head pressure oil versus water in psi
head pressure oil versus water in psi
(OP)
Hello, I'm in need of a head pressure factor for 1' of water versus 1' of oil (say, 30 weight viscosity) . I have found a factor of .43 psi for 1' of water and oil is less dense than water so I know the figure should be less than .43 psi. Any help on this matter would be appreciated. I don't have a specific gravity on the oil either although I suspect it is around .90 (1.0 for water)Thanks, John





RE: head pressure oil versus water in psi
If s.g. is 0.9, the PSI/ft = 0.433 x 0.9 = 0.39
RE: head pressure oil versus water in psi
SG = 141.5 / (131.5+APIGravity)
so 30 degree API crude would be
SG = 141.5 / (131.5 + 30) = 0.876
Which makes the hydrostatic gradient:
Gradient = 0.43 * 0.876 = 0.377 psi/ft
Now what I don't know is if SAE 30 weight is similar to the API 30 degree crude (I typed the above before I realized that you had asked about 30 weight, not API grades and thought it might be useful to leave it).
David
RE: head pressure oil versus water in psi
SG=0.912
BigInch
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http://virtualpipeline.spaces.msn.com
RE: head pressure oil versus water in psi
using SG 0.912
1 x 0.912 / 2.31 = 0.398 psi
RE: head pressure oil versus water in psi
It all depends on the accuracy required. When speaking of density of liquids (ρ) it would be better to state the temperature. For oils these are:
ρr, kg/m3, is the density at the reference temperature Tr, [K]
k is an exponent of temperature-density dependence (typically = 0.001/K)
A grade 50 base oil could also have a density of 888.7 kg/m3 at 10oC, while that for water would be 999.2 kg/m3 resulting in a ratio of 0.8894.
The ratio at 60oC, would be 0.8787.
RE: head pressure oil versus water in psi
BigInch
-born in the trenches.
http://virtualpipeline.spaces.msn.com