Operating Instructions
OIO 15en Edition 2020-05
23
Installation
Installation, removal and connection
► During the installation of the flowmeter observe the recommendations for the installation variants
and avoid error sources, see "Installation", page 21.
Protect the flowmeter against soiling
KRAL flowmeter as rotating displacement meters need pure liquids for operation. In case of impurities,
solid content or abrasive fine particles in the liquid during operation, the flowmeter has to be protected
additionally by a correspondingly dimensioned operating filter in the pipe system. The mesh width of the
operating filter depends on the size of the flowmeter.
Tab. 1 Mesh width of the operating filter
Pipe thread connection
The screw-in length of the piping may not exceed the threaded length of the flowmeter, since the flow
cross-section is narrowed and internal components can be damaged.
Flanged connection
The flowmeter connections to the pipe system must be stress-free, as otherwise there is no guarantee
that the flowmeter will operate safely. The following drawings show how a flange is connected stress-
free to the flowmeter.
CAUTION
Measuring error through air in the pipe system and/or incorrect installation of the flowmeter.
► In the case of horizontal installation of the flowmeter at the highest point of the pipe system an air
pocket can arise that results in measuring errors.
► Vent the pipe system thoroughly before commissioning.
► At a vertical installation of the flowmeter and the flow direction from top to bottom ensure that the
liquid does not flow freely out of the flowmeter, for example by routing the pipe upwards or by
reducing the pipe diameter with a reducer.
Flowmeter size
Mesh width max. [mm]
OME 13
0.1
OME 20
0.1
OME 32
0.25
OME 52
0.25
Fig. 2
Correct flange connection
