K-Patents PR-01-S - Manual (Page 23)

INSTRUCTION MANUAL FOR K-PATENTS PR-01-S (-AX/FM/CS) DOCUMENT/REVISION No. INM 1/14
Effective: May 15, 2009
21
Selection of location
To decide "Where to mount" use the following criteria:
1. Process pipe is preferred to process vessel, because favorable flow conditions are difficult to
ensure in a vessel.
2. If the process pipe diameter varies, select the position with the smallest diameter (and
accordingly highest velocity). Then the prism keeps better clean. If the pipe is coned up after a
pump, valve or magnetic flow meter, then add a length of straight pipe before the coning up and
mount the refractometer there.
3. If the refractometer is used in a feedback control loop, make the time lag small. E.g. when a
dilution valve is controlled, mount the refractometer as near the dilution point as possible.
4. If the temperature varies along the process pipe, select the position with the highest temperature.
Then the risk of prism coating is minimized, because higher temperature means higher solubility
and also lower viscosity.
5. Often the position with the highest pressure (= low point in pipe system + after pump + before
valve) has favorable flow conditions without sedimentation or air trapping risks.
6. The sensor should be conveniently accessible.
3.2. MOUNTING EXAMPLES
For mounting drawing for desired pipe diameter and connection type, contact the representative of
K-Patents.
No special mounting parts are needed to mount K-Patents Process Refractometer. For all process pipe
diameters just a standard piece of 88.9 x 3.6 steel pipe is used as adapter. For small process pipe diameters
the piece of pipe is sealed in the other end to form a flow cell. Examples for different process pipe
diameters are given in Figure 3.20 and Figure 3.21.
For flanged mounting, the user has to provide the counter flange. For clamp mounting K-Patents provides a
weld-on ring.
Flow cells can be supplied by K-Patents, see Section 8.5.