Oval Smart EX DELTA II Series, Instructions Manual

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D-582-3-E
5. 配管要領
一般的な注意事項は、JIS Z 8766 『渦流量計による流量測定方法』をご参照ください。
5.1 標準配管条件
（注記） 下流側には、必ず５D以上の直管部を設けてください。
D ＝ Nom. Dia.
No. Remarks
Flow Straightener
12D
Flow
See page 50 for face-to-face
dimension.
Table 5. Straight Pipe Lengths Recommended by ISO-5 D ＝ Nom. Dia.
No. Remarks
１ Reducer
15D min.
Flow
A concentric reducer is upstream of meter.
２ Elbow
23D min.
Flow
An elbow is upstream of meter.
25D min.
Flow
Two elbows are horizontally upstream of
meter.
40D min.
Flow
Two elbows are vertically upstream of meter.
３
Gate Valve
Fully Open
15D min.
Flow
Fully open
A full-open gate valve is upstream of meter.
４
Gate Valve,
Partially Open
50D min
Flow
Partially open
A partially open gate valve, a narrow orifice,
or something that considerably disturbs the
flow pattern is upstream of meter.
5. PIPING INSTRUCTIONS
For general consideration, see JIS Z 8766, "Flowrate Measurement Methods with Vortex Flowmeters".
5.1 Standard Piping Conditions
It is generally required that the flow pattern of a material moving into an inferential type meter be as
uniform as possible for accurate metering. Accordingly, proper flow straightening measures must be
taken when the application engineer considers installation of a DELTA meter. In applications where OVAL
straightening devices (flow straightener, and downstream pipe) are used, a straight pipe section is not
required unless otherwise specified. But if you plan to solve the flow pattern problem with a straight pipe
section alone, secure the length of a straight pipe conforming to the ISO standards given in Table 5.
below:
(1) OVAL flow straightener combined with downstream pipe
(2) Straight pipe alone without flow straightener