The Brooks® Models BM04, BM07, BM10, BM40 and BM50 are positive displacement oval gear flowmeters designed for applications requiring high accuracy measurement of clean liquids with viscosity's less than 1000 cP standard, or up to 1 million cP with rotors (gears) cut for high viscosity. All meters are available with a pulse output from a reed switch or solid state Hall effect switch for remote registration and/or totalization. Two optional LCD displays offer rate, resetable total, non-resetable total and the option for simple batch (Deluxe Display). Also offered on sizes BM10 and larger is an option for mechanical totalization. All six meters are available with PPS rotors (gears) as standard. Also available as an option are 316 SS rotors (gears).
The Model BM07 is only available with a PPS body, rotors (gears) and optional Hastelloy C® rotor (gear) shafts. The BM07 is specially designed for corrosive liquid service when the optional Hastelloy C shafts are selected. The Model BM10 is available with optional 1 inch Tri-Clover connections in all 316 Stainless Steel construction.
PRINCIPLE OF OPERATION
The oval meter is a positive displacement meter. As the fluid being measured passes through the meter, it rotates 2 oval gears in a measuring chamber to displace a precision volume of fluid. A sensor detects the gear rotation to determine displaced volume and flow rate.
Fluid pressure rotates the oval gears, Figure 1. In position 1, the fluid exerts a clockwise driving force on Gear A. There is no net driving force on Gear B. It is perpendicular to the flow so the fluid forces are balanced around the shaft. As the gears rotate to position 2, the fluid begins to exert a force on Gear B. At position 3, all the driving force is on Gear B. This alternating driving force provides a smooth rotation of almost constant torque.
The meter design minimizes the slippage between the gears and the measuring chamber wall. As a result, the oval meter is less affected than other designs by the liquid's viscosity and lubricity.
- Sizes for wide flow ranges, 0.26 to 92.5 GPM (1 to 350 LPM)
- Very low pressure drop
- Standard Viscosity to 1000 Cp (Centipoise)
- High Viscosity Rotors (Gears) to 1 million cP
- High Accuracy, 1/2% rate or better
- 0.03% repeatability
- Only two moving parts
- Reed or solid state Hall Effect Switch
- Screwed, Flanged or Tri-Clover® Connection options
- Body's available in Aluminum, PPS or 316 Stainless Steel
- Two Electronic Display options standard