The Importance of Choosing the Right Oil-Resistant Cable Protection

Oil is one of the most damaging chemicals to which electrical wires can be exposed.  It cannot be stopped once oil damage to the cable insulation or jacketing starts. Eventually, this leads to cable failure, costly downtime, and even more costly replacements.

Due to regulatory changes in renewable energy, auto manufacturing, aerospace technology, and mechanical production—there is a renewed focus on cable protection designed to manage the challenges of oil exposure. Of course, depending on the application, environment, and materials the range of protection varies.

Let’s look at the impact of oil on cables, how to diagnose oil exposure issues, and how to select the best oil-resistant cable protection based on your specific requirements.

How Applications and Environment Impact Oil Degradation

Oil can serve as both a coolant and lubricant in industrial and infrastructure applications. 

For example, as a lubricant, oil can be applied to hydraulic systems to protect pumps, cylinders, and other components from premature failure. As a coolant, it may be applied to air-cooled aviation engines to minimize extra heat when taxiing or under other extraneous conditions.

Even if not directly exposed, cables positioned underneath or around oil applications have an increased risk of indirect prolonged exposure. In all of these situations oil works in concert with environmental factors like extreme temperature and oxygen level shifts, furthering the possibility of cable damage. 

We mention this because the oil application and specific conditions of exposure will influence the oil-resistant properties required in your cabling. Not all wire and cable insulations are created equal. 

Higher degrees of flame resistance or flexibility often lead to diminished or complete absence of other traits. Environmental, electrical, and chemical configurations will vary and you’ll need to account for these attributes to avoid selecting the wrong configuration of compounds.

Diagnosing Oil Exposure Problems

As we mentioned, once oil starts to damage the polymers used in cable jacketing and insulation, there’s no stopping it. The damaged state can provide insight into the type of oil resistance you need to invest in. 

Ideally, you research and select cables with inherent oil resistance before this occurs—but if you experience unforeseen downtime, and believe it’s due to cable failure, here are the visual problems to look out for.

Swelling and Cracking

Results from cable materials being exposed to oil and the plasticizers either absorbing or being completely removed in the process. 

Depending on the materials and properties of the oil and other chemicals, the insulation will increase in diameter, pushing the cable against surrounding components, or it will harden and crack—exposing the internal wiring. 

Melting

Weakened insulation may no longer prevent electrical current from flowing through the cable, leading to increased resistance and heat generation. In combination with high external temperatures, this will cause the cable to overheat and eventually melt.

Discoloration

Often occurring in combination with one of the above issues, discoloration is caused by colorant from the insulation diffusing into the plasticizers alongside the oil. This can be an early sign of exposure and may not lead to immediate problems, but it does signal the need for a replacement.

Choosing the Right Oil-Resistant Cable Protection

When selecting oil-resistant cable sleeving or tubing the goal is to maximize longevity when exposed to the specific oil composition, environment, and other chemicals in your operations. While that involves a variety of factors, you can look at just four things to identify a viable option.

1. Determine the Level of Exposure

Even if there’s a small chance of incremental exposure, you don’t want to leave your cables unprotected. You just may not need the highest level of resistance if occasional contact with oil occurs versus constant immersion. 

Knowing how often your cables will be exposed can help narrow down your options significantly.

2. Understand Industry-Specific Requirements

The automotive, energy, electrical, and aerospace industries all have unique cable performance requirements and needs. Depending on the application, greater flexibility, flame retardant, or abrasion resistance may be required. 

While that doesn’t eliminate oil resistance it will require some tradeoffs. It may mean you end up with cable protection that won’t be quite as durable, but you’ll at least check all the boxes.

3. Know your material options

The effectiveness of oil-resistant cables and sheathing ultimately depends on the materials used. Different compounds have unique reactions to oil exposure, with some being far more resistant than others.

PVC tends to be the most common material. It’s flexible and affordable but requires additional treatment to avoid oil absorption. It’s really only best used in situations where no prolonged exposure is expected. 

Alternatives like polyurethane (PU) or thermoplastic elastomers (TPE), which also include thermoplastic polyurethane (TPE-U) offer a far higher-level of oil-resistance. These are typically best for more extreme conditions and prolonged exposure. 

4. Review Regulatory Standards

Without a deep understanding of the polymer composition of your cables, it can be difficult to know how effectively it will resist oil degradation. 

However, by knowing the level of expected exposure and additional requirements for your cables—you can turn to UL (oil resistance) standards to see how the cable will react in a given environment. 

These tests involve continuous immersion at elevated temperatures over a specified period. Cables pass if the level of tensile strength and elongation meet or exceed the minimum requirement.  

While there are additional standards and optional testing available, these are the most common:

Oil Res I Rating

Standard industry rating representative of average exposure conditions. Cables that pass are likely to handle intermittent contact with oil but will see substantial degradation with ongoing submersion.

• Length of Immersion: 4 Days 
• Temperature: 60°C
• Standard: 50% retention of unaged tensile and elongation

Oil Res II Rating

Advanced industry rating representative of prolonged exposure conditions at more extreme conditions. Cables that pass are likely able to handle being submerged or experience extended contact with oil for a far longer period.

• Length of Immersion: 60 Days 
• Temperature: 75°C
• Standard: 65% retention of unaged tensile and elongation

Depending on your industry, you may be required to use cables at a minimum standard with the option to use a higher standard if applicable. Depending on the product, the cable will pass one or more of these qualifications as well as flame and flexibility standards. 

Count on the Experts at Titan Electronics

There’s a lot to consider when comparing oil-resistant cable protection. But, understanding the impact and complications of oil degradation and following the steps outlined above, will point you in the right direction.

Need additional support? No matter the application you need oil resistance for, you can count on the experts at Titan Electronics to guide you to the best product for your specific requirements. 

Explore our cable management solutions for manufacturing, aerospace,  and electrical applications. For hands-on support, reach out to our product specialists today at (866)956-8323 or complete our contact form and we’ll reach out to you.

About The Author

Joe Wigginton is a seasoned Sales Manager with a rich background in the aerospace and defense industries. With over 20 years of experience in the cable and cable protection sector, Joe initially served as a manufacturers' representative for 5 years before taking the entrepreneurial route. For the past 15 years, he has successfully owned and operated a business dedicated to supporting customers with top-quality products and solutions.

Beyond his professional achievements, Joe has traveled extensively worldwide to forge meaningful relationships and source the best products to meet our customers' needs. His global perspective and commitment to excellence make him a valuable asset to our team and clients alike.