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Orange Research 2020 Series Fixed-Orifice Flow for Low Flow Rates Liquids or Gases

Fixed-Orifice Flow for Low Flow Rates Liquids or Gases
2020 Series

Our fixed-orifice flowmeters are designed for low flow applications, from 0-2 to 0-40 GPH. Like our variable-area flowmeters they are built from solids blocks of metal making them a favorite for high line pressure applications, to 3000 psi. You will find many in hydraulic and pneumatic systems.

Though rugged, they maintain the sensitivity required for low flow measurements.We use a fixed Delrin orifice centered on a spring-loaded Buna-N diaphragm-magnet sensor, which provides sensitive responses to changes in flow. This diaphragm sensor is magnetically coupled to a pointer, which relays the flow rate onto an easy-to-read square-root calibrated dial.

These in-line flowmeters often replace rotameters, which have small scales that can be difficult to read, especially with dirty or opaque fluids. Our 2.5 to 4.5 inch dials with large, bold markings can be read from a distance. The spring-loaded sensor allows them to be oriented either horizontally or vertically. Many others must be mounted vertically only, limiting space and design flexibility.

We offer them with pressure bodies (and wetted parts) of aluminum or stainless steel. Choose from a wide selection of standard options such as liquid filled dials, reverse flow, red arc scales and many more. More details on these models can be found in our flow introduction pages 16-19.

Reed switches and relays can accompany the meters or be supplied on their own, without a dial. Electrical details are on pages 26-27.

• Large, easy-to-read dial
• Rugged, high line pressure design
• Vertical or horizontal mounting

Select a link under the "item" tab below to order.

Table 1Table 2Table 3Table 4Table 5Table 6Table 7
Table 1Model
Table 2Flow Body.
1C316 SS
Table 3Dial Case
2.5B2.5” basic
3.5B3.5” basic
4.5B4.5” basic
Table 4Electrical
A-A2 ea. -A
B-B2 ea. -B
C-C2 ea. -C
Table 5Calibration
Wstd. calibr. -water
Ostd. calibr. -oil
Astd. calibr. -air
Sspecial calibr.*
Table 6Options
5plastic lens
6liquid fill (glycerine)
8reverse flow
9vertical flow (specify direction – up or downward)
Table 7Special Seals (Buna-N standard):
Model 2021FG/FGS/FS
Flow range
Liquids 0-2 to 0-40 GPH
(0-8 to 0-150 LPH
Air & Gas 1.5-5 SCFM (60-140 SLPM)
Porting 1/4" NPT
Maximum line pressure/temperature 3000 psig (200 bar)
200˚F (93˚C)
Accuracy (F.S.)/repeatability
Liquids 2%/1%
Air & Gas 5%/1%
Turndown 3:1
Electrical Available 2 switches

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