The type of insulation utilized in wire and cable determines the overall quality and the range in application. Then there are also the high demands placed on materials by different environments. International standard mentions several different types of insulating materials such as thermosetting and thermoplastic materials as our focus. What could possibly be the beneficial aspects of the thermoplastic insulated cables which many consumers refer as the “green cables”? Let’s find out.
What is thermoplastic insulated cable?
Thermoplastic insulated cable is a type of cable that utilizes a thermoplastic material seamlessly extruded around the core of the cable or wire as its insulating layer. The cable is characterized by the ability of the insulation to soften or melt when heated and re-harden when cooled, a process that can be repeated many times. Thermoplastics are shape-stable plastics at ambient temperatures that flow consistently and therefore deform plastically in a reversible manner over a higher temperature range. The Thermoplastic cable temperature range is material dependent and therefore a unique characteristic of materials. Moreover, cables can be repaired or recycled relatively easily when damaged or when the insulation needs to be replaced.
What are the pros and cons of thermoplastic material?
Thermoplastic Insulation Advantages:
- Easy to process, fast molding.
- Diversified processing methods, including extrusion, injection molding, casting, blow molding, etc., can efficiently prepare a variety of complex products.
- Recyclable, environmentally friendly and economical.
- Good electrical properties, suitable dielectric constant.
- Strong impact resistance, good toughness.
- Wide range of operating temperatures, adaptable.
- Low cost, easy maintenance.
Thermoplastic Insulation Disadvantages:
- Limited high temperature stability.
- Relatively low mechanical strength.
- Less durable than thermoset materials in harsh environments.
What is thermoplastic insulation used for?
Thermoplastic insulation is used in a wide range of industrial and wire and cable applications, including household wiring, data transmission cables, automotive wire harnesses, and internal connecting cables for a variety of electronic devices. They are very common in residential, commercial, and light industrial environments because these cables provide reliable electrical insulation while offering great flexibility and convenience during installation.
Thermoplastic sheathed cables also excel where frequent plugging and unplugging is required, where there are special flexibility requirements, or where environmental adaptability is important, such as in automobiles, appliances and outdoor temporary power installations. In aerospace, medical equipment and specialized cables for high-temperature environments, they provide the necessary insulation protection.
Thermoplastic insulated cable types
In terms of cable coverings and insulation, thermoplastic insulation comes in a variety of forms. Let’s examine some typical thermoplastic examples.
- PVC (Polyvinyl Chloride)
After decades of production and use, PVC manufacturing and processing technology is now well established. Compared to other types of cable insulation, PVC jacket cables is not only cost effective, but also excels in electrical insulation, flame retardancy and durability. It is mainly used in low voltage cables up to 1kV.
- PE (Polyethylene).
Polyethylene (PE) sheath material as cable sheath has excellent dielectric properties, low temperature resistance, stress cracking resistance. Generally, similar to PVC insulation PE thermoplastic cables are also rated at +70°C. It is widely used in transmission lines and underground cable systems.
- Teflon (Polytetrafluoroethylene or PTFE).
Teflon cables, or more commonly high temperature cables, employ fluoroplastic insulation such as FEP, PFA, and PTFE. It is suitable for working in the temperature range of -200 ℃ to 260 ℃ and therefore finds application in a number of high temperature industries. It has high corrosion resistance, oil resistance, strong acids, strong bases, strong oxidizers resistance, and anti-microbial inhibiting fungus formation.
- Silicone rubber
Silicone wire has very good high and low temperature resistance, it can work in an environment ranging from -60℃ to 200 ℃. It has a long operating life and is mostly used in metallurgy, electric power, petrochemical, electronics, automobile manufacturing and other industries.
- Elastomer and thermoplastic elastomer (TPE) cables
Elastomer and thermoplastic elastomer cables combine the flexibility of rubber with the processing advantages of plastic for a wide range of applications. From medical devices to children’s toys and fitness equipment. In particular, thermoplastic elastomers TPE cables offer the high elasticity, aging and oil resistance of traditional cross-linked vulcanized rubber.
Thermoplastic vs. thermoset: Which wire insulation is better?
| Aspect | Thermoplastic Insulation | Thermoset Insulation |
|
Hardness and Rebound |
Varies, generally softer 30% rebound rate |
Typically harder and more rigid 10% rebound rate |
| Temperature Resistance | Lower temperature resistance, can melt | High temperature resistance, stable |
| Chemical Resistance | Excellent chemical and corrosion resistance | Good resistance |
| Environmental Suitability | Suitable for a variety of environments | Ideal for extreme environments |
| Cost | Generally more cost-effective | Can be more expensive due to properties |
The above table graph clearly indicates that there exist notable variances of thermoplastic and thermoset insulation in as far as its characteristics and applications are concerned. Thermoplastics on the other hand have the ability to reverse and heat softening allowing the material to be processed and remolded more than once. It exhibits good flexibility and is adequate for electrical projects which need to be flexible, cost effective whilst durable. Whereas thermoset insulation is chemically cross-linked to form a permanent structure after initial heat curing. In other words, the product is formed over a period of time at a certain temperature, pressure or with the addition of a curing agent, and can no longer be recycled after curing. Their thermal endurance and rigidity are higher but more difficult to process. For example, XLPE thermosetting insulated cables are typically used for high voltage, motor windings and high temperature electronic equipment.
As the need for eco-friendly and safe cable materials increases, ZW Cable’s advanced production equipments and rugged products are available to meet the demand. If you have custom cable material or more power cable types, kindly reach our representative!
