Understanding Self-Healing Cables: An Overview of Prysmian’s SUPERSEAL® Innovation

What are self-healing underground energy cables? 

Self-healing cables are underground power cables designed to automatically restore insulation after damage. In typical underground residential distribution (URD) systems, various factors such as shovels, dig-ins, abrasion, and punctures can compromise insulation. This damage can allow moisture to reach the conductor, leading to corrosion, increased leakage current, outages, and expensive repairs. 

Self-healing cables help prevent these issues by incorporating a built-in sealant that flows into any breaches in the insulation and blocks moisture from entering. The sealant moves in response to pressure changes caused by insulation compromise, and it stops flowing once the pressure stabilizes. This mechanism allows the cable to continue operating without any service interruptions. 

Prysmian Self-Healing Advanced Technology 

SUPERSEAL® is Prysmian’s advanced self-healing cable solution for low-voltage (600 V aluminum) direct-burial applications. It uses a proprietary EPDM-based sealant engineered for excellent dielectric performance, approximately 850–1000 V/mil, and a low dielectric constant for strong electrical insulation. Unlike other self-healing compounds, SUPERSEAL’s EPDM is thick, cohesive, and non-sticky, making it extremely clean and easy for utility crews to handle. It peels off without adhering to gloves, tools, or protective clothing. 

SUPERSEAL’s construction includes a layered extrusion system: an XLPE inner insulation layer, a rugged HDXLPE outer layer, and embedded sealant channels that ensure the sealant is always positioned to flow directly into any damaged area. This structure improves flexibility, reduces shrink back, and ensures consistent sealant distribution. 

In independent testing, including deliberate gouging with shovels and post-hole diggers, standard cables failed within weeks due to corrosion. At the same time, SUPERSEAL maintained near-zero leakage current and continued to operate normally. Mechanical tests also show that SUPERSEAL outperforms standard and ruggedized cables in abrasion, impact, crush, and puncture resistance. The cable requires no special tools or cleaners and uses standard stripping and termination techniques. It is available in single-, duplex-, triplex-, and quadruplex designs and meets UL 854, RUS requirements, and many ICEA S-81-570 mechanical abuse standards. Overall, SUPERSEAL is a direct, field-proven solution to URD failures caused by damage, providing a cleaner, more reliable, and more durable self-healing cable. 

Top 4 Reasons to Choose Prysmian® Self-Healing Technology: Solution for Low Voltage Underground Cables

1. Self-Healing Performance After Damage 

   Its EPDM-based sealant automatically fills gaps in insulation, restoring insulation integrity and keeping the cable in service even after severe digs, gouges, or punctures.

    

2. Proven Field Reliability 

   Third-party tests show that standard cables fail within weeks, while SUPERSEAL maintains near-zero leakage current and continues to operate normally. This provides strong confidence in long-term reliability.

    

3. Clean, Installer-Friendly Sealant 

   Unlike other self-healing designs, SUPERSEAL’s sealant doesn’t stick to gloves, tools, or clothing. It peels cleanly, reducing frustration and cleanup time during installation.

    

4. Dramatically Reduced Failure Rates

   SUPERSEAL prevents moisture ingress after mechanical damage, eliminating corrosion-related failures that commonly affect standard URD cables. Utilities avoid outages and improve service reliability. 

To learn more about SUPERSEAL, watch our product demo video.