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Without removing the viscometer from the thermostat
and closing the wide knee of the viscometer with a finger,
compressing the pears suck the fuel into the expansion slightly
above the M1 mark. At the same time, they ensure that in the
capillary and expansion there are no bubbles of air, ruptures
and films.
Subtracting from a wide knee, watching the flow of fuel.
When the fuel level reaches the top mark M1, the stopwatch
will be switched on and stopped when the fuel level goes below
the M2 mark. Record the time of leakage of fuel in seconds.
Experiments are repeated three times.
The leakage time for each experiment should not differ
from the arithmetic mean by more than 0,5 %.
Kinematic viscosity of the studied diesel fuel is calculated
by the formula:
v    c , (9.1)
20
where с – constant a viscometer, which depends on the
geometric dimensions of the viscometer and is given in the
2 2
manufacturer's passport., mm /s ;  – arithmetic mean time of
fuel leakage through the capillary, s.
The kinematic viscosity of the studied diesel fuel is
recorded in Table. 9.1.

Table 9.1 - Value of kinematic viscosity of diesel fuel
brands
Rate for brands Rate for brands The
Indicator (DSTU 4840-2007) (DSTU 3268-99) leading
diesel fuel
А-F S W diesel
Kinematic
viscosity
2,0…4,5 3,0…6,0 1,8…6,0
at 20С,
сSt
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