Based on its structure and design features,
Gear flow meterThere are mainly the following common types:
Round Gear/Spur Gear Flow Meter
Structure: Use two identical circular spur gears with standard involute teeth to mesh with each other.
Features:
The structure is relatively simple, and processing and maintenance are relatively easy.
Usually, the pressure loss is relatively small.
High precision, suitable for measuring various cleaning liquids.
Widely used for measuring fluids with low to medium viscosity, such as lubricating oil, hydraulic oil, diesel, gasoline, solvents, food grade liquids (such as syrup, juice), etc.
Application: Chemical, food and beverage, pharmaceutical, light industry and other industries.
Oval Gear Flow Meter
Structure: This is one of the classic and most common volumetric flow meters. It uses two special elliptical gears (also known as "8" - shaped or peanut shaped gears) to mesh with each other.
Features:
During the meshing process, two elliptical gears can form four (or more) independent, fixed volume measuring chambers.
The adaptability to high viscosity fluids is very good, the higher the viscosity, the smaller the leakage, and the measurement may be more accurate.
The measurement accuracy is usually very high and the stability is good.
The structure is relatively complex and requires high manufacturing accuracy.
Compared to circular gears, the pressure loss may be slightly greater.
Application: Especially suitable for measuring high viscosity liquids such as heavy oil, asphalt, resin, paint, etc. Widely used in industries such as petroleum, chemical, and shipbuilding.
Roots Meter/Rotary Piston Meter
Structure: Although sometimes broadly classified as a gear flowmeter, its rotor shape is more unique. It uses two rotors (waist wheels) in the shape of an "8" or similar "Chevrolet" logo, driven by synchronous gears (usually externally), to achieve contactless rotation.
Features:
The measuring chamber has a large volume and good flow capacity.
The disturbance to the fluid is small, and the pressure loss is relatively low.
Can measure fluids containing small amounts of tiny particles (depending on design and filtration).
Usually used in high flow, medium to high viscosity applications.
Application: Commonly used for trade settlement in the petroleum and chemical industries, as well as for measuring large storage tanks.
Spiral Flow Meter/Twin Screw Flow Meter
Structure: Use two or more rotors with helical teeth (similar to the rotors of a screw pump) to mesh and rotate with each other.
Features:
The fluid flows smoothly along the axial direction with very little vibration and noise.
The pressure loss is extremely low.
Suitable for measuring liquids with high viscosity and good lubricity.
The shear effect on the fluid is small.
Application: Mainly used for high-precision measurement of high viscosity oil products, such as lubricating oil, fuel oil, etc., especially in situations where low noise and low pulsation are required.
Internal Gear Flow Meter
Structure: Composed of an internal gear (external teeth) and an external gear (internal teeth), both installed eccentrically. The internal gear drives the external gear to rotate.
Features:
Compact structure, usually with only one rotating component (internal gear).
It can be designed to be very compact and suitable for measuring small flow rates.
Commonly used in industries such as food and medicine that require high hygiene standards.
Applications: food and beverage (such as essence, additive metering), pharmacy, laboratory equipment, etc.
Summary:
The choice of gear flowmeter mainly depends on the properties of the measured fluid (viscosity, cleanliness, corrosiveness), flow range, accuracy requirements, pressure loss requirements, and installation and maintenance conditions. Among them, elliptical gear flowmeter and circular gear flowmeter are two widely used types.