OG7 Rugged Oval Gear Flow Sensors: Summary
The rugged OG7 oval gear flow sensor (meter) is designed to give high performance with a low cost of ownership. It has a standard flow range from 5 to 500 L/min on 30 cSt oil and 20 to
500 L/min on water like liquids. The standard inlet and outlet are 2” female threads. For OEM use other alternatives, including manifold mountings, are available. The standard model is 316 St St with Viton® ‘O’ ring seal.

OG7 Rugged Oval Gear Flow Sensor
OG7 Rugged Oval Gear Flow Sensors: Features
At the heart of the OG7 oval gear flow sensor (meter) are a pair of toothed oval gears one of which contains chemically resistant magnets, the gears rotate freely on robust bearings. Rotation is detected through the chamber wall by a Hall Effect detector or a reed switch giving approximately 15 pulses per litre passed. The output is an NPN pulse or a voltage free contact closure either of which is readily interfaced with most electronic display or recording devices. This combination of materials and technology ensures a long life product with reliable, accurate operation throughout.
- Excellent chemical resistance
- Rugged construction
- Individual calibration
- High viscosity capability
- Low pressure loss
- No flow conditioning required
- Hall, reed switch or Namur sensor
- Accuracy
- 1.0 % reading water
- 0.5 % reading oil
- ±0.5% reading *
- 0.1% repeatability
- IP67/NEMA 4 protection
- * When used with our metra-smart instrument
The OG7 oval gear flow sensor (meter) is Ideal for:
- Engine test
- Oil flow
- High viscosity fluids
- OEM equipment
- Hazardous area flow sensor installation

OG7 Rugged Oval Gear Flow Sensor
OG7 Rugged Oval Gear Flow Sensors – Standard Materials of Construction
- Body and cap – 316 St St
- ‘O’ Ring – Viton®
- Gears – PEEK
- Magnets – Ceramic
OG7 Rugged Oval Gear Flow Sensor Models
Sample product codes | Stainless standard OG7-SS5-VHD-B | |
Flow range | – Water | 20 – 500 LPM |
– 30 cSt Oil | 5.0 – 500 LPM | |
Wetted materials | – Body | 316 Stainless |
– Gears | Carbon filled PEEK | |
– Seal | Viton® | |
– Magnet | Ceramic | |
Accuracy | – Water | ± 1.0 % FSD |
– 30 cSt Oil | ± 0.5% Reading | |
Repeatability | ± 0.1% | |
Detector type | Hall effect | |
Terminations | M12 Terminal cable gland | |
Approximate ‘K’ factor – Pulse/L | 15 |

OG7 Rugged Oval Gear Flow Sensorss: Flow Rate

OG7 Rugged Oval Gear Flow Meters

OG7 Oval Gear Flow Meters
OG7 Rugged Oval Gear Flow Sensors: Order Codes

OG7 Rugged Oval Gear Flow Sensor

e.g. OG7-SS5-VHD-B is a stainless steel meter
rated at 80°C, 50 Bar, Viton™ seal, Hall effect
detector and a 2” BSP thread.
‘O’ rings – OG7 Rugged Oval Gear Flow Sensors
Viton™ is the standard material for all of our flowmeters although nitrile and EPDM are available as options. Due to the vast number of differing chemicals that can be put through the flowmeter various other elastomer materials may be available for the flowmeter of your choice. Please contact your sales representative for technical help on this matter.
Magnets – OG7 Rugged Oval Gear Flow Sensors
The standard magnet material is ceramic which has very good chemical resistance in a wide range of fluids. They are attacked by some very strong acids and should be replaced with coated magnets if this is the case. The alternative coatings are PTFE and PVC depending on the meter size or the detection method, consult your representative for more information.
Gear material – OG7 Rugged Oval Gear Flow Sensors
PEEK™ is a high temperature engineering thermoplastic. It is tough, rigid and strong with very good chemical and radiation resistance. It retains its excellent mechanical and tribological properties at high temperatures. This valuable combination of properties makes PEEK™ an ideal material for our gears. The grade of material used is carbon fibre reinforced with added graphite and PTFE, these additives give extra strength and reduced friction but remain captive in the material matrix and do not compromise the chemical resistance. Alternative gear materials may be available, contact your distributor for more details.
High temperature rotors – OG7 Rugged Oval Gear Flow Sensors
Because of the high temperature characteristics of PEEK™ we can use the same material for all flowmeter temperature ranges. The standard meter is manufactured for use up to 80°C (176°F) but optional rotors are available for 100°C (212°F) and 150°C (318°F).
High viscosity rotors – OG7 Rugged Oval Gear Flow Sensors
The operation of the meter requires specially modified gears for use with high viscosity fluids, over 1000 cps. Above this viscosity the maximum flow capacity of the meter is reduced and the gears are modified. The low flow capability and the overall accuracy both improve dramatically. See the graph below for the percentage reduction in maximum flow with these thicker fluids.
Flanges and pipe connections – OG7 Rugged Oval Gear Flow Sensors
The standard products are shown on the appropriate data sheets but any meter can be manufactured with alternative fittings to suit your application, consult your distributor for details.

OG7 Rugged Oval Gear Flow Sensors – Viscosity Graph