The oval gear flowmeter is a high-precision volumetric flow measurement instrument, also commonly known as the "Oval Gear Flowmeter". It measures the flow by periodically rotating a pair of meshing oval gears driven by fluid pressure, dividing the fluid into fixed volume units for measurement.

• Elliptical gears: Usually made of stainless steel (316L), cast steel or Hastelloy, they are suitable for different corrosive media and pressure requirements. High-precision models have a hard alloy coating on the surface to reduce wear.
• Sealing coupling: Transmits the rotation of the gears to the counter, supporting mechanical pointer display or electronic signal output (such as 4-20mA, RS485).
• Temperature compensation module: Some intelligent products integrate this module to correct the influence of temperature changes on the volume of the medium.

• High Precision: Typical accuracy can reach ±0.5%, and some high-end models can achieve ±0.2%, suitable for trade settlement.
• High Viscosity Adaptability: The higher the medium viscosity, the smaller the gear gap leakage, and the lower the measurement error. The measurable viscosity range is 0.3 to 8 mPa・s (standard type), and special models can reach 200 mPa・s.
• Direct Reading, No External Energy Required: The mechanical dial can directly display the cumulative flow without the need for power supply to operate (very convenient for local indication).
• Unaffected by Flow State: The measurement principle is volumetric, insensitive to the flow velocity distribution at the inlet, and does not require long straight pipe sections before and after.
• Wide Range Ratio: The range ratio (the ratio of maximum flow to minimum flow) is relatively wide, typically reaching 10:1.

• Diameter: DN10 to DN150mm. Small diameter models (such as 4mm) are suitable for micro-liquid control.
• Pressure rating: Cast iron type 1.0 to 1.6MPa, cast steel type up to 6.4MPa, and high-pressure type up to 9.6MPa.
• Temperature range: -20℃ to +100℃ (standard type), high-temperature type requires special heat dissipation design.
• Output signal: Mechanical counter, pulse output, 4-20mA analog signal and Modbus/HART communication protocol.

Due to its characteristics, the elliptical gear flowmeter is often used in the following fields:

• Petrochemical industry: Precise measurement of crude oil, heavy oil, diesel, lubricating oil, and asphalt.
• Food and pharmaceutical industry: Syrup, honey, chocolate, edible oil, dairy products, and additives.
• Chemical industry: Resin, solvents, polymers, and chemical raw materials.
• Shipbuilding: Measurement of fuel consumption.
• Others: Any high-viscosity scenarios that require high-precision volume measurement and have clean media.

The elliptical gear flowmeter is a classic volumetric flowmeter that achieves high-precision measurement through mechanical means. It plays an irreplaceable role in the volume trade settlement and process control of high-viscosity, clean fluids. Despite its strict requirements for fluid cleanliness and the existence of pressure loss, its outstanding accuracy and viscosity-insensitive characteristics ensure its continued importance in specific industrial fields.