K-Patents PR-33-AC - Manual (Page 15)

3 Refractometer mounting 9
© Copyright K-Patents 2014. All rights reserved.
3 Refractometer mounting
The Sanitary OEM Refractometer mounting location should be chosen with care to en-
sure reliable readings from the process.
3.1 Choosing the refractometer mounting location
The mounting location needs to be such that sediments or gas bubbles cannot accumu-
late by the refractometer. Good flow velocity is essential in keeping the prism clean.
Important: If the process pipe vibrates, support the pipe. A vibrating pipe might dam-
age the in-line refractometer mounted on it.
The refractometer cover should not be exposed to high temperature radiation. In most
cases, draft and natural convection provide sufficient air cooling if the air gets to flow
freely around the refractometer head.
Important: Always mount the refractometer so that the interconnecting cable points
downwards from the refractometer head.
3.2 Check list for pipe mounting
Most Sanitary OEM Refractometers are mounted in a pipe. K-Patents recommends
a flow velocity between 1 and 3 m/s (3–10 ft/s). If the flow velocity exceeds 6 m/s
(20 ft/s), there is a risk of cavitation. Cavitation may damage the sensor and the piping.
Too slow a flow velocity may cause erraneous measurement readings due to coating of
stratification (layering) of the sample on the prism.