PUR Cable – The Ultimate FAQ Guide

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PUR, short for polyurethane, is a material that has been used in cables since the 60s.

It offers a unique set of benefits that suit the multitudes of applications.

This post aims to provide a detailed FAQ guide of PUR cables.

PUR cables are known for their tough physical properties.

You’ll find them in areas with tough conditions.

This sheathing material is often compared with PVC, which is different from it in many ways.

When buying any kind of cable with PUR as its sheathing, understanding the properties of the material will help you make the right choice.

Even if the material is inherently sturdy, qualities can vary.

What is PUR cable?

Any cables that use PUR or Polyurethane (also abbreviated as PU sometimes) are essentially PUR cables.

PUR is a thermoplastic polymer, which means it has high heat-resistance and can be recycled.

Its properties are comparable with a thermosetting rubber, which isn’t recyclable.

Polyurethane also comes as thermosetting polymers.

This material is used in myriads of products, from the sponge in your kitchen to the gasket in your car.

It’s also part of synthetic fibers, adhesives, tires, foam, and hard-plastics.

In cabling, it’s used for sheathing.

It’s not really ideal for insulation, so when we talk about PUR cables, we’re talking about cables with PUR outer sheath.

PUR cables come in many different forms, sizes, and constructions.

Many international standards dictate the material as the outer sheath material as per the application of the cable.

So PUR cable is a very broad term, but it helps understand the characteristics and qualities of the cable, as those qualities are common across the different kinds of cables.

PUR cables are generally high-performance cables, so most cables that require tough sheathing use PUR.

What is the Characteristic of PUR Cable?

Polyurethane or PUR is a versatile material with many characteristics that help make it so vital for outer sheath on cables.

If we’re talking categories of PUR characteristics, they can be divided into two categories:

Mechanical Features

The mechanical features are super important when it comes to the sheath.

Insulation, as such, doesn’t get mechanical pressure.

To properly gauge the mechanical strength of a cable, one has to evaluate the sheath material.

Here are the mechanical features of the PUR cables:

• Tear Resistance: PUR has high tensile strength, which essentially makes it tear-resistant. Itis also highly wear-resistant, which means it doesn’t age quickly. As a result, the PUR outer sheath makes it hard for the cable to break, either through mechanical stress or environmental factors.
• Abrasion Resistance: Consider this an extension of its tear-resistance, as PUR is also good at withstanding abrasion. Abrasion in cabling is a common problem, which is why most outer sheath materials are abrasion-resistant. If the cable is bending over a sharp corner, it won’t wear or break.
• Bending Resistance: PUR is flexible enough to coil and bend, which is why it’s ideal for retractable cables too. However, it strikes the right balance between high and low bending resistance. It’s flexible enough to bend around the corners without breaking, but it’s also stiffer than some of the other cables that have a high bending radius.
• Impact Resistance: For industrial use, PUR cables also provide impact-resistance. This depends on the type and quality of PUR as well, but, generally, these cables offer ample protection from direct impact.
• Flame Resistance: While PUR is not fire-resistant, it’s considered flame-resistant or flame-retardant. These cables are not immune to damage from fire; however, they don’t propagate flames. This property makes these cables safe to some extent in case of a fire. As for the operating temperature, that normally ranges from -40 to 125 Celcius.

Chemical Features

These cables also provide chemical protection, which makes them ideal for use in industries that may be susceptible to chemicals or other agents coming in contact with the wires.

• Oil Resistance: PUR is resistant to most mineral oils. In comparison with rubber and even PVC, PUR provides better resistance against oils. Oils can react with the materials and damage the cable, but PUR doesn’t let that happen.
• Water Resistance: PUR is water-resistant, but it’s important to understand what that means. While it may not be damaged when in contact with water, it’s not completely waterproof. This means prolonged exposure to water can result in a reaction and subsequent damage. Nevertheless, PUR cables that are specifically designed for offshore or outdoor use provide ample resistance to keep working even during wet conditions.
• Ozone Resistance: Ether Polyurethane, which is a type of polyurethane, is also ozone-resistant. It prevents ozone from causing degradation of the sheath itself and the insulation.
• UV Resistance: Direct sunlight does not damage PUR cables. However, discoloration is still possible, but that doesn’t indicate any impact on insulation or core.
• Antimicrobial: PUR doesn’t let microbial damage the integrity of the cable. However, that applies to PUR with a polyether base. Those with a polyester base may still be susceptible to microbial growth in damp conditions.

What is the Application of PUR Cable?

As PUR is notable for its strong, protective characteristics, it’s used in a wide variety of industries, especially where the conditions may be rough.

In terms of types of cable applications, PUR cables are used as energy cables, control cables, sensor cables, automation cables, drag cables, and equipment wiring.

So these cables cover a wide range of industries:

• Power generation
• Nuclear power
• Mining
• Food Industry
• Automation/Robotics
• Electronics
• Medical industry
• Airports and railway stations
• Transport systems
• Automotive industry
• Steel and iron production
• Chemical industry
• Water treatment plants
• Offshore sites

So you can see that these cables are used in many industries.

Of course, the exact kind of cables differs by application.

However, the common denominator in all these cables is the PUR sheath.

Different properties of PUR make it ideal for different applications.

For instance, these cables don’t attract microbes and bacteria, which makes it ideal for the food industry.

They have to follow strict hygiene standards, which extends all the way to cabling as well.

Similarly, the water-resistance makes it good for off-shore use, and chemical-resistance makes it ideal for industrial use where chemicals are used.

