Magnetic vs Coriolis vs Vortex Flow Meter: Which One Should You Use?
Magnetic, Coriolis and vortex meters can all measure flow, but they solve different engineering problems. A magnetic flowmeter is primarily a volumetric-flow solution for conductive liquids. A Coriolis meter directly measures mass flow and can also provide density and temperature information. A vortex meter is a versatile volumetric-flow technology for liquids, gases and steam when the process and installation conditions are suitable. Selecting between them should begin with the phase and properties of the medium, followed by the measurement objective, flow range, pressure and temperature, accuracy requirement, pressure-drop tolerance and installation constraints.
FLOW TECHNOLOGY
Quick comparisonHow each worksHead to headBy mediumWhat to collect
Not Sure Which Flow Technology You Need?
01 QUICK COMPARISON
Magnetic vs Coriolis vs Vortex
| FACTOR | Magnetic | Coriolis | Vortex |
|---|---|---|---|
| Liquids | Yes — conductive liquids | Yes | Yes |
| Gases | No | Yes | Yes |
| Steam | No | Not the normal Yokogawa selection | Yes |
| Conductivity required | Yes | No | No |
| Direct mass flow | No | Yes | No — normally volumetric unless compensated externally |
| Density / concentration | No direct density measurement | Yes, model/application dependent | No direct density measurement |
| Typical Yokogawa family accuracy | AXG ±0.3% of rate standard; AXW ±0.35% | ROTAMASS up to ±0.1% of rate at family level | Vortex family figures around ±0.75% of rate for applicable liquid service |
| Strong applications | Water, wastewater, chemicals, conductive slurries | Batching, dosing, mass balance, density/concentration | Steam, gas, plant utilities |
The accuracy figures above are product-family reference values from Yokogawa’s general flowmeter comparison and should not be used as a final guarantee for every model or process. The General Specification for the selected meter and the actual fluid and flow range must be checked during engineering.
02 / MEASUREMENT PRINCIPLES
01
How Magnetic Flowmeters Work
Magnetic flowmeters apply a magnetic field across a pipe and measure the voltage generated by a conductive liquid moving through that field. The result is volumetric flow. There are no mechanical moving parts in the measurement path, and the full-bore design can be attractive for water, wastewater, corrosive liquids and many slurry services. The main limitation is fundamental: the liquid must be sufficiently conductive for the selected meter. Magnetic meters do not measure gas or steam, and they do not directly provide mass flow or fluid density.
Within the Yokogawa portfolio, ADMAG AXG is positioned strongly for process-industry applications and covers sizes from 2.5 to 500 mm with ceramic and PFA liner options. AXW extends to 1,800 mm and is strongly positioned for general industrial, water and sewage duties with PTFE and rubber-based liners. If magnetic technology is already the correct measurement principle, Tomarok’s ADMAG AXG product page and magnetic flow meter selection guide can be used for the next level of model selection.
02
How Coriolis Flowmeters Work
A Coriolis meter measures the effect created as the process fluid moves through vibrating measurement tubes. This allows direct mass-flow measurement rather than calculating mass from a separate volumetric flow and density value. Yokogawa’s ROTAMASS Coriolis portfolio can also provide density and temperature information, which makes the technology attractive for batching, blending, filling, dosing, mass balance, chemical recovery and concentration-related applications. Tomarok’s Rotamass Prime page represents one existing commercial route into this product family.
Coriolis is not automatically the best option whenever accuracy is important. Meter size, pressure drop, fluid density, viscosity, gas fraction, installation and capital cost all matter. The technology is especially valuable where mass is the actual process objective or where density information eliminates another measurement. Yokogawa’s general flowmeter comparison positions Coriolis for liquids and gases, but not as the normal selection for steam service.
03
How Vortex Flowmeters Work
A vortex meter places a bluff body in the flowing stream. As the fluid passes the body, vortices are shed at a frequency related to flow velocity. Vortex technology can be used for suitable liquids, gases and steam, which is why it is common in plant-utility measurement. Yokogawa has a long history in industrial vortex measurement, and Tomarok’s Yokogawa vortex flowmeters category provides the commercial route for this technology.
Vortex meters need a suitable Reynolds number and flow profile. Very low flow, severe vibration, two-phase flow and poor upstream piping can reduce performance. Straight-run requirements and actual min/normal/max flow should therefore be checked during sizing. For steam applications, pressure and temperature are important because mass or energy calculations may require compensation beyond the basic volumetric-flow measurement.
Magnetic vs Coriolis
Choose between magnetic and Coriolis by asking whether the liquid is conductive and whether the process needs volume or mass. For conductive water, wastewater or a compatible slurry, magnetic measurement can provide a simple full-bore volumetric solution with low permanent pressure loss. For dosing, mass balance, density or concentration measurement, Coriolis can provide more process information directly. If the liquid is non-conductive, magnetic technology is eliminated regardless of other advantages.
Magnetic vs Vortex
Magnetic and vortex meters overlap mainly in liquid applications. Magnetic technology is particularly strong for conductive liquids, including many dirty or solids-bearing streams. Vortex can measure both conductive and non-conductive suitable liquids and also extends to gases and steam. The trade-off is that vortex requires a flow profile and Reynolds number suitable for vortex generation, while magnetic measurement depends on liquid conductivity and a full pipe.
Coriolis vs Vortex
Coriolis is the stronger starting point when direct mass flow, density or concentration is required. Vortex is often the more natural technology for steam and plant-utility gases. For liquid or gas services where both could be considered, the decision should compare required accuracy, turndown, pressure drop, line size, process conditions, installation constraints and whether density information adds real value to the process.
04 BY MEDIUM
Flow Meter Selection by Medium
| PROCESS MEDIUM / OBJECTIVE | Recommended starting technology |
|---|---|
| Conductive water / wastewater | Magnetic |
| Conductive corrosive liquid | Magnetic, subject to liner/electrode compatibility |
| Conductive slurry | Magnetic, subject to solids/abrasion/application review |
| Non-conductive liquid requiring mass flow | Coriolis |
| Batching / dosing by mass | Coriolis |
| Density / concentration required | Coriolis |
| Saturated or superheated steam | Vortex or engineered DP solution |
| Compressed air / suitable process gas | Vortex or Coriolis depending on objective |
| Plant utility liquid where conductivity is suitable | Magnetic or vortex depending on application |
05 CHECKLIST
What Information Should Be Collected Before Selecting a Flowmeter?
- Fluid phase: liquid, gas or steam
- Full chemical composition and conductivity for liquid service
- Density, viscosity and solids content where relevant
- Min/normal/max flow
- Pipe diameter and schedule
- Operating and design pressure
- Operating and design temperature
- Required volumetric or mass flow output
- Need for density, concentration or energy calculation
- Required accuracy and turndown
- Allowable pressure drop
- Available straight pipe and installation orientation
- Hazardous-area classification
- Output signal and communication protocol
- Cleaning, hygiene, abrasion or corrosion requirements
Request a Yokogawa Flowmeter Recommendation
If you are deciding between magnetic, Coriolis and vortex measurement, send Tomarok the process medium, min/normal/max flow, pipe size, pressure, temperature, conductivity for liquids, density or viscosity if known, required output and installation constraints. The first goal is to select the correct measurement principle. Once that decision is made, the enquiry can be directed to ADMAG AXG, ROTAMASS Coriolis or Yokogawa vortex flowmeters and then narrowed to the appropriate model and option code.
