Double Spiral Rotor Flow Meter

Double Spiral Rotor Flow Meter is an advanced positive displacement flow meter with features of high measurement accuracy, smooth running, no pulsation, low noise, long service life, strong adaptability to various viscosities and without requirement to the upstream and downstream straight pipe length. It is widely used in many industries such as petroleum, chemical, metallurgy, thermal power, shipbuilding, and food etc. It is especially suitable for trading measurement for crude oil, highly condensed oil, crude oil with water, petroleum products, as well as engineering measurement. The flow meter can be equipped with photo-electric pulse converter or electronic flow transmitter to output pulse signal or analog current signal for remote monitoring in the control room.

Product Description

Double Spiral Rotor Flow Meter’s Principles of Measurement


The measuring chamber consists of interior case, Bi-Rotor and the top & bottom cover plates. This structure forms some volumetric-known cavities, which are the volume measuring unit of the flow meter. The pressure difference between the flow meter’s inlet and outlet (even if the tiny pressure difference) will drive the Bi-rotor to rotate, which continually transfer the liquid from the flow meter’s inlet to the outlet to implement volume flow measurement (see diagram Flow in -> Measuring -> Flow out ). The rotors’ rotating number will be transmitted to the counter by the sealed coupling and the driving system, so the total volume flow of the passing liquid can be indicated directly.


Main technical data
Size DN8 ~ 400
Accuracy 0.1%,  0.2%,  0.5%
Pressure loss < 80 Kpa ( 0 ~ 1000 cp),  < 150 Kpa (1000 ~ 20000 cp )
Pressure rating 1.6 Mpa,  2.5Mpa,  4.0Mpa,  6.3Mpa
Temperature range -20 ~ 80℃, 80 ~ 150℃, 150 ~ 250℃, -40 ~ 120℃
Medium viscosity 0 – 20000 cp
Ambient temperature -30 ~ 70℃
Process connection Flange
Pulse converter / Current converter Power supply: 12 ~ 24VDC, Explosion-proof: Exd II CT6, Weather-proof: IP65


Comparison of Double Spiral Rotor Flow Meter and Oval Gear Flow Meter

  1. Oval Gear Flow Meter has two rotors, one rotor is driving rotor, another rotor is driven by the driving rotor, it inevitably produces collision and friction, which will affect the Oval Gear Flow Meter’s service life, and with the extension of the using time, the accuracy will also be affected. Both the Double Spiral Rotor Flow Meter’s two rotors are self-driven rotors, which overcome the shortcomings of Oval Gear Flow Meter’s rotor friction. The two rotors of Double Spiral Rotor Flow Meter are the point meshing, in the process of using, there is no noise, no friction, almost no abrasion after long time using, so as to ensure its service life and measurement accuracy, and reduce the amount of maintenance.
  2. Double Spiral Rotor Flow Meter only has two clearance surfaces, Oval Gear Flow Meter( with two rotors) has 8 clearance surfaces. When measuring the medium of the same viscosity, the accuracy of Double Spiral Rotor Flow Meter is higher than that of Oval Gear Flow Meter.
  3. Oval Gear Flow Meter’s flow field has pulsation flow, while Double Spiral Rotor Flow Meter’s flow field is more smooth, which is determined by the respective measurement principle. Of course, the price of Double Spiral Rotor Flow Meter is higher than that of Oval Gear Flow Meter.
  4. From the technical point of view, the Double Spiral Rotor Flow Meter is an upgrade product relative to Oval Gear Flow Meter, Double Spiral Rotor Flow Meter is being widely used in more and more processes which require high accuracy and reliability.
  5.  Compared with Oval Gear Flow Meter, Double Spiral Rotor Flow Meter’s size is much smaller, easy to install and maintain, has no requirement to the straight pipe length of downstream and upstream when installation.
  6. Compared with Oval Gear Flow Meter, Double Spiral Rotor Flow Meter has better viscosity adaptability (especially suitable for Non-corrosive chemical media).



Answer : Please send your question or enquiry to our email:, we will forward the questions to the related engineer.

Answer :  Please communicate with the sales about the return procedure before returning product.

Answer :  The delivery time depends on the order quantity and product specification.  If the product’s specification is conventional ( not special ),  delivery time is 5 or 7 working days for order quantity ≤ 10 pieces;  delivery time is 2 or 3 working weeks for order quantity 15 ~ 30 pieces. 

Answer :  by Courier,  by Sea or by Air

Answer :  Yes,  Generally warranty is one year.

Answer :  From year 2015  to year 2021,  average annual sales is RMB 350 million ( about USD 54.7 million )

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