What Are Hydraulic Oil Coolers?

A hydraulic oil cooler is a heat exchanger designed to remove excess heat from the oil used to lubricate hydraulic system components. Without such a device, the oil would quickly overheat, causing mechanical damage and possibly even failure of the system. The removal of this extra heat allows the hydraulic oil to remain at an optimum working temperature, protecting the system and prolonging its service life.

The addition of an oil cooler to a hydraulic system can reduce the overall operating temperature of the hydraulic oil by up to 200°C and can help to extend the oil’s life, reducing costs by avoiding premature wear and degradation of components.

Hydraulic oil is continuously heated by friction between hydraulic system components and by climatic conditions. These factors generate excess heat which can be transferred to the hydraulic oil via an internal cooling system or by passing through a conventional radiator-style heat-exchanger. An oil cooler removes the surplus heat from the hydraulic fluid and transfers it to the cooling medium (either air or water) in a closed circuit, without the oil or cooling medium coming into direct contact with each other.

Bowman’s comprehensive range of hydraulic oil coolers are available in a choice of sizes to suit most applications. They can be supplied in a range of cooling media including air, seawater or distilled water with standard models suitable for use with water pressures up to 35 bar. In addition, sealing rings can be fitted to a number of the units, enabling easy maintenance and replacement of the cooling tubes without draining the hydraulic circuit. Computer aided selection software is also available to help identify the correct heat exchanger for a specific application.

There are two types of oil coolers in common use: air cooled and water cooled. Air cooled coolers typically resemble automobile radiators and operate by using a powerful fan to force ambient air over the pipe coils carrying the hot hydraulic oil. Water cooled units are usually ‘shell and tube’ designs with the oil-carrying pipes enclosed in a sealed shell through which cold water is circulated.

The most important thing to consider when choosing a hydraulic oil cooler is its ability to deal with the heat generated by the hydraulic system in question. Coolers can be either water cooled or air cooled and it is essential to ensure that the selected unit is capable of dealing with the heat load of the hydraulic system, as well as the environmental conditions where it will operate.

When selecting a marine oil cooler it is essential that it is correctly specified, installed, commissioned and maintained in order to provide the longest possible service life. This is particularly true where seawater is used for cooling, as the high velocity of seawater can rapidly erode Cupro-nickel alloy tube stacks and internal fins if the unit is not properly configured to meet the manufacturers recommended water flow rate. Bowman’s extensive range of marine oil coolers, all fitted with 316 stainless steel baffle plates and Cupro-nickel alloy tube stacks, is specifically designed for use in these conditions.hydraulic oil coolers