Throughout the course of operation, pressurised hydraulic systems will generate heat through friction between system components. Unless adequately cooled, this thermal energy will cause the oil used within the hydraulic system to overheat and degrade, significantly shortening the life of the system. Cooling hydraulic oil coolers prevent this by reducing the operating temperature of the hydraulic fluid, keeping it at an acceptable working level.
The most common types of hydraulic oil coolers use water or air to cool the hydraulic fluid. They are essentially heat exchangers which work on the conductive transfer principle, with hot oil passing through a series of thin tubes exposed to a constant flow of lower temperature cooling medium. This allows the heat in the oil to be transferred into the cooling medium and shelved, typically shed into the atmosphere away from the hydraulic system.
Most systems will produce some level of thermal energy, which is unavoidable and must be cooled to prevent overheating. A high operating temperature can result in seal damage, excessive wear on surfaces and components, particulate formation and reduce system efficiency. This is why hydraulic oil coolers are a critical component of all hydraulic systems.
Hydraulic oil coolers are commonly found on commercial vehicles, such as HGV’s, LP Gas Transports/Bobtails, Maintenance Trucks and Utility & Agriculture Equipment. They are also a popular choice on stationary and slow moving mobile applications such as cranes, power generation and marine equipment.
Depending on the application and the environment, there are several different types of hydraulic oil coolers available, from air to water to shell and tube designs. Air cooled hydraulic oil coolers are most common, they look like a car radiator and operate by running the hydraulic oil through a coil or core of finned tubing, which is then cooled with ambient air from the side of the engine. Water cooled hydraulic oil coolers are also common and offer the advantage of operating with an internal flushing system, so they don’t require access to a power source.
Both the air and water cooled oil coolers are often fitted with seawater pumps that will pump filtered seawater through the hydraulic cooling system, effectively removing contaminants such as dust, grit and sand. It is important to ensure that the incoming seawater flows at a velocity and pressure that is within the manufacturers recommended parameters, otherwise the copper-nickel tubes in the hydraulic oil cooler will quickly erode, shortening their life span and causing system failure.
Providing a marine oil cooler has been correctly specified, installed, commissioned and maintained, there is no reason why it shouldn’t continue to operate reliably for decades. Bowman hear many stories of customers with marine oil coolers, that have been in service for 40 years and beyond, provided they have been properly cared for. To help ensure this, download our Bowman ‘Installation, Operation & Maintenance Guide’ for all the latest tips and tricks!