Ordering Guide
How to Order a Flo-Gage™ Flow Meter
Build your model number in seven steps — body size, series, material, flow direction, full-scale flow rate, options, and switches. Not sure where to start? Use the Product Selector or call us.
About the Flo-Gage™ Flow Meter
The RCM Flo-Gage™ is a direct-reading flow meter with a large, easy-to-read 3.5″ (90mm) 270° analog dial calibrated in engineering units such as GPM, SCFM, and L/min. Flow is measured based on a pressure differential created across a built-in calibrated nozzle — the meter is self-contained and complete, requiring no external power, separate orifices, blocking valves, purging valves, or equalizing valves.
Suitable Fluids
- Water, oil, and most low-viscosity liquids
- Compressed air and oxygen
- Carbon dioxide and inert gases
- Saturated steam up to 120 psig (Option K)
Key Features
- Sturdy in-line metal construction
- Black-on-white dial, easy to read over time
- ±3% full scale accuracy over a 6:1 range
- Factory configured for quick installation
- Field reconfigurable if needed
- Suitable for opaque and clear fluids
Specifications
| Specification | Standard | Optional |
|---|---|---|
| Housing | Polycarbonate | Aluminum |
| Body | Bronze | Monel, 316 Stainless Steel |
| Bellows | Bronze | Monel, 316 SS, Inconel |
| Seals | Buna-N | Viton (A), EPR (B), Teflon (B2) |
| Dial Crystal | Polycarbonate | Glass, Plastic |
| Gear Movement | Bronze | 316 Stainless Steel |
| Accuracy | ±3% Full Scale | — |
| Repeatability | ±1% Full Scale | — |
| Max Pressure | 180 psig | 400 psig (Option H) |
| Min Pressure | 10 psig | — |
| Max Temperature | 212°F (100°C) | 350°F (177°C) |
| Min Temperature | -30°F (-34°C) | -80°F (-62°C) |
| Liquid Flow Range | 4 GPH – 3,000 GPM | ES option for < 2 GPM |
| Gas Flow Range | 40 SCFH – 20,000 SCFM | Option I required |
Seven-Step Ordering Sequence
Body Size
Pipe size at the meter inlet (e.g., ½″, ¾″, 1″, 2″, 4″, 8″).
Series
Series 7 = Threaded (FNPT standard). Series 8 = Wafer (mounts between 150 or 300 lb class flanges).
Body Material
Code 1 = Bronze · Code 2 = Monel · Code 3 = 316 Stainless Steel.
Flow Direction
L, R, VUL, VUR, VDL, or VDR — see the direction guide below.
Full Scale Flow Rate
Full scale GPM for liquid meters; full scale SCFM for gas meters. Prefix with "M" for metric units. Use Option E for non-standard flow rates.
Options
Add option codes for seals, case style, service type, transmitters, and more (see the full options table below).
Switches
Add reed switch codes (1S2 or 2S2) if high/low flow alarm contacts are needed.
Ordering Example
b) Series — Threaded vs. Wafer
Series 7000 — Threaded
- FNPT connections standard
- Sizes ¼″ to 3″
- FBSP threads available on request
Series 8000 — Wafer
- Mounts between 150 or 300 lb class flanges
- Sizes ½″ to 8″
- No flange drilling required
c) Body Materials
| Code | Material | Typical Use |
|---|---|---|
| 1 | Bronze | Most common; suitable for water, oils, and most liquids |
| 2 | Monel | Corrosion-resistant; for seawater and aggressive media |
| 3 | 316 Stainless Steel | Chemical resistance; food-grade and high-purity applications |
Standard bellows: Bronze. Optional: Monel, 316 SS, or Inconel. Standard seals: Buna-N. Optional: Viton (A), EPR (B), Teflon (B2).
d) Flow Direction Codes
e) Full Scale Flow Rate
Specify the full-scale flow rate in GPM (liquid) or SCFM (gas). Prefix with "M" for metric units (l/min or Nm³/h). For best accuracy, select a range that places normal operation in the upper half of the scale. Use Option E for non-standard flow rates; Option ES for low-flow ranges below 2 GPM.
