Venturi as cast
For a better precision
GENERAL DATA
- Standards: ISO 5167-1 & 4, ASME MFC-3M.
- Solder (BW) or flanged connection
- Material: Standard: carbon steel, stainless steel, others according to your application.
- Fluid: liquid, gas, steam.
- Diameter of pipes: from 100 to 1,200 mm.
- Accuracy: 0.7% of max flow.
- Repeatability of the measurement: 0.1%.
- Upstream and neck pressure points: annular chamber or individual plugs connected in "triple T".
| ISO 5167-1&4 | ASME MFC-3M | ||
|---|---|---|---|
| ReD | Reynolds number in pipework | 2.105 ≤ ReD ≤ 2.106 | 2.105 ≤ ReD ≤ 6.106 |
| D | Pipe interior diameter | 100 mm ≤ D ≤ 800 mm | 100 mm ≤ D ≤ 1 200 mm |
| β | d/D | 0,30 ≤ β ≤ 0,75 | |
| Ra | Roughness at the throat | Ra ≤ 10⁴.d | |
| Roughness input and convergent cylinder | Ra ≤ 10⁴.D | ||
| l | Minimum inlet cylinder length | l = D ou (0,25.D + 250 mm) | |
| l' | Convergent input length | l' = 2,7.(D - d) | |
| α | Convergent angle of entry | α = 21° ± 1° | |
| lc | Throat length | lc = d ± 0,03.d (minimum value = d/3) | |
| R1 | Radius of curvature 1 between the input cylinder and the convergent | R1 = 1,375.D ± 0,275.D | |
| R2 | Radius of curvature 2 between the convergent and the throat | R2 = 3,625.d ± 0,125.d | |
| R3 | Radius of curvature 3 between the throat and the divergent | 5.d < R3 < 15.d | |
| φ | Diverging angle of exit | 7° ≤ φ ≤ 15° | |
You can find below our most frequently asked questions / answers.
If you do not find the answer you are looking for, please contact us either by phone at +33 (0)5.59.30.85.20 or via the contact form. We will respond as soon as possible.
When to choose a venturi tube "as cast"?
What about the venturi "as cast" with machined convergent?
The convergent of a venturi "as cast" is normally poured into a sand mold to obtain an ideal surface finish and the intersections between the cylinder and the cones are rounded. It is thus possible to obtain a measurement accuracy of about 0.7% of the maximum flow rate. However, for reasons of quantity (the molds are generally made for large series), we often realize venturis "as cast" with a machined convergent. The measurement accuracy obtained is then of the order of 1% of the max flow.
