Skip links

Circulating Oil System: What You Should Know?

Circulating oil system is a cost-effective solution as it gives optimum longevity to large, heavy and high-speed bearings. It is primarily designed for cooling and proper filtration of the lubricating oil circulated across the system.

There are predesigned circulating oil systems available in the market. One can also get it custom made depending upon the requirements. It can be adapted as per the operational capacity.

Circulating oil system adds continuous flow of lubricant to all the critical components such as bearings, blowers, gearboxes and more. It is used for a wide range of purposes such as extracting oil, circulate air into mines, pump stormwater, power water transportation and ships.

It is also widely used in the manufacturing sector mainly in paper and chemicals, and also to test military equipment. Although the bearing manufacturer normally supplies the oil and lubes.

They also educate around the level of lubrication required for the system. But in most cases where overheating and wear & tear is common, circulating oil system is recommended. This is because it works as a more dynamic lube system.

More about the approach, function and system requirements:

There are mainly three commonly adopted approaches used in the industry.

circulating oil system

The First approach is to arrange in-house resources. So you don’t have to depend upon third parties and other resources to organize everything smoothly. There are experts who take care of everything for you and deliver an effective in-house system. They would do all the job right from connection to assembling the pipes and ensure the whole system works seamlessly.

The second approach is to buy a pre-built system. The Good news is that there are manufacturers who have ready to use system that can be used instantly. It means there is less time invested in the process and it can be put to use right away. It ensures a short lead time which is extremely helpful while dealing with a bearing that is constantly overheating during summertime. The key here is to find the right manufacturer because the options are limited. Not paying attention may result in under equipped or misalignment. Sometimes the efficiency is not optimal too so you are better off finding good suppliers.

The Last approach is to get the system designed and organized by a good manufacturer who has proven expertise. Good vendors will take care of everything such as engineering, drafting and fitting. They also have sub manufactures and suppliers who are trustworthy. They handle all the maintenance and troubleshooting jobs. Since circulating oil system is meant for decades of service, it is always advisable to design it with optimum controls, easy maintenance and considerable efficiency.

How do you determine system requirements?

Every application plays a critical role. It is good to consult a bearing manufacturer to understand the exact flow rate, type of fluid, temperature and pressure to ensure there is a robust system in place.

Ensure system requirements are well defined. Check the line distance, elevation, surrounding temperature, availability of power, and safety measures.

You can also add modifications electronically to provide readings and feedback to the operator. It gives warnings and alerts to the system operator and hence action can be taken proactively.

Bearings should operate smoothly and that requires a circulating oil system to perform well.

What are the main requirements for a circulating oil system?

Some of the key factors that you need to carefully consider to achieve an effective circulating oil system are as follows:

Pressure – Standard operating pressure is usually around 30 to 35 psi. But you may require a customized application for better systems. Make sure you can adjust the pressure and obtain higher output if needed.

Flow Rate- It is important to have a good flow rate in place. Align the flow rate to what bearing needs. This would result in a controlled flow rate throughout.

Filtration – There are mainly three layers of filtration required.

First, a baffle is fitted in the reservoir to separate the sides. This lets the residue shift to one side and the oil flows to the other.

When the fluid goes out of the reservoir there is a mesh strainer that further filters it.

Final filtration takes place right before the oil exiting the system with the help of a 23-micron filter.

Make sure all these crucial components are cleaned and the filter is replaced at regular intervals.


Pumps and Motors There are motors in place with different voltage output and frequencies to derive optimal power results. The motor is fan called and enclosed.

Gauges – Gauges lets you constantly monitor the operating performance. These pressure gauges are very useful in verifying that the pump is functioning properly or not.

Heat Exchangers – The main use of a heat exchanger is to bring down the oil temperature before passing it to the bearing. Heat exchangers are crucial as they transfer heat from the fluid to air or water.

Immersion Heaters – Its main function is to ensure the system starts without any hiccups during cold temperatures. When it’s freezing outside, the system may need this to function efficiently and without any problems.

Environment – Before designing the system, things like temperature, humidity, and other important conditions must be taken into consideration.

Reservoirs and Piping – Piping and reservoirs can be stainless steel or welded steel. The connectors are welded and fittings are flanged for a good connection. It is advisable to thoroughly inspect and test the circulating oil systems before making them operational.

Designing perfect circulating oil systems depends upon the conditions. Experts advise assessing all the factors and then align the systems. Working closely with the bearing manufacturer is key here. There are different systems for different requirements. Hence adjust accordingly and get the right components and measures in place for an effective and high performing system.

Leave a comment