Customer pain point
Low-velocity gas in a large duct can leave a conventional insertion probe with too little usable DP—or make a full-bore restriction impractical.
Custom low-loss measurement for large gas ducts
Double-Venturi Gas Flowmeters — Custom Large-Duct Gas Flow Meter
Application-engineered internal and insertion differential-pressure assemblies for low-velocity gas in large circular and rectangular ducts.
Rectangular-Duct Double-Venturi Flowmeter
Image 1 of 4 · Auto-advances every 3.2 seconds
MANUFACTURER-SPECIFIC LARGE-DUCT METERING
Not a classical Venturi—engineered for low-velocity gas
The Shizhong Double-Venturi is a custom differential-pressure sensing assembly for large circular and rectangular gas ducts. It is selected when low gas density, weak signal, limited allowable pressure loss and retrofit access must be solved as one measurement-system problem.
Shizhong engineering response
Internal, insertion and integrated assemblies are configured around the actual section, process density, disturbance layout, access and maintenance plan.
Defensible performance
Coefficient, usable range, loss and uncertainty are stated from the approved geometry plus representative calibration or site correlation.
Configuration routes
Round or rectangular · internal or insertion
A factory-built measurement section controls supports and alignment. An insertion arrangement can reduce retrofit scope. Rectangular ducts require measured clear dimensions and a profile-validation plan.
Standards boundary
No transferred ISO 5167-4 coefficient
This device is not the classical Venturi tube defined by ISO 5167-4. ISO 3966, ISO 16911 and ISO 14164 may support reference measurement and validation where applicable; they do not assign one universal coefficient, accuracy or straight run to this product family.
Large-duct gas measurement engineered around the actual installation
Shizhong Double-Venturi Gas Flowmeters address large-duct duties where low gas density, low velocity, limited pressure-loss allowance and restricted retrofit access must be solved together. The manufacturer-specific sensing geometry produces a usable differential-pressure signal without the size and process penalty of a conventional full-bore restriction. Internal, insertion, integrated round-duct and rectangular-duct configurations are engineered around the actual process, duct, disturbance layout, maintenance plan and validation objective. This product is not the classical Venturi tube defined by ISO 5167-4; its coefficient and performance belong to the approved Shizhong geometry and project evidence basis.
Key design features
More usable differential-pressure signal for low-velocity gas
Low-loss internal or insertion configurations for large ducts
Round and rectangular duct engineering
Project-specific calibration, velocity-area comparison or site correlation
Related Solutions
Power GenerationEngineered DP measurement for main and auxiliary steam, feedwater, cooling water, combustion air and flue-gas duties in power and boiler systems.MetallurgyRugged flow measurement for blast-furnace and coke-oven gas, combustion air, cooling water, oxygen-service utilities and severe steelmaking processes.Chemical & PetrochemicalApplication-specific DP primary elements for corrosive, viscous, crystallizing, solids-bearing and variable process streams, with materials and maintainability considered from the start.
Typical applications
01
Blast-furnace, coke-oven, converter and mixed-gas ducts
02
Boiler primary air, secondary air and combustion air
03
Flue gas and large process-exhaust ducts
04
Low-pressure, low-velocity industrial gas measurement
Final specifications are confirmed against process data, piping, material, pressure class, applicable code and metrology requirements.
Related products
Full-Section Matrix FlowmetersA patented multi-point differential-pressure array engineered for large circular pipes, rectangular ducts and gas-flow profiles that a single-point or single-bar probe may not represent.Lierba & Averaging Pitot FlowmetersShizhong Lierba™ combines a low-loss insertion probe with a proprietary anti-plugging pressure-opening concept, drainage-friendly geometry and engineered purge or online-service options for large pipes and difficult gases.
Need full specifications?
Request a detailed datasheet with dimensional drawings, material certificates and ordering information for Double-Venturi Gas Flowmeters.
Production and documentation schedules are confirmed in the quotation after technical review and drawing approval.
Ready to discuss your application?
Send your process data for an engineering review and a project-specific next step.
ISO 9001TS Licensed30+ PatentsSince 1989