Bronkhorst EX-FLOW Mass Flow - Manual (Page 15)

BRONKHORST HIGH-TECH B.V.
2.4 Mounting
The mounting position depends on the type of meter. The preferred position is horizontal and at high
pressures (> 10 bar), Bronkhorst High-Tech B.V. strongly advices to mount the instrument in this position.
Avoid installation in close proximity of mechanic vibration and/or heat sources.
For mounting the F-106/F-107 series handle the following rules:
STRAIGHT PIPE LENGTH REQUIREMENTS (in number of diameters F)
Upstream Downstream
one 90° bend before meter 10 4
two 90° bend before meter 13 4
two 90° bend in two planes 20 4
three 90° bend in three planes 30 4
reduction before meter 10 4
expansion before meter 20 4
pressure reducing valve / control valve /
partially closed valve before meter
30 4
For further information see dimensional drawing.
In general flow straighteners have a suspicious influence on the free length of the meter.
A flow straightener can be imagined as a bundle of parallel tubes which is placed in the tube.
In general, these flow straighteners must be placed at least 6 à 8 D upstream of the meter.
In general, use a flow straightener in case of control valves and curves in unequal levels.
Next to these prescriptions for free length, the flow has to be steady, shock and pulsation free.
The flanges also must fit good to each other and there may not stick seals into the tube.
2.5 In-line filter
Although fluids to be measured should be absolutely free of dirt, oil, moisture and other particles, it is
recommended to install an in-line filter upstream of the flowmeter / controller, and if backflow can occur, a
downstream filter is recommended too. Be aware of the pressure drop caused by the filter.
On the inlet of some instruments a screen is placed to prevent foreign matter from entering the instrument
and to maintain a good flow pattern. This device cannot be seen as a filter element.
Contact your distributor for further information.
2.6 Gas connections
Bronkhorst High-Tech B.V. series mass flow meters/controllers are standard equipped with compression
fittings. For leak tight installation be sure that the tube is inserted to the shoulder in the fitting body and that
no dirt or dust is present on tube, ferrules or fitting. Tighten the nut fingertight; while holding the instrument,
then tighten the nut 1 turn. If applicable follow the guidelines of the supplier of the fittings.
Special types of fittings are available on request.
The flanges also must fit good to each other and there may not stick seals into the tube.
* Note: Always check your system for leaks, before applying fluid pressure. Especially if toxic, explosive or
other dangerous fluids are used.
9.17.028 page 15