Why Does Hydraulic Oil System Heating?

A last possibility is an excessive wear which leads to high leakage and thus to high temperature.

Dear Mukesh,

Is there a possibility that a fin type cooler / radiator meant to cool hydraulic oil on return path is not working properly and the hot oil is getting circulated into the system.

Thanks and regards

Aniruddha

I will go and check on the hydraulic pump bearing

Hello,

What is the name of the machine manufacturer and the model? Do you have a hydraulic circuit diagram? What sort of power input are we talking about? More details needed to give any sort of useful answer.

Oliver Dunthorne

Hydraulic Engineer.

The schematic diagram will give better idea for analysis. anyway the following step wise analysis will help you.

1. check your cooling system first, check filter if you have circulation pump with cooler. Then check the heat exchanger inlet and outlet temperature if you have.

2. Check the relief valves in the circuit.

3. If the system connected to different manifolds or actuators, check the temperature difference between P line and T line of each manifold or subplate. Some T line temperature may be abnormal.

4. The temperature raise may be result of internal leakage of cylinder or excess case drain of motor or some times internal leakage of spool valve.

hope you have checked the oil quality. More information/ data required to provide a solution.

Pump forces hydraulic fluid To flow, thus some energy of pumping converts into heat, which increases fluid's temperature. If the components of hydraulic system are activated more often then more heat is released and higher temperature of fluid. Though the oil is cooled, when entering back into tank that sometimes has a cooling system, its temperature should be kept at certain level to assure proper viscosity. It might be that the hotter hydraulics is hotter by design, but it might be that the activation of components is on a higher frequency level than originally intended.

Please observe that pump's motor heats up when the pump pumps more fluid, but if it pumps less fluid, the temperature of fluid increases and the motor cools down. Thus every hydraulic pump has "working/not working" time cycle and that is because of the problem you have noticed.

In addition the speeding up of technological process without correcting the operation cycle of hydraulics could cause the heating.

80 degree is not a big deal for hydraulic fluid, but if you feel not comfortable then check the filters and clean them if necessary.

Another thing also is. Do you have alot of sharp bends such as 90 degree fittings or are your restricting it before it goes to the tank.