Cable for Cathodic Protection: Halar vs Kynar

Single Conductor, Dual Insulated CP Cables; Which is Better?

The cathodic protection (CP) 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 one layer of insulation, such as HMWPE, which is made for direct burial but does not have great chemical resistant properties. Therefore, there are cables with two laters of insulation known as "Halar" and "Kynar". In the case with Halar and Kynar, the primary or initial insulation or jacket is a chemically resistant fluoropolymer with long chemical names (see below). In addition to the primary cable insulation, the secondary layer or jacket is HMWPE, a flexible and tough cable jacket that resists abrasion. Combining the two layers then provides excellent abrasion and chemical resistance.

Which is better; Halar or Kynar? For CP purposes, there is really little difference. Halar has a longer list of chemicals that it is resistant to, so it has become defactor "standard" in CP industry. There is greater inventory of Halar and we find it in more specifications. Does that make Kynar less effective? No, but Halar is generally more available.

Cable Details:

ECTFE (Halar)
Stands for: Polyethylenechlorotrifluoroethylene
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 (Kynar)
Stands for: Polyvinylidene Fluoride
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
As indicated above, both cable products utilize an outer jacker of HMWPE. Just for availability along, we suggest Halar as the fluoropolymer of choice. Both of these insulation types significantly increase the level of durability of the cable, making them more durable once installed in a cathodic protection system.

The cathodic protection (CP) 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 one layer of insulation, such as HMWPE, which is made for direct burial but does not have great chemical resistant properties. Therefore, there are cables with two laters of insulation known as "Halar" and "Kynar". In the case with Halar and Kynar, the primary or initial insulation or jacket is a chemically resistant fluoropolymer with long chemical names (see below). In addition to the primary cable insulation, the secondary layer or jacket is HMWPE, a flexible and tough cable jacket that resists abrasion. Combining the two layers then provides excellent abrasion and chemical resistance.

Which is better; Halar or Kynar? For CP purposes, there is really little difference. Halar has a longer list of chemicals that it is resistant to, so it has become defactor "standard" in CP industry. There is greater inventory of Halar and we find it in more specifications. Does that make Kynar less effective? No, but Halar is generally more available.

Cable Details:

ECTFE (Halar)

Stands for: Polyethylenechlorotrifluoroethylene
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 (Kynar)

Stands for: Polyvinylidene Fluoride
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

As indicated above, both cable products utilize an outer jacker of HMWPE. Just for availability along, we suggest Halar as the fluoropolymer of choice. Both of these insulation types significantly increase the level of durability of the cable, making them more durable once installed in a cathodic protection system.