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Multi-bore orifice plates
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Except for all advantages of centric orifice plates
(such as simplicity, replaceability, reliability), multi-bore
orifice plates have lower built-in lengths enabling wider
possibilities of their use. Design of multi-bore orifice
plate enables using of straight lengths in front of and
behind orifice plate in length of 2D or max. 3D in
dependency on b coefficient (D
symbol indicates inside diameter of piping). There is a
similarity with centric orifice plates, however, in the
plate there are more bores. |
Flow of measured medium through several narrowed
diameters make lower demands on minimal straight lengths of piping
in front of and behind the plate which are essential for proper
functioning of these meters. Use of multi-bore orifice plates is
limited only by b coefficient (b=d/D).
Multi-bore orifice plates are ready for use as working meters
without verification or as verified meters with meter tube included.
These meters have its own pattern approvals which are in compliance
with ISO 5167 and ISO TR 15377 standards.
Multi-bore orifice plate are manufactured for
DN15-DN1000 inner diameters for a range of b
coefficient limited by b=0,4 and
b=0,65.
Multi-bore orifice plate with chamber tapings of pressure
differential as working meter without verification
Multi-bore orifice plate with chamber tapings (as working
meter without verification) is manufactured in range of nominal
inner diameters DN15-DN1000. Its main part is made of two-part
flange with annular chambers and a plate. Plate is clapped
between two parts of flange and it is sealed by a seal. In the
flanges there are outlets of differential pressure tappings.
Plate is replaceable. Working position of flow meter can either
be horizontal or vertical. Usual construction width of orifice
plate with chamber taping is 60 mm.
flow
direction |

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Diagram of multi-bore orifice plate with chamber
tappings of pressure differential |
For the production of flange used for multi-bore
orifice plates we usually use 11 grade or 17 grade steel. Plate
is manufactured of 17 grade steel. On request we can make plate
or flanges of special materials such as nickel and titanium
based alloys event. tantalum.
Multi-bore orifice plates as working meters without verification
can also be delivered with ANSI B 16.36 pressure taping flanges.
Multi-bore orifice plate with individual tapings of pressure
differential as working meter without verification
Multi-bore orifice plate with individual
tapings as working meter without verification is manufactured
in range of nominal inner diameters DN 15-DN 1000. This type of
orifice plate has one-piece flange and plate is placed directly
in the orifice plate body. Individual tappings are made in front
of and behind plate. Multi-bore orifice plate can be used in
metering places with higher operational pressure nad temperature.
Due to the fact that the orifice plate is unreplaceable, there
is lower probability of leakage. Plate can not be replaced.
Working position of the flow meter can either be horizontal or
vertical. Usual construction width of orifice plates with
individual tapings is 40 mm.
flow
direction
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Diagram of multi-bore orifice plate with individual
tappings of pressure differential |
Multi-bore orifice plate with individual
tapings is made of 15 or 17 grade steel. On request it can also
be made of special nickel and titanium based alloys event.
tantallum.
Multi-bore orifice plate with verification
Verified multi-bore orifice plate is
manufactured in design of meter tubes containing not only built-in
orifice plate (flange joint incl. distance bolts) but also
straightening section of piping in front of and behind orifice
plate ensuring supply of stabilised fluid flow. Meter tube is
manufactured for all nominal inside diameters with corner
pressure tapings in the flange.
Meter tubes are manufactured in the range of nominal inside
diameters DN15-DN1000.
Working position of the flow meter can either be horizontal or
vertical. For the meter tube there can be used pattern approved
readers (indicators) of differential pressure, pressure reader,
thermometers and evaluation units.
For production of meter tubes we usually use 11 grade steel. It
can also be made of 15 and 17 grade steel as well as of plastic.
Plate is usually made of 17 grade steel. Plate is carefully
centred between taping flanges by simple construction placing.
Diagram of plates
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flow
direction
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Plate for DN15-DN200 meter tube |
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flow
direction
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Plate for DN250-DN1000 meter tube |
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Diagram of meter tubes with multi-bore
orifice plate
flow
direction
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Diagram of DN15-DN200 meter tube |
flow
direction |

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Diagram of DN250-DN1000 meter tube |
Dimension table of meter tubes with multi-bore
orifice plate
Nominal inside
diameter and
nominal pressure
of meter tubes |
Outside
diameter
of piping
(mm) |
Thickness
of piping
(mm) |
Inside
diameter
of piping
(mm) |
Outside
diameter
of flange
(mm) |
Weight
of meter
tube
(kg) |
Approximate
construction
length of meter
tube approx. (m) |
| DN 15 |
PN 40 |
21.3 |
2.6 |
16.1 |
95 |
3.2 |
0.11 |
| DN 20 |
PN 40 |
26.9 |
2.6 |
21.7 |
105 |
4.5 |
0.14 |
| DN 25 |
PN 40 |
33.7 |
2.6 |
28.5 |
115 |
5.1 |
0.16 |
| DN 32 |
PN 40 |
42.4 |
2.6 |
37.2 |
140 |
7.1 |
0.20 |
| DN 40 |
PN 40 |
48.3 |
2.6 |
43.1 |
150 |
9.1 |
0.23 |
| DN 50 |
PN 40 |
60.3 |
2.9 |
54.5 |
165 |
17.9 |
0.28 |
| DN 65 |
PN 40 |
76 |
3.2 |
69.6 |
185 |
25.1 |
0.34 |
| DN 80 |
PN 40 |
89 |
3.6 |
81.8 |
200 |
29.8 |
0.40 |
| DN 100 |
PN 40 |
114 |
4 |
106 |
235 |
43.6 |
0.50 |
| DN 125 |
PN 40 |
140 |
4.5 |
131 |
270 |
61.8 |
0.60 |
| DN 150 |
PN 40 |
168 |
5 |
158 |
300 |
70.2 |
0.72 |
| DN 200 |
PN 40 |
219 |
6.3 |
206.4 |
375 |
128.5 |
0.93 |
| DN 250 |
PN 16 |
273 |
7 |
259 |
405 |
95.7 |
0.67 |
| DN 250 |
PN 40 |
273 |
7 |
259 |
450 |
191.4 |
0,74 |
| DN 300 |
PN 16 |
324 |
8 |
308 |
460 |
102.9 |
0.78 |
| DN 300 |
PN 40 |
324 |
8 |
308 |
515 |
258.2 |
0.86 |
DN 350-1000
PN 16-40 |
Inside diameters
of piping are
determined by discussion with customer |
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