11
Performing measurements
Before checking steam traps, make sure that the
measurement sensitivity of the VKP 10 has been
selected in advance using the rotary switch 7.
The switch position “10” indicates the highest
level of sensitivity. Different steam trap types
generate varying sound levels, even when the
loss of steam and operating conditions are iden-
tical. We recommend the switch position “8” for
GESTRA type-BK steam traps and position “7” for
type-MK models.
Lightly press the sound probe against the surface
of the steam trap. Always place the sound probe
at the same location on the housing when testing
steam traps of the same type. This makes it pos-
sible to compare the steam traps and determine
any changes when repeating the tests.
Steam traps operating continuously, and dis-
charging up to about 30 kg/hr of condensate
from steam pressures lower than 20 bar will
cause no or only a slight deflection of the indicat-
ing meter. Any steam loss is indicated by a pro-
portional meter deflection. The relation between
steam loss and meter deflection depends on the
steam trap type and the used measuring point
on the trap surface. Larger condensate flowrates
and higher service pressures result in louder
flow-generated noises, making it necessary to
reduce the sensitivity setting. To obtain meaning-
ful readings when using the VKP 10, log and use
installation-specific survey data and empirical
test values.
In practice, an exact quantification of the steam
loss is usually only of minor importance. Normal-
ly, an approximate value that allows the detection
of steam loss through steam traps at a tolerable
effort will suffice.
When checking the steam traps, set the rotary
switch to “7” or “8”. A continuous indication be-
tween 6 and 8 on the meter scale indicates that
the trap requires maintenance or replacement.
This indicates steam losses of 1 to 4 kg/hr.
