Paraffinic Vs Naphthenic Transformer Oil: Which Is Better?

You may be wondering, which paraffinic vs naphthenic transformer oil-which is better? Well, the answer is not so easy because depending on the oil your application will run perfectly.

There is much more historical information and knowledge on naphthenic than paraffinic in transformers. Naphthenic oils are traditionally considered the gold standard.

Paraffinic oil is gaining traction because it is virtually sulfur-free. But naphthenic base oils are not completely sulfur free. However, to know more details information about paraffinic and naphthenic oils please read on.

Difference Between Paraffinic vs Naphthenic Transformer Oil:

The key difference between paraffinic and naphthenic is that paraffinic refers to materials containing paraffin compounds. In contrast, naphthenic refers to materials containing naphthene.

Also, the general formula of paraffinic compounds is CnH2n+2 whereas the naphthenic compound is CnH2n. Furthermore, when converting crude oil to gasoline, converting naphthenic crude oil to gasoline is relatively easy. It’s the opposite of paraffinic crude oil. Let’s go to know what is Naphthenic and paraffinic oil.

What Is Paraffinic Oil?

Paraffinic transformer oil also comes from crude oil but contains more wax than the naphthenic type. Increased wax content also expands the pour point of the liquid, which means it may need to be lowered with additives.

When an application calls for operating a transformer in freezing temperatures, water can normally form as ice melts. In addition, if that water flows into the electrode transformer area the dielectric/liquid oil strength will reduce. A low breakdown voltage value is a sign of oil moisture or other conductive materials.

At cold temperatures, paraffinic oil contains lower density than naphthenic oil. Relatedly, there is a big difference in density between paraffinic oil and floating ice. So, people often choose this oil for low-temperature applications.

What Is Naphthenic Oil?

Naphthenic meaning is derived from naphthene, referring to cyclohexane. Also, Naphthenic transformer oils come from crude oil with little or no naturally occurring waxes. Accordingly, naphthenic oil contains a low pour point.

A fluid pour point is a temperature below which it loses its ability to flow freely when tipped from a container. Hence, naphthenic transformer oil has a lower wax than other oils.

It exhibits a lower pour point without needing people to use additives to artificially lower it. Nevertheless, regarding longevity, technicians should check the oil at least annually.

Sludge is a common problem with some transformer oils. Nonetheless, the naphthenic liquid contains moderately soluble sludge. Additionally, this feature means that it won’t build up deposits on the windings.

But it will negatively affect the cooling capacity of the transformer. Moreover, this facility prevents temperature rise problems in the transformer which can shorten the life of the equipment.

Naphthenic Vs Paraffinic Base Oil

Naphthenic oils are distinguished by a molecular structure composed of “rings” of hydrocarbons. That is, hydrogen and carbon atoms are linked in a circular pattern. Besides this, naphthenic oils don’t contain wax and behave differently than paraffinic oils.

Adequately, paraffinic base oils are prepared from paraffinic crude oils by the solvent separation technique. Yet, it also gives good yields from high-viscosity index stocks containing large amounts of wax.

Paraffinic has excellent oxidative and thermal stability and high-temperature viscosity properties. Likewise, Naphthenic base oils derived from naphthenic crude are very readily available and very cheap. They yield medium and low viscosity index base oils with low pour points.

Paraffinic And Naphthenic Oil Price:

Due to the abundance of high-production bases, naphthenic base oil competes extremely with Group II and III base oil.

The market is influenced by shifting crude oil prices and a change in demand for heavy and sour crude. And naphthenic oil is sold at a lower price than sweet crude. On the other hand, paraffinic base oil price is more expensive than naphthenic oil.

Naphthenic Oil Vs Mineral Oil:

Naphthenic crude oil is a type of crude oil that contains high amounts of naphthenic compounds. Subsequently, naphthalene is a cyclic, aliphatic hydrocarbon produced from petroleum oil.

The structure of hydrocarbon molecular rings distinguishes naphthenic oils from other mineral oils. Naphthenic oils don’t have paraffin wax. The quality of anthemic oils includes low viscosity, good stability, high volatility, and a low pour point.

They are generally used for applications with narrow temperature ranges where a low pour point is needed. Mineral oil, another name is liquid petroleum, is a byproduct of the gasoline production process. Mainly, this product is transparent and composed mainly of hydrocarbon alkanes.

Undoubtedly, humans can use this mineral oil safely. Approved by the Food and Drug Administration for individual care, as a food additive and cosmetic item. Even mild baby oil products are manufactured from mineral oil.

Naphthenic Transformer Oil

Paraffinic Oil vs Naphthenic oil: Which Is Better?

Naphtha oil can be more easily oxidized than paraffin oil. But the products of oxidation in naphtha oil sludge are more soluble than in paraffin oil sludge. Therefore, naphtha-based oil sludge does not accumulate at the bottom of the transformer. So it does not obstruct the conduction of the oil, meaning it doesn’t disturb the transformer cooling system.”

One of the main problems with paraffin-based oils is that the waxes dissolved inside can have a high pour point. Although this is not a problem in warm climate conditions. Paraffin-based oils are used in many countries because of their high availability.

FAQ (Frequently Asked Questions):

Q. What is naphthenic oil used for?

In various sectors, Naphthenic base oils are widely used including industrial, automotive, and tire manufacturing. During the projection period, in the automotive sector government investment increased.

Particularly in developing economies like South Africa, Mexico, and India, will increase the demand for naphthenic base oils.

Q. What is the difference between paraffinic and naphthenic oil?

Paraffinic oil contains a high viscosity index though it’s good for motor oil but bad for transformers. In contrast, naphthenic oil has lower viscosity meaning in transmission there will be more oil circulation and excellent cooling.

Q. What are paraffinic oils and naphthenic oils?

Accordingly, Paraffinic oil is a type of crude oil it contains high amounts of paraffin. On the contrary, naphthenic crude oil is a type of crude oil that contains a high amount of naphthenic compounds.

Q. Is paraffin and naphtha the same?

No, it’s because there are key differences. The key differences are paraffinic substances have alkanes and naphthenic substances have cyclic aliphatic hydrocarbons. That’s why they won’t be the same as well.

Final Word:

In summary, Paraffin oil contains a lower oxidation rate than naphtha oil. Ultimately, the sludge acts as a barrier in the transformer cooling system.

The difference between paraffinic and naphthenic transformer oil mainly depends on the main hydrocarbon type of the oil. For example, paraffinic oils primarily contain higher alkanes, whereas naphthenic contains a higher proportion of cyclic alkanes in the blend.

However, we hope you get the proper information about paraffinic oil vs naphthenic oil from this article. It’s because we are trying to give exact information about this topic.

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I am Engr. Z Eusuf Lubricant Specialist, Mechanical Engineer & has been working with engine lubricants for a long time and knows what makes them work best. I can help you find the right oil for your needs, and I have tips on how to keep your engine running at its best.