Standard Liquid Flow Ranges
| Pipe Size | Standard Full-Scale Ranges |
|---|---|
| ½″ | 2 GPM · 3 GPM · 4 GPM · 6 GPM · 10 GPM |
| ¾″ | 6 GPM · 10 GPM · 15 GPM · 20 GPM |
| 1″ | 15 GPM · 20 GPM · 30 GPM · 40 GPM |
| 2″ | 40 GPM · 60 GPM · 100 GPM · 150 GPM · 200 GPM |
| 8″ | Up to 3,000 GPM |
Low-Flow Option (ES)
Ranges below 2 GPM available — e.g., 4 GPH, 6 GPH, 10 GPH, 15 GPH.
Gas Flow Ranges
40 SCFH (½″) up to 20,000 SCFM (8″). Requires Option I for compressed gas service.
f) Table of Options
| Code | Description |
|---|---|
| A | Viton Seals |
| B | EPR Seals |
| B2 | Teflon Seals |
| C | Calibrated for Specific Gravity |
| D | Gasketed Case |
| D2 | Gasketed Case with Condulet |
| E | Non-Standard Flow Rate |
| ES | Low Flow Rate (Below 2 GPM) |
| F | Aluminum Housing with Plastic Dial Crystal |
| F2 | Aluminum Housing with Glass Dial Crystal |
| G | Custom Scales and Dials |
| H | High Pressure Service (400 psig max.) |
| I | Compressed Gas Service |
| J | Peak Flow Indicator |
| K | Saturated Steam Service (120 psig max.) |
| N | Ammonia Service |
| P | Panel Mount |
| R2 | Remote Readout, Brass |
| R3 | Remote Readout, 316 SS |
| T | Expanded Temperature Range |
| V | High Viscosity Service (5–500 cps) |
| W | 4–20 mA DC 4-Wire Transmitter |
| W2 | 4–20 mA DC 2-Wire Transmitter |
| W3 | 4–20 mA DC 2-Wire Output Only |
| RW3 | Digital Display Readout |
| X | Hi / Lo Alarm Relays |
| Y | 0–1000 Hz Frequency Transmitter |
| Z | Combination of W, X & Y |
Multiple options can be combined — append codes in sequence (e.g., AD = Viton seals + Gasketed case).
g) Reed Switch Options
| Code | Description |
|---|---|
| 1S2 | Single Pole Double Throw Reed Switch |
| 2S2 | Two Single Pole Double Throw Reed Switches |
Reed switches are adjustable from 30–90% of full scale. See the Limit Switches page for full specs.
Approval Suffixes
| Suffix | Description |
|---|---|
| -EM | Electromagnetic Compatibility 89/336/EEC |
| -IS | Intrinsically Safe 94/9/EC |
Installation Guidelines
Straight Pipe Upstream
Provide at least 10 pipe diameters of straight pipe between the meter inlet and any upstream fittings (elbows, tees, reducers, or valves).
Control Valves Downstream
Install control valves or solenoid valves downstream of the meter whenever possible to maintain back-pressure and ensure accurate readings.
Minimum Readable Flow
Minimum readable flow is approximately 15% of full scale. For best accuracy, select a range that places normal operation in the upper half of the scale (50–90% F.S.).
Flow Direction
Observe the flow direction arrow on the meter body. The meter is factory-configured for the specified flow direction and cannot be reversed in the field without reconfiguration.
Services Not Recommended
The Flo-Gage™ is not suitable for the following services. Contact the factory if you are unsure whether your application qualifies.
- Resins, paints, or monomers that form deposits
- Super-solvents that attack elastomers
- Sulfuric acid
- Foams with inconsistent densities
- Toxic substances requiring hermetically sealed enclosures
- Fluids above 500 centipoise viscosity
- Piston pump systems with pulsating flow
- Gravity-fed systems with insufficient pressure differential
Ready to Place Your Order?
Fill out the quote request form with your model number and application details, or call our engineering team directly. We'll confirm your configuration and provide pricing and lead time.
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