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Ultrasonic flow & Concentration

Sulphuric Acid Mass Flow, Concentration & Density Meter

Non-invasive Mass Flow, Concentration and Density Measurement of strong Sulphuric Acid and Oleum

By measuring non-invasively from the pipe wall outside and never being in direct contact with the medium flowing inside, PIOX S721 SA  is the ideal solution for monitoring strong sulphuric acid and oleum:

  • The system measures sulfuric acid concentration and mass flow directly on the main production lines (concentration range of 80% to 100%)
  • It accurately determines the acid strength in real time
  • It significantly increases plant safety and availability as it does not require any pipe opening or welding for installation nor any additional flanges
  • The measurement is free of wear or abrasion and thus also virtually maintenance free
  • It can never be a source for potential leaks and sub-sequent process shut-downs


  • Extreme reliability due to no direct contact with the medium
  • Highest accuracy over a wide flow, concentration and temperature range (up to 400 °C)
  • Increased plant safety and availability – no pipe works or process shut-downs required
  • Certified for usage in hazardous areas (ATEX, IECEX Zone 1/2 and FM Class I, Div. 1/2 certified)

Product Description


Measurement uncertainty                ±1 % of reading ±0.005 m/s
(volumetric flow rate) :

Repeatability:                                      0.15 % of reading ±0.005 m/s

Flow:                                                     velocity range0.01…25 m/s

Ex zone transmitter:                          only safe area

Power supply:                                     100-230VAC, 24DC, 12DC

Available transducer:                        Shear wave

for Ex zones:                                       —

for pipe sizes range:                          DN25 … DN2000

for temperature range:                    -40°C … +130°C

Outputs:                                              4-20mA active/passive
4-20mA HART active/passive

Inputs:                                                1x Pt100/Pt1000
1x 4-20mA active/passive

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