Straight Through Sight Flow Indicator with Ball

Flow Indicators are used as a visual aid to process operations and plant protection. They provide windows into pipelines, enabling the user to see immediately if flow is taking place and to observe colour and condition of the flow. The design of the 400B dictates that it must be installed with the glass upright. The ball is subject to wear and must be changed at service intervals.


  • Compact Sight Flow Indicators are used in plant room application to show coolant or lubrication flows to pump, compressors and engines. This enables the user to view flow, presence and the condition of a liquid, gas or condensate.
  • The Fig.400B can handle a great variety of fluids, including gases and wide flow ranges.
  • The Fig.400B is easily maintained by unscrewing the glass retaining ring.
  • Available in both Gunmetal or Stainless Steel bodies giving the user greater options of flow medium.
  • The Nitrile seals provide excellent chemical resistance, further enhanced in the stainless steel version by the use of Borosilicate glass as standard.
  • When flow is present the PTFE ball rises and oscillates within the glass dome. When flow stops, the ball drops.
  • Rhodes Sight Glasses are fully manufactured in Great Britain, with castings from Great Britain
Fig. 400B Datasheet Download Installation, Operating & Maintenance

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