In hydrometers, thermal expansion and contraction occur, so the resulting value will not match the density obtained from a oscillation type density meter. The relationship between the two values is as follows. (In API Std 2540/ASTM D1250, a program is prescribed for converting hydrometer density to the true density. The reverse calculation is performed using the formula below.)
S＝d/G
G＝1-0.000023×(t-15)-0.00000002×(t-15)×(t-15)
d:True density (g/cm3) at the measurement temperature t
S:Hydrometer density(g/cm3)
G:Correction coefficient for hydrometric thermal expansion and contraction
t:Measurement temperature (°C)
FAQDensity/Specific Gravity Meters
Density/Specific Gravity Meters
Q
What is the relationship between density values measured with a oscillation type density meter and with a hydrometer?
A
