Flow meter calibration bench

gas flow

Short description
Gas flow meter calibration devices are specialized equipment used to calibrate and verify various gas flow meters. By providing precise, known flow references, they ensure the accuracy and reliability of measured flow meter readings and are standard equipment in flow measurement.

Operating principles

• Standard Meter Method: Continuously pass gas through a high-precision standard flowmeter and the test flowmeter over identical time intervals; determine test performance by comparing outputs.
• Soap Film Method: Gas moves a soap film at constant velocity in a graduated glass tube; flow rate calculated from the time for the film to traverse a fixed volume; suitable for very low flows with high accuracy.
• Orifice Plate Method: Gas through a standard orifice creates a pressure differential related mathematically to flow rate; flow derived from measured pressure difference.
• Wet Bubble Method: Gas introduced into calibrated liquid forms bubbles detected by a photoelectric sensor; time between bubbles and tube geometry used to calculate flow.
• Integrated Calibrators: Combine technologies (e.g., differential pressure and thermal mass techniques) to cover broader flow ranges and different media.

Product Advantages and Features

• High accuracy and reliability: Standard meter-based devices can reach expanded uncertainty better than 0.5%. Soap film devices offer high accuracy and excellent repeatability for Class I precision. Wet bubble calibrators can achieve calibration accuracy of ±1% with repeatability ≤0.3%.
• Intelligence and automation: Many units provide automatic measurement, data storage and output. Examples include automatic film formation with infrared sensing and microprocessor-based processing; computerized measurement/control supports automatic flow regulation and automated verification in standard meter methods.
• Portability and field applicability: Compact designs with built-in rechargeable batteries enable field use (examples: GH-2032 portable gas flow calibrator; Laoying 7020A multi-range orifice calibrator).
• Wide range and multi-medium compatibility: Multi-range designs or combined principles cover extensive flows (examples: portable integrated units 0.1 L/min to 1200 L/min; RC-7022 portable integrated flow calibrator gas range 0–1000 m³/h; some units calibrate both gases and liquids).
• Compliance with standards: Designed and manufactured to national verification regulations and industry standards (examples: JJG586-2006, JJG640-2016, HJ/T 368-2007), ensuring authoritative verification results.

Primary application areas

• Trade settlement: mandatory verification of gas flow meters used in commercial handovers (e.g., pipeline projects).
• Environmental monitoring & industrial hygiene: calibrating flow rates for air samplers, fume samplers, dust detectors to ensure valid sampled volumes for PM2.5/PM10 and other pollutants.
• Industrial process control: regular calibration in chemical, power and other industries to avoid formulation errors, energy waste, or safety incidents.
• Metrological verification and third-party testing: used by metrology institutes and inspection agencies for traceability and value transfer across verification hierarchies.
• Research and laboratory development: high-precision calibration systems for validating instruments or providing reference standards in experiments requiring precise gas flow control.

Selection considerations
When selecting a device, consider required flow range, required accuracy, usage scenario (laboratory or field), multi-medium capability (gas and/or liquid), automation needs, portability, and budget.