Flowmeter SVTU-11B, Operating Manual

Page: 23 / 68

23
For other FS the straight sections are included in delivery set according to customer’s
request.
Pipe branch with sleeve nut, which is included in delivery sets for FS of DN20 and
DN32, is a part of straight section and applied for further welding to pipeline to create re-
quired distance of straight section.
The axis of a branch pipe and straight section should be a uniform coaxial line without
significant jogs and bends. Transition ‘jump’ from a branch pipe to a pipe should not exceed
0.5 mm (± 2.5%) for FS of DN20 and 0.8 mm (± 2.5%) for FS of DN32
9.4.1.3 While installing FS-20 (FS connection to welded pipe branches with sleeve
nut) its position should be fixed (to prevent a revolution) by a screw driver S = 30 mm,
which is based on special faces of FS (see figure in Appendix L).
It is strongly prohibited to apply another place of FS to prevent FS revolution (PS
connectors, FS body, faces with marking).
For tightening a sleeve nut the screw driver S = 41 mm should be applied.
9.4.1.4 While connecting flow meter’s flange to the pipe, the flange bore can be
reamed to external pipe diameter with the least allowable tolerances. The schemes for flange
welding are given in Fig. 9.2 and Fig. 9.3.
Flange mounting to the pipeline should be carried out without metal sagging on the in-
ternal pipe surface. Otherwise change of velocity profile can lead to additional meter error.
After flow meter installation the flange painting should be done.
Figure 9.2 Figure 9.3
WARNING!
Please avoid welding of flanges to the pipeline if FS has been installed! It can lead to flow meter
damage because of overheating.
9.4.1.5 Pressure loss on flow measurement sections
Pressure losses at maximal flow rate Qmax don’t exceed 0.085 kgf/
с
m
2
(for all flow
meters, if there are no additional remarks).
Pressure loss for flow meters of DN20 in kgf/
с
m
2
is shown on the plot (see fig. 9.4)