It also has a fairly high-temperature range, which allows it to operate in industries that typically have very high ambient temperatures (steel production, mining, water treatment, etc.)

What are the Benefits of PUR Cable?

It’s clear that PUR has a lot of benefits to offer based on its characteristics, which is why it’s such a popular choice in cable sheathing.

Goto FSW to know more.

• Tough Material: The first line of defense in any cable is its outer sheath. It has to be tough, especially if the conditions the cables are in are rough, such as high temperatures, oils, or water. PUR is a sturdy material with very high wear-resistance. In other words, it won’t tear, and it would be difficult to cut too.
• Environmental Protection: Cables are mostly in danger of environmental damage. Wind, rain, fire, and sunlight can damage a cable. So that’s upon the sheath to protect the insulation and core from these elements. And PUR is a good material for this purpose. It can withstand oils, chemicals, water, and UV rays. This makes it good for offshore and outdoor use as well, as generally, these environmental threats exist in outdoor settings.
• Halogen-Free: PUR cables are mostly halogen-free, which makes them a safe option. Many industries and governments mandate the use of halogen-free cables, which means no component of the cable can have a halogen in its composition. This is because when these elements burn, they produce very toxic gases that further worsen the situation in case of a fire.
• Reliability: It just comes down to the reliability of the cables for most consumers, and PUR is a reliable material. It provides more than adequate protection, which is its main job as a sheathing material. Regardless of the cable type or standard, PUR offers many protective qualities that ensure the cables stand the test of time.
• Flame-Resistant: PUR is flame-resistant or flame-retardant, which is a safety feature. These cables won’t start a fire or propagate it. But they may not be able to keep the integrity of the insulation or core very long in a fire. Polyurethanes generally have a lower melting point than some of the other thermoplastics.

What is the difference between PUR cable & PVC cable?

Polyvinyl Chloride or PVC is another important material used in insulation and sheathing in cables.

It’s similar to PUR in some ways and very distinct in others.

So you may have to deliberate which one is best for your specific application.

One apparent difference between PUR and PVC is that PVC is often used for insulation as well, in addition to the outer sheath in low-voltage cables.

PUR is not suitable for insulation, so it’s only found as a sheathing material.

PVC cables provide excellent chemical resistance but are not that great for oil resistance.

They can withstand exposure and washdown to a variety of chemicals used in the food industry.

However, they are not as resistant to mineral oils and emulsifiers as PUR, which makes PUR more suitable for applications like tool-making and automotive industries.

In terms of mechanical stress, PUR is sturdier than PVC.

That said, PVC does provide adequate abrasion resistance and impact resistance.

PV cables can also operate at high temperatures easily, but they get rigid and inflexible at very low temperatures.

On the other hand, PUR cables remain flexible, even below zero degrees.

PVC cables with an IP69 rating are waterproof.

Generally, all PVC cables are water-resistant to some extent, much like PUR.

With PVC, the characteristics depend on a number of factors, such as temperature, duration of exposure, frequency of exposure, the intensity of impact, etc.

It varies greatly by quality, size, and type, so not all PVC cables are the same.

It’s also important to note that PVC contains chlorine, which is a halogen.

PUR cables are halogen-free, which is a major advantage over PVC, as halogens can be dangerous in a fire.

In some industries, PVC cables may be forbidden for use because of this property.

What is the Standard of PUR Cable?

Standards in cables are provided by a handful of international and regional bodies that govern the rules for safety and consumption.

These standards basically ensure you’re using the best cable solution for the application in question.

These standards are indicated by numbers and have proper definitions that define the materials, their nature, and their purpose.

When it comes to PUR cables, there are no definitive standards defining PUR sheath.

However, PUR cables come under standards that maintain a thermosetting plastic sheath.

PUR cables that are fire-retardant may come under fire-resistant standards as well.

Those for offshore use come under the marine cable standards.

Similarly, these cables also meet the standardization of low-smoke halogen-free (LSHF) cables.

The most common standards in cables include:

• International Electrotechnical Commission (IEC)
• British Standards Institute (BS)
• European Standards (EN)
• Japanese Industrial Standards (JIS)

There are regional and local bodies as well, with variations of the standards provided by the above bodies.

Depending on your industry and country, you may have to follow those standards.

Conclusion

PUR is a robust and sturdy material used for sheathing in cables.

Any kind of cable that uses a polyurethane outer sheathing is essentially a PUR cable.

Offering high tensile strength, flame-resistance, water-resistance, and chemical-resistance, these cables are some of the toughest in the market.

PUR cables have a wide range of applications, spawning from food production to the industrial assembly line, and even robotics.

While the characteristics may vary slightly by the type of polyurethane in the cable, this material is generally great for use in tough environments, especially outdoors.

Cutting and cooling oils are used in component production in industry for temperature control and tool conservation. This means that cables, connectors or cable glands used to connect the actuators and sensors in the system are permanently or temporarily exposed to various oils.

Oil-resistant LAPP products are resistant to lubricating, cutting and cooling oils, chemical cleaning agents and hot water, making them ideally suited to many industrial applications in production or production.

For example, our oil-resistant SKINTOP® cable glands offer long-term resistance to various oils. This means that your cable gland remains functional even after an extended period of use in oil, does not ripple or fall.

For special applications, e.g. in a CNC processing centre, cables also have to be permanently laid in oil or resistant to hot cooling lubricant. An oil-resistant outer sheath of the cable ensures a functioning connection with low risk of failure in the long term.

The company is the world’s best pur cable material supplier. We are your one-stop shop for all needs. Our staff are highly-specialized and will help you find the product you need.