Ultraflux Uf 841, User Manual

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NT UF 841 CP GB (d) / June 2015
4.4 Installing probes and connectors
The care taken to install the probes (sensors) and their alignment determines the accuracy of the flow
measurement.
4.4.1. Permanent external (clamp-on) probes
1) Preparing the pipe
To install external probes (clamp-on), the areas of pipe where the sensors are to be installed must have
been carefully cleaned beforehand. The pipe must be cleaned using absorbent paper or a piece of cloth. If
the pipe is very dirty or corroded, use a metal brush or scraper. It is not necessary to remove good
paintwork. It is even recommended to keep it to avoid corrosion. The same applies to most plastic
coverings. On the other hand, if the paint is blistered or flaky (test by scratching with your nail or a pointed
tool), it should be removed locally.
Then coat the locations where the probes are to be installed lightly with grease (do not use silicon grease).
2) Installing the elastomer strip
To start, cut a piece of strip to the size of the probe (+5 mm).
Then remove the plastic protective film.
Apply the strip where the probe is to be installed.
Lastly, lightly grease the external surface of the strip.
3) Installing the probe
Place the probe on the strip and fix it in place by firmly tightening the stainless steel collar supplied.
Preferably position the collar locking screw on the opposite side to the probe.
4.4.2. Temporary external (clamp-on) probes
1) Preparing the pipe
To install external probes (clamp-on), the areas of pipe where the probes are to be installed must have been
carefully cleaned beforehand. When doing this, take into consideration the distance between the probes and
estimate the space required for probe/mounting assembly. The pipe must be cleaned using absorbent paper
or a piece of cloth. If the pipe is very dirty or corroded, use a metal brush or scraper. It is not necessary to
remove good paintwork. It is even recommended to keep it to avoid corrosion. The same applies to most
plastic coverings. On the other hand, if the paint is blistered or flaky (test by scratching with your nail or a
pointed tool), it should be removed locally.
2) Selecting and installing the coupling medium
A coupling medium must be selected which is suited to the humidity and temperature conditions of your
application.
- "traditional" gel for temporary measurements at ambient temperature and without too much humidity,
- high temperature gel (<300°C),
- grease in the case of high humidity (quality depending on temperature).