Hot Oil Pump
What is a hot oil pump?
A hot oil pump is a pump designed to circulate high temperature oil. It is most commonly used in thermal systems and vehicles where the circulation of oil provides lubrication for bearings and cooling. Hot oil pumps come in various types, with the most common being centrifugal, internal gear, and external gear. These pumps are designed to operate in harsh conditions and must be able to pump viscous fluids at temperatures up to 400 degrees Celsius without issue.
When the amount of heat that needs to be transferred from a system exceeds the capacity of water, the fluid used for heat transfer must be selected from synthetic oils derived from petroleum. If modern petroleum-based oils are used in a system, the feed fluid temperature can reach up to 300 degrees Celsius. The pump is a key component in all thermal systems.
The high temperature of the fluid imposes new requirements on the pump’s sealing system, especially during the initial filling of the pump and the first operation of the system. In other words, the pump used to circulate this oil must be able to withstand the high temperature of the fluid without any problems and operate at this temperature throughout its lifespan.
Features:
- Country of origin: Turkey
- Maximum pressure: 9 bar
- Body material: Cast iron
Features:
- Country of origin: Iran
- Maximum pressure: 8 bar
- Body material: Cast iron
Features:
- Country of origin: Iran
- Maximum pressure: 10 bar
- Body material: Cast iron
Features:
- Country of origin: Germany
- Maximum pressure: 10 bar
- Body material: Cast iron
Features:
- Country of origin: Germany
- Maximum pressure: 16 bar
- Body material: Cast iron
Features:
- Country of origin: Turkey
- Maximum pressure: 16 bar
- Body material: Cast iron
Operation of Hot Oil Pumps
The most common type of hot oil pump is the centrifugal pump. This type of pump consists of two parts: a moving part and a stationary part. The main part of the moving part is the impeller, which pumps the fluid by rotating and transferring energy to the fluid in this section. The main advantage of the centrifugal pump is the centrifugal force in the pump impeller, which increases the capacity to transfer energy to the fluid.
As shown in the figure below, the fluid enters the stationary part or diffuser after exiting the impeller. In this section, the fluid velocity decreases and its pressure increases, and finally, the fluid is transferred by the volute to the outlet manifold.
One of the designs proposed to improve the performance of centrifugal pumps is the magnetically driven pump. In this pump, magnets are used to drive the impeller. Using magnets eliminates the need for an external shaft and its associated sealing system, removing the possibility of leakage. This feature makes the magnetic pump ideal for transferring expensive, corrosive, toxic, and, in general, fluids that must be prevented from leaking. Also, this pump requires very little maintenance.
Another type of pump used as a hot oil pump is the gear pump. There are two different types of gear pumps for this purpose. The first type is an external gear pump. In the external gear pump, shown on the left side of the image below, two gears, one of which is a driver and causes the other gear to rotate, rotate in opposite directions. This rotation creates suction at the pump inlet and directs the fluid into the pump. Afterward, the fluid is confined between the housing and the gears and is driven toward the outlet in the indicated lines.
In the internal gear pump, shown on the right side of the bottom image, there are two internal and external gears. The number of teeth of the internal gear is one more than the number of teeth of the external gear. Therefore, by rotating the internal gear, the external gear rotates around the axis of the internal gear and pumps the fluid during rotation. Gear pumps can pump high-viscosity fluids without any problems; therefore, they are suitable for heavy oils. Also, the output pressure of this pump is high but is not suitable for high fluid flow rates.