Inline Process Refractometer PIOX R721 – Hygienic Design Variant

In many processes of the food and beverages as well as in the pharmaceutical industries real-time inline concentration measurement is the key to continuous quality control and efficient production. With its process refractometer PIOX R721, FLEXIM offers for this purpose the most powerful measuring instrument of its kind.

Whether the degree of ° Brix needs to be monitored during soft and fruit drink production or concentration levels of ascorbic and cetogulon acid during Vitamin C manufacturing have to be supervised, PIOX R721 outputs the desired values with an accuracy of 0.1%.

PIOX R721 is highly hygienic by itself. With its stainless steel housing, the sapphire prism and completely engineered with no allowance for dead spaces, potential bacterial contamination can be ruled out at any time.

PIOX R721 can be integrated into the process via Varivent or Tri-clamp compatible flanges.
Process Refractometer for Hygienic Environments - PIOX R - Hygienic Design Variant


  • Highly accurate, reliable and hygienic real-time concentration measurement solution (sugar content, ° Brix,  and more)
  • No measurement drift due to potential plate out as often indicated when employing conventional critical angle refractometers
  • Quality assurance due to real time product monitoring - costly laboratory testing becomes obsolete

Technical Facts

Measuring quantities
Refractive index and refractive index at standard temperature, fluid temperature, concentration g/l, mass and vol.%, density and density at standard temperature, scale values for example °Brix and °API, additional quantities programmable
Measurement range
nD: 1.3 ...1.7, °Brix: 0 ...100
Measurement accuracy
nD: 0.0002 (corresponds to: 0.1 °Brix, 0.1 w%)
nD: 0.00002 (corresponds to: 0.01 °Brix, 0.01 w%)
Operating temp. (media)
-20 °C ... (+130 °C) +150 °C
Fluid pressure
PN 10, PN 16, on request PN 40 (depending on process connection)
Degree of protection
Sensor R500: IP67, ATEX (IECEx) zone 0,/1
Transmitter R721: aluminium or stainless steel enclosure, IP66, ATEX (IECEx) zone 2
Wetted parts, materials
Stainless Steel 316L (1.4404)
Housing material
Stainless Steel 304 (1.4301)
Process connection
Compatible to Varivent or Tri-clamp connection

360° view


For the manual 360° view pull the image left or right


PIOX R721 - Process Analytics by Inline Refractometry


PIOX R721/R500 -hygiene-

Technical Specification
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