Oil flowmeter

Fluidyne oil flowmeter solutions are designed for accurate and dependable measurement across a wide range of industrial oils, from light lubricants to highly viscous furnace oils. The oscillating piston oil flowmeter uses a pressure-balanced design, helping maintain measurement stability under demanding process conditions.

With pressure compliance up to 650 bar, the oil flowmeter is equally suited to conventional process duties and high-pressure applications. Its positive displacement principle enables the oil flowmeter to perform reliably across varying viscosities and low flow rates, while the absence of metal-to-metal contact reduces wear and maintenance. This makes the Fluidyne oil flowmeter a robust choice for continuous measurement, batching, dispensing and totalization applications.

Core Information

The Oscillating piston oil flowmeter incorporates precision engineered measurement chamber and rotor assemblies.

Core Configuration

  • Precision machined measuring chamber with defined geometry
  • Single oscillating piston as the only moving element

  • Electronic transducer

  • Electronic transmitter with industrial outputs

This configuration allows the same oscillating piston positive displacement meter principle to be adapted across various products without compromising accuracy.

  • High measurement accuracy – up to ±0.1%
  • Repeatability better than 0.015%
  • Oscillating piston positive displacement technology
  • No metal-to-metal contact
  • No straight runs of pipe needed
  • Standard CF3M 316L and PTFE/FKM-A material options
  • ATEX/IECEx options for hazardous-area applications
  • Suitable for low to very high viscosity oils
  • Pressure compliance upto 650 bar with Series 6610
  • Design temperature range – -50 to 150 deg C
  • Wide flow range across ¼” to 4” sizes
  • Flow capacities up to 120 m³/hr
  • Viscosity range up to 300,000 cP
  • Low maintenance, wear-resistant construction
  • Digital flow rate and totalized volume indication
  • High-pressure configurations available
  • Suitable as furnace oil flow meter, fuel oil flow meter and lubricating oil flow meter
  • Single rotor technology for all oil variants – viscous and low viscous
  • Suitable for oil service upto 150 deg C
  • Standard 316L construction for 100% chemical compatibility
  • Excellent repeatability for consistent process control
  • Reliable measurement at low flow rates upto 3LPH
  • Pressure compliance upto 650 bar for powerpacks
  • Low maintenance
  • Minimal wear for long operating life
  • No long straight pipe runs required
  • Ideal for batching, dispensing and totalization
  • Pressure balanced design for minimal to no calibration factor drift

Applications

Hydraulic Powerpacks

  • Powerpack flow monitoring
  • Injection moulding
  • Hydraulic oil circulation

Pump Testing

  • Hydraulic pump testing
  • Positive displacement pump test rigs

Power Plants

  • Gas turbines
  • Boiler feed pumps
  • Hydraulic power units
  • Transformer oil
  • Gearbox oil

Engines

  • Marine
  • Fuel flowmeter
  • Automotive engines

Related Products

Series 6600 – Oscillating Piston Flowmeters

  • 6600 Product Catalogue

  • Instruction Manual

  • Application notes

Series 6610 – Oscillating Piston Flowmeters

  • Catalogue

  • Instruction Manual

FAQ’s

What is an oil flowmeter, and how does it work?

An oil flowmeter is an instrument used to measure the volume or flow rate of oil passing through a pipeline. Fluidyne oscillating piston flowmeters operate on the positive displacement principle, where a precision piston oscillates within the measuring chamber and displaces a fixed volume of oil during each cycle. These movements are electronically detected and converted into accurate flow rate and totalized volume.

Industrial oil measurement commonly uses positive displacement, Coriolis, turbine, gear and variable-area flowmeters. The appropriate technology depends on flow range, viscosity, pressure, accuracy and operating conditions. Positive displacement meters, particularly oscillating piston designs, are well suited to oil measurement because they directly measure displaced volume and can handle applications ranging from a lube oil flow meter to heavy and viscous oils.

Oil viscosity can vary significantly between products and with operating temperature, making it an important consideration when selecting an oil flowmeter. High-viscosity oils can increase pressure loss and affect the performance of certain flow measurement technologies. Positive displacement oscillating piston meters are particularly suitable for viscous liquids, making them an effective choice for applications such as lubricating oils, furnace oils and other heavy petroleum products.

Temperature directly influences oil viscosity and density, while pressure determines the mechanical and sealing requirements of the flowmeter. As temperature rises, oil generally becomes less viscous, which can alter flow characteristics and meter performance. A fuel oil flow meter should therefore be selected according to the application’s complete temperature, pressure, viscosity and flow range to ensure reliable measurement throughout actual operating conditions.

Selecting the right oil flowmeter requires evaluating the oil type, minimum and maximum flow rate, viscosity, operating temperature, pressure, required accuracy, pipe size and material compatibility. The application should also be considered, whether selecting a furnace oil flow meter, lube oil flow meter or fuel oil flow meter. Positive displacement meters are particularly effective where accurate volumetric measurement across varying viscosities is required.

Calibration frequency depends on measurement criticality, operating conditions, company procedures and applicable regulatory requirements. Periodic verification against a traceable standard helps identify measurement drift. Fluidyne oscillating piston meters use a piston manufactured from engineering polymers such as PEEK, eliminating metal-to-metal contact within the measuring chamber. This low-wear construction reduces routine maintenance requirements while supporting reliable long-term operation of the digital oil flow meter.