Tailor-made solutions for industrial steam, gas and liquid flow metering

 Deltaflow on Tube
 The Deltaflow itself

DELTAFLOW - averaging pitot tube for flow metering of steam, gas and liquids


A number of patents and several decades of continious product development make the deltaflow to a leading flow meter in process industries. The result is a flow which is optimized on measurement accuracy and excellent process stability with a minimized pressure loss. Our robust and reliable devices are even suitable for diry gases duch as humid biogas, oily compressed air or hightemperature and highpressure steam. The prinziple of operation, the Pitot Principle is well known and documented in the ISO 5167. Compared with classical primary elem,ents such as orifice, venturi or nozzle, the deltaflow has a number of advantage:


- Minimal pressure loss. In particular for steam or compressed air applicatiopns, might might save several kW
- simple installation
- light weight and easy to handle, even on big tubes
- highest measurement accuracy (up to 0,4%)
- not sensitive to dirt or condensates, flow metering in oily compressed air, humid bio gas or dirty stack gas is possible.
- low acquisition cost
- proven calculation basics that use the same formulas as primary elements (orifice, venturi, nozzle), so binding the deltaflow in a DCS works without any trouble
Steam meter

 deltaflow flow meter is an ecologic wonder:

The systec Controls deltaflow flow meters are in use for more than ten thousand times. Some application possibilities is the measurement of amounts of steam, biogas flow measurement or measuring any other gas.

By thinking about the deltaflow in use with steam can save serveral kW of Energy compared with an aperture, you may notice very fast that you don't save money only, you also protect our enviroment.

deltaflow_brochure_en.pdf [1.83 MB]
deltaflow product information

deltaflow_installation_guide_english_revision122012_1.pdf [1.17 MB]
deltaflow installation guide

deltaflow_ptb-report_e.pdf [1.17 MB]
deltaflow ptb report


Precision and Process Viability of the deltaflow Integrating Pitot Tube

Approximately 30% of all flow measurements in plant installations are based on the principle of differential pressure. In spite of the high level of pressure loss and the energy waste associated with it, as well as the installation difficulties in comparison to dynamic pressure probes, most measurements in this area are still made using orifices.
Constant pressure lost by dynamic pressure probes is significantly less than that lost by apertures; nevertheless, these differential pressure monitors are still rather rare in current installations. Rising energy costs, increasingly stringent environmental codes, and the steadily increasing pressure of competition all force modern industry into a process of continually increasing operational efficiency. Today, new coalfueled power stations reach an efficiency rate of up to 46%; many gas-fueled power plants report an efficiency rate of over 58%. Flow sensor technology often lags behind this development.
In the past, poor levels of precision and insufficient process viability have generally limited the application of dynamic pressure probes to “non-critical” metering sites which required less exact measurement. Insufficient documentation and the lack of reliable calibration data and up-to-date project management aids made it even more impractical to successfully install dynamic pressure probes.
Since its founding, systec Controls GmbH of Puchheim (Germany) has invested an enormous amount of resources in the effort to address these difficulties. They have performed their own research, and they have enlisted independent third parties in the effort. Naturally, this effort includes developing solid and well-established technical material, user-friendly documentation, and state-of-the-art project management aids.

Measurement Principles of the deltaflow Dynamic Pressure Probe

The deltaflow series of dynamic pressure probes represents the result of all of this work. The deltaflow’s high level of precision and excellent process viability—even in
extreme conditions—proves that it is superior to orifices. Similar to the Prandtl measurement tube, the deltaflow measures flow according to the differential pressure principle. In the dual chamber profile, differential pressure tapings in the flow direction and counter the flow direction result in a differential pressure between the two measurement chambers, which provides a measurement for the flow rate of the medium. Unlike the Prandtl measurement tube, the median of the flow profile is not achieved by adjusting the measurement head and the resulting average calculation. It is achieved by the advantageous positioning of multiple differential pressure tapings across the cross-section of the pipe. The following formula calculates the resulting differential pressure:

dp=u²*0.5* ζ*ρ

ζ is the probe-specific resistance coefficient which is normally determined experimentally. ρ is the density of the medium, dp is the differential pressure, and u represents the median flow rate. The influence of the process conditions ζ=ƒ(Re) on this resistance coefficient describes the error of the dynamic pressure probe.

The deltafliw integrating pitot tube was found, to have the smallest possible error on the resistance coefficient possible.