Flowmeter SVTU-11B, Руководство по эксплуатации

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For FS-50 pressure loss is resulted in fig. 9.6.
Figure 9.6
9.4.2 Installation of flow sensors
9.4.2.1 The order for installation of flow sensors FlS listed below is applied for FS
of DN 32… DN150.
FS of DN20 is delivered with installed and sealed flow sensors FlS, their dismantling
can be done only at manufacturing company.
9.4.2.2 After installation of flow measurement section ultrasonic flow sensors
should be installed as follows:
−
clean internal surfaces of bushes from dust and dirt if necessary;
−
for protection of fixing nut and flow sensor materials from diffusion with material of
FS it is necessary to grease a bush thread and a lateral cylindrical surface of ultrasonic flow
sensors with graphite greasing;
−
FlS effective area (edge) should be cleaned from greasing;
−
insert ultrasonic flow sensors in bushes (pipe-bends) of flow measurement section.
Marking is put on sensor cable outputs. So FlS with marks “11” (or “21” for the second flow
measurement channel) should be inserted
in first (according to flow direction) FS bush,
FlS with marks “12” (or “22” for the second flow measurement channel) should be inserted
in second (according to flow direction) FS bush;
−
at tightening of flow sensor’s fixing nut the force put to a wrench should be equal to
40 … 45 N·m and provide a ‘zero’ gap between FS surface and FlS ring surface outside of
its sealing gasket. For FlS installed in FS of DN32 the force is 18 … 20 N·m.
0
0.05
0.1
0.15
0.2
0.25
0.3
0 20 40 60 80
P
,
k
gf
/cm
2
Flow rate, m
3
/h