An oval gear flowmeter is a type of positive displacement meter that uses two oval-shaped, intermeshing gears to measure liquid flow. As fluid enters the meter, it forces the gears to rotate by filling the crescent-shaped chambers formed between the gear teeth and the meter housing. Each complete rotation of the gear pair displaces a precisely defined volume of liquid. A sensor detects the gear rotation and converts it into a flow rate or totalized volume reading. Oval gear meters are highly regarded for their accuracy, repeatability, and ability to handle high-viscosity fluids.
Oval gear flowmeters are exceptionally well-suited for oil measurement applications across a wide range of industries. They perform reliably with heavy fuel oil, lubricating oil, hydraulic oil, crude oil, vegetable oil, and other viscous fluids. Unlike turbine or electromagnetic meters, oval gear meters do not require a minimum conductivity or velocity threshold to operate accurately—they work effectively even at low flow rates. Their robust construction, typically in stainless steel, cast iron, or aluminum, ensures long service life even in demanding environments with variable pressures and temperatures.
One key advantage of oval gear flowmeters is their relatively low sensitivity to upstream flow conditions, meaning they can be installed close to bends or valves without significantly affecting accuracy. However, they should be protected by a strainer upstream to prevent solid particles from jamaging the precision gear surfaces. Regular lubrication and inspection of gear bearings, seals, and the register mechanism are important maintenance tasks. Oval gear meters are available in a wide range of sizes and materials to accommodate different pipe diameters, flow rates, and fluid chemistries, making them a versatile and dependable choice for oil flow measurement.