Free cookie consent management tool by TermsFeed

Next day delivery


Great customer service


Trade account available


Market Leader in Everything Hydraulic

Which Oil Can Be Used Within Hydraulic Systems?

Which Oil Can Be Used Within Hydraulic Systems?

To ensure the smooth running of any hydraulic system the correct hydraulic oil needs to be present. This is a non-compressible fluid that is used to transfer power within hydraulic machinery and equipment to guarantee the smooth running of the whole system.

Seems simple and straight forward? But there are many kinds of hydraulic oils available.

Hydraulic oils fall into two categories:
• Mineral Based – this is derived from crude oil,
• Synthetic – this is a man-made formula.

These can then be split into further types of hydraulic oils:
Mineral Oils
As read above, mineral oils are created from the refining process of crude oil and then altered to improve the quality by adding certain substances. HH – this is a not inhibited oil.
o HL – this has had additives added to make the oil anti-corrosive and anti-dust.
o HM – additives have also been added to this one like HL but have had another type of additive added to make it have anti-wear properties.

Fire Resistant Fluids
There are several common types of fire-resistant hydraulic fluids
HFAE – this is an oil in a water emulsion.
o HFAB – this consists of 40% water in an oil emulsion.
o HRAS – a chemical solution in water.
o HFC – this is a water polymer solution containing water glycol.
o HFDR – this synthetic fluid is made from phosphate ester.
o HFDS – this is a synthetic oil made of chlorinated hydrocarbons.

Water/Oil Emulsions
Within these types of hydraulic oils, the predominant substance (on average 60%) is oil, where chemicals have been added to enable the water to mix with the oil substance.

Water Glycol
The HFRC hydraulic oil is a mixture of 40% water with 60% glycol. One advantage of this solution is that it works at a lower temperature than emulsion solutions.

Phosphate Esters
This HFDR hydraulic oil is fire-resistant and does not ignite unless the oil reaches a temperature above 550◦c. A disadvantage of this hydraulic oil is that it can be chemically active which leads it to strip paint and destroy rubber, leading to a slightly higher expense due to repair work.

Every hydraulic system has a preferred type of oil, as without these oils the system would cease and be unable to perform its tasks. That’s why you should make sure you know what hydraulic oil to use and you should check the oil levels regularly.

Flowfit offer a range of hydraulic oils in varying sizes and types, so never get low on oil, ensure to order yours today!

We are always here to help, whilst hydraulic systems come with a guide to their best suited hydraulic oil it can be confusing. Don’t get confused, contact out team today by calling 01584 879 033 or e-mail us at and we’ll be sure to find you the right oil for your hydraulic system

Enjoyed this article? Share on social!
VK WhatsApp Telegram

The total one-stop supplier for hydraulic components & systems

Get in touch

find us

find us

Parys Road

call us

Request a product

Request a product or part

* Required Fields
Back To Top