SPM leonova emerald, Руководство пользователя

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Shock pulse measurement
D:5
D
Measuring points should be located directly on the
bearing housing, i. e. the metal that is touching the
outer race.
SPM supplies long adapters and transducers that allow
you to reach measuring points beneath covers, shields
and brackets.
The signal losses in the two unavoidable interfaces
(bearing – bearing housing and housing – adapter)
have been taken into account in SPM’s evaluation of
bearing condition.
The load zone is defined as the load carrying part of
the bearing housing. It is normally determined by the
weight of the supported machine part, i.e. the load
is mostly on the lower half of the bearing housing.
Consider also the direction of the force acting on the
shaft when the machine is running. Thus, belt tension
can determine the load on the bearings. The fan shaft
in point 3 is pulled down towards the motor. The drive
end of the motor shaft is pulled up towards the fan (2),
the non-drive end (1) is pressed down and away from
the fan. In point 4 the weight of the rotor normally
determines the measuring direction. The arrows show
the measuring points, numbered in the direction of
power transmission.
Finding the strongest signal
Use the shock pulse transducer with probe to find the spot on the bearing housing where the signal
is strongest. If there are several points yielding the same signal, select the point where it is easiest
to take readings.
When a measuring point cannot conform to the rules (because an ideal spot cannot be reached), make
allowance for a weaker signal. If you use SPM LR/HR, you have a COMP no. to compensate for weak
signals, but must still try to find a good point.