Cable for Cathodic Protection: Halar vs Kynar

The cathodic protection industry is a rugged one, and cables used in CP applications need to be able to withstand extreme soil, water and gaseous environments: brackish water, corrosive liquids, harsh underground conditions.

CP Cables can have several layers of coating on them.  In addition to the HMWPE layer (which can be used alone for CPC), one of the most important layers is fluoropolymer insulation, which is often thencovered with an HMWPE jacket.  Our cables use two different types of fluoropolymers: ECTFE and PVDF.

ECTFE

Stands for: polyethylenechlorotrifluoroethylene (say what?)
aka: Halar (Solvay Solexis brand)
Description: Semi-crystalline melt-processable copolymer of ethylene and chlorotrifluoroethylene.
Attributes:

• Excellent abrasion resistance
• Mechanical properties over a wide range of temperatures
• Chemical resistance to a variety of acids, bases and organic solvents
• Rated for continuous use from cryogenic temperatures up to 150°C and higher
• Good electrical properties
• Fire and Smoke performance
• Excellent weatherability
• Thermal stress-cracking resistance
   

PVDF

Stands for: polyvinylidene fluoride (that one’s a little easier)
aka: Kynar (Arkema brand),Hylar and Solef (both Solvay Solexis brands)
Description: Semi-crystalline melt-processable vinylidene fluoride based homopolymers and copolymers
Attributes:

• Excellent fatigue, creep and cut-through resistance
• Readily cross-linkable with ionizing radiation after compounding with co-agents
• Chemical resistance to a variety of acids, bases and organic solvents
• Low melting point of 177°C (easier melt process)
• Fire and Smoke performance
• Good electrical properties
• Excellent weatherability
• Low density
• Low cost
   

We cover both of our products with HMWPE, and suggest Halar as the fluoropolymer of choice.  Both of these insulation types significantly increase the level of durability of the CPC, making them much more reliable once installed in a cathodic protection system.