Application for Rheotherm and RheoVac Instruments
RheoVac® Multisensor Flow Monitors

RheoVac® DR Drying Monitor

The RheoVac DR is a monitoring system that eliminates the guesswork involved with vacuum drying operations. It monitors several parameters in the vacuum chamber exhaust line, before the vacuum pump or ejector, to provide a real-time, detailed measurement of the mass flow rate of the water vapor being removed from the drying process. This view of the process can be used to chart the drying cycle, make informed decisions about changes to the process and quickly evaluate the impact of these changes. One chemical manufacturer reported reductions of approximately $2,000,000 in operating costs over a four-year period. Click here to read more about these impressive results (PDF).

RheoVac® DR Vacuum Drying Monitor

What Are the Benefits?

  • Decreased drying time – Cycles can be reduced by as much as 40%
  • Increased capacity and throughput – Production bottlenecks created by the drying process are reduced.
  • Improved product integrity – Elimination of off-line sampling reduces risk of product contamination.
  • Reduced costs – Closer control and shorter cycles reduce energy consumption and maximize yield.
  • Tighter process control – Multiple process variables are monitored simultaneously.

How Do They Work?

The RheoVac DR uses a dual probe flow measurement along with three other primary process measurements to determine when dry conditions are met.

Output data includes:

  • Water vapor flow: the rate at which moisture is being removed during the drying cycle.
  • Pressure: the level of vacuum actually being achieved in the dryer.
  • Total mass flow and actual volumetric flow:  actual operating effectiveness of the vacuum equipment to remove gas and water vapor in comparison with the vacuum equipment’s performance curves.
  • Relative saturation: an output that shows the percent moisture content in the vacuum line.
  • Temperature: accurate, real-time display of the process temperature.

Typical vacuum drying process installation

How Do I Get One?

Submit your inquiry today using the on-page form to send us the application data to review, or visit our contact us page for telephone, fax and email information.

  • Provides direct reading of water vapor flow
  • Measure vacuum level and quality
  • Quantify vacuum equipment capacity and performance
  • On-board sensor diagnostics
  • Real time data is stored locally and can be routed to DCS
  Temperature   Probe: 40° – 160 °F
  Electronics: 40° – 120 °F
  Pressure   0 – 29” HgA
  Calibration    Accuracy   ± 5% of total mass flow
  Repeatability   ± 0.5% of reading
  Line Sizes   3” minimum
  Process  Connection   1” MNPT and ½” NPT
  Wetted  Material   316 Stainless steel probe; Engineered plastic probe tip
  Display   Backlit LCD
  Enclosure   NEMA 4
  Outputs   Local display, Ethernet 10Base-T, RS-422/232,and 4-20mA (optional)
  Input Power   100 – 250 VAC; 50 – 60 Hz
pdf (1) Product Brochure
pdf (1) RheoVac DR Product Manual
word RheoVac DR Application Data Sheet
(download document)
Request More Information

Required fields are indicated with an ‘*’Name*






Product Being Manufactured*

Water or Solvent based?


Dryer Type

Vacuum Line Size/Schedule*

Vacuum Line Max Temp*

Min/Max Vacuum Pressure*

Product In Line* YN


No. of Exhausters/Chambers*

Exhauster Type*

Purge Gas (if any)*

Describe problem/concerns