COVOL Series Volumetric Flowmeters (Oscillating Piston Positive Displacement Flowmeters)

The COVOL series consists of oscillating piston positive displacement flowmeters designed for precise measurement of the flow of any type of liquid, including highly viscous ones (up to 120,000 mPa·s). The instruments allow bidirectional flow measurement, can be installed in any position, and do not require straight pipe runs upstream or downstream.

Operating Principle

The fluid flows through an annular measuring chamber, forcing the oscillating piston to rotate and alternately fill and empty the chamber. A fixed volume of liquid is displaced with each cycle. A magnet embedded in the piston activates a reed switch sensor on each full rotation, generating a pulse signal. The electronic converter processes the signals to provide instantaneous flow rate, accumulated volume, and other parameters (4–20 mA, HART, etc.).

Key Features

• Accuracy: ±0.8% of measured value, repeatability ±0.3%.

• Flow range: 25 l/h – 60 m³/h (depending on DN10–DN100).

• Viscosity: up to 120,000 mPa·s.

• Medium temperature: from –30 °C to +150 °C (depending on materials).

• Pressure: PN16 (stainless steel), PN10 (plastics).

• Body materials: stainless steel AISI 316L, PVC, PP, PTFE; piston — PTFE+graphite, aluminum, bronze, PVDF.

• Connections: flanged (DN10–DN100), threaded, sanitary couplings (Tri-Clamp®, DIN 11851, etc.).

• Output signals: pulse (reed switch), optional 4–20 mA/HART, Modbus, relays, batching.

• Options: ATEX Ex ia/Ex d explosion-proof version, heating/cooling jacket, batching function.

• Installation: any position, mandatory filter upstream of the instrument.

Main Applications

• Chemical and petrochemical industry (measurement of aggressive and viscous liquids).

• Dosing and tank filling (including food and pharmaceutical industries).

• Condensate measurement in boiler houses.

• Burner systems, fuel and lubricant flow control.

• Processes requiring high accuracy for clean or viscous liquids without solid particles.

The COVOL series is an ideal solution for precise volumetric dosing and metering of viscous and aggressive media in industrial environments.

About TECFLUID

TECFLUID S.A. is a Spanish manufacturer (Barcelona) of measuring instruments for flow and level of liquids and gases, operating since 1974 (over 50 years of experience). The company specializes in the development and production of turbine, positive displacement (piston, gear), variable area, electromagnetic, and ultrasonic flowmeters, as well as float level gauges and converters. The products are ISO 9001, PED, and ATEX certified; they are exported worldwide and renowned for high quality and adaptation to industrial conditions.