Viscous Liquids - Max. Suction Flow Velocities
Avoid higher velocities in suction pipes. Higher velocities increases pressure loss in pipes and the pumps may start to cavitate. For viscous liquids - as a rule of thumb - the suction velocities in front of pumps should be below:
| Pipe bore | Max. Suction Velocity | ||
|---|---|---|---|
| inches | mm | m/s | ft/s |
| 1 | 25 | 0.3 | 1 |
| 2 | 50 | 0.33 | 1.1 |
| 3 | 75 | 0.36 | 1.2 |
| 4 | 100 | 0.4 | 1.3 |
| 6 | 150 | 0.43 | 1.4 |
| 8 | 200 | 0.45 | 1.5 |
| 10 | 250 | 0.5 | 1.7 |
| 12 | 300 | 0.5 | 1.7 |
These values depends a lot on the fluid pumped. More about viscosity and viscosities for different fluids:
- Viscosity Conversion Factors - convert between Centistokes, Centiposes, SSU and Degree Engler
- A Viscosity Converting Chart - converting table between Centiposes, milliPascal, CentiStokes and SSU
- Viscosity of common Fluids - viscosity of fluids like motor oil, diesel fuel, peanut oil and many more
Related Topics
• Fluid Flow and Pressure Loss
Pipe lines - fluid flow and pressure loss - water, sewer, steel pipes, pvc pipes, copper tubes and more.
• Piping Systems
Dimensions of pipes and tubes, materials and capacities, pressure drop calculations and charts, insulation and heat loss diagrams.
• Pumps
Piping systems and pumps - centrifugal pumps, displacement pumps - cavitation, viscosity, head and pressure, power consumption and more.
Related Documents
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Recommended max suction flow velocity when pumping boiling fluids.
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Kinematic viscosities