# Having trouble understanding effect of hydraulic fluid density.

#### hellocubed

##### Full Member
I understand that the equation for pressure in a hydraulic press is P=F/A
And density of fluid does not effect this.

But im having trouble conceptualizing this.
If the hydraulic fluid was thick syrup instead of oil, it would be much more difficult to press down on the press...
The increased difficulty of pushing down a press, if thats not pressure, what is it? It seems to be an increase in force applied.

#### johnnydrama

##### I'm no Superman
15+ Year Member
I understand that the equation for pressure in a hydraulic press is P=F/A
And density of fluid does not effect this.

But im having trouble conceptualizing this.
If the hydraulic fluid was thick syrup instead of oil, it would be much more difficult to press down on the press...
The increased difficulty of pushing down a press, if thats not pressure, what is it? It seems to be an increase in force applied.

It's similar to friction, it would only really apply while things are moving. In a steady state, viscosity shouldn't matter (imagine everything's already where it's supposed to be and the pressure you're applying is just to keep it there, not to move it).

#### chiddler

##### Full Member
10+ Year Member
I understand that the equation for pressure in a hydraulic press is P=F/A
And density of fluid does not effect this.

But im having trouble conceptualizing this.
If the hydraulic fluid was thick syrup instead of oil, it would be much more difficult to press down on the press...
The increased difficulty of pushing down a press, if thats not pressure, what is it? It seems to be an increase in force applied.

It would be more difficult to push on it because of the viscosity, yes. But think about it this way. Don't push on it. Put a weight on it instead and leave it for 20 minutes. Now what do you think will happen?

The difference is that it'll just take longer to reach, as above poster said, steady state with a viscous fluid.

This thread is more than 9 years old.

Your message may be considered spam for the following reasons: