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The temperature correction for different kinds of oil and
kg
oil products varies from 0.0009 to 0.0005 .
о 3
С m

6.3 Equipment, devices and materials

The following equipment, devices and materials should be used
for the experiment: areometers (float densimeters); pycnometers of
3
3
volume 25 сm 3 (50 сm , 100 сm ); analytical balance; water

thermostat (the measuring cylinder for creation of water bath) of
3
volume 500 сm ; measuring cylinder; the samples of formation

water, oil, gas condensate and oil product.
An areometer (figure 6.1) is a hollow cylindrical glass float. It
is tightly closed. It has the constant mass. Being in the liquid, the
areometer submerges for a different depth depending on the density of
this liquid. There is a scale for determining the density of liquid in

the upper (narrow) part of the device. There is a thermometer in the
lower part of the areometer (sometimes) and there is a mercury or
leaden load on the bottom of the device. Due to this load the

areometer submerged into liquid is in vertical position. Areometer
application is based on the principle of Archimedes. The density of
liquid can be determined by the depth of areometer immersion.
In laboratories the areometers with the scale which shows
3
3
the magnitude of density in g/сm or kg/m are used. By means of
float densimeters densities of liquids more light and heavy than
3
water in the range from 0.650 to 2 g/сm are determined. The scale
of float densimeter is graduated at 20 °С as well as the same of

areometers.
Pycnometers (figure 6.2) are used for determining the density of
liquids, powder substances and gases. They are the glass capacities
with thin walls graduated on the mouth. There are pycnometers of
3
volumes 25, 50 or 100 сm . The main advantage of pycnometer
method is simplicity and that it enables to determine the density of
3
tested liquid of a very small volume (less than 100 сm ). The accuracy
of pycnometer is 0.0001. There are also pycnometers with capillary

tubes with graduation marks (for more accurate density measuring).
Besides areometers, float densimeters and pycnometers, special
densimeters of different constructions (hydrostatic, piezometric and

others) and hydrostatic scales are also used to determine the density of

liquid.

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