SDM: Slurry Density Meter

After years to be successful with model 9690, Rhosonics introduces the latest generation density meter, the SDM series. This instrument is suitable for density measurement in all kinds of slurries. The product differentiates itself with its sustainable technology and its specific design for dredging and mineral processing applications.

Dredging and mining companies are increasingly looking for non-nuclear measurement equipment. A growing demand is seen for non-nuclear alternatives, because of stricter government regulations, safety related costs and the need to reduce nuclear waste. The SDM makes use of non-intrusive ultrasonic sensors to measure the density of mineral slurries. Like nuclear density gauges, the SDM is able to measure under high density levels and at very large pipes.

By measuring the acoustic impedance of a slurry, the SDM calculates the density of the slurry in-line during the process. The sensor is made of stainless steel and ceramic material. Because of the new sensor material, the sensor has lots of better properties. By making use of ceramics material, the ultrasonic signal is more brightful and powerful than before. Also, the sensor is at least as wear resistant as its predecessor, model 9690. By means of wafer cells, spool pieces or even a weld-on piece, installation is possible at very large pipe sizes like 32” and even higher.



  • Mining, Metals & Mineral Processing, Dredging, Building Materials, Energy & Power Supply, Pulp and Paper and any other industry where density measurement is required.


  • Inline density measurement

Measurement parameters:

  • Acoustic impedance

Possible sensor installations:

  • UFTC Spool
  • Weldolet
  • UWC Wafer

Sensor specifications:

  • Max pressure: 16 bar
  • Material: Ceramic and Duplex Stainless steel 1.4462
  • Process connection: DIN/ANSI/JIS and others on request
  • Process temperature range: 0 °C … 110 °C (32 °F... 230 °F)
  • Wetted parts: Ceramic and Duplex Stainless steel 1.4462

Readout and Housing:

  • Protection: IP68, NEMA 6P
  • Monochrome display with RGB backlight, behind glass cover
  • Main screen with following characters;
  • Readings: SG, Density g/l


  • Power supply: 18 … 32 VDC, 8 Watt
  • Communication: HART 4-20mA (1x)

Measurement specifications:

  • Accuracy: up to 0.005 (S.G.)
  • Decay time: < 1 to 99 s (adjustable)

Get in touch with Rhosonics for further information about the SDM slurry density meter.

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