 specifies requirements for field joint coatings on buried and submerged pipelines. The /13A classification designates a viscoelastic tape system qualified for the specified operating temperature range. This product is tested and certified to meet the performance requirements of this classification, including adhesion, cathodic disbondment resistance, and thermal ageing at the rated temperature.
Primary Applications
-
3LPE pipeline repair – Restoration of damaged or degraded coating at field joints and repair areas
-
Pipeline rehabilitation – Corrosion protection where direct adhesion to steel and PE is required
-
Field joint coating – Primary inner layer in viscoelastic repair systems
-
Buried and submerged pipelines – Onshore and offshore environments
-
Operating temperatures up to +95°C – Suitable for standard and elevated-temperature 3LPE service
Application Summary
Surface Preparation: Clean the steel surface and adjacent PE coating to remove loose rust, dirt, oil, and contaminants. Surface should be dry and frost-free.
Apply Tape: Starting at one end, apply the tape spirally around the repair area with the specified overlap, pressing firmly to ensure intimate contact with both steel and PE.
Overwrap (if specified): Apply the outer tape or overwrap over the inner tape for mechanical protection.
Inspect: Verify complete coverage, sealed edges, and proper overlap. No curing time is required before backfill.
Packaging and Availability
| Item |
Details |
| Roll Dimensions |
100 mm × 10 m × 1.8 mm |
| Packaging |
Individually wrapped rolls in cartons |
| Customization |
Other widths and lengths available on request |
CNPetro — Protecting pipelines. Advancing performance.
For product data sheets, ISO 21809-3 /13A qualification certificates, or technical consultation, please contact our sales team.
Keywords: viscoelastic inner tape, polyolefin mastic tape, 3LPE repair, ISO 21809-3 /13A, primer-free corrosion protection, 100 mm × 10 m × 1.8 mm, pipeline coating repair, PE-compatible tape
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