Rotameter R4M

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The “R4M” metallic rotameters model are normally applied in measuring liquids or gases when the process temperatures or pressures are high or in cases which opaque liquids or corrosive conditions could affect the glass tubes utilized in the common rotameters.


  • A wide range of capacities in the 3/4” to 3” sizes.
  • Simple, robust, easy to maintain.
  • Accessories available for coupling to the float extensions: electric transmitters and fIow alarms.
  • ANSI 150 PSI RF fIanges (standard), and up to 1500 PSI (optional) or others upon request, with bottom to side flow through 90°C.
  • Virtually not affected by variations in viscosity.


  • Rotameter body: manufactured in cast iron ASTM A48 CL.35, stainless steel ASTM A744 CF8 or CF8M (AISI 304 or 316), carbon steel, Alloy-20, HASTELLOY B or HASTELLOY C, among others subject to future consultation.
  • Float: ASTM A744 CF8 and CF8M, Alloy-20, HASTELLOY B and HASTELLOY C, among others subject to future consultation.
  • Gaskets: neoprene, PTFE, Viton, among others subject to future consultation.


  • Scale: nominal scale length approx. 127mm for horizontal indicator and 180mm for vertical indicator (80mm for 3/4” rotameters).
  • Graduations standard: direct to the exact service required by client. 


  • Industrial Accuracy:
    • Standard: approx. 2% of full scale, in accordance with ISA RP 2S10.
    • By request: approx. 1% off full scale, in accordance with ISA RP specifications 1S10.
    • Reproducibility: within 0,5% of full scale.
    • Rangeability: 10: 1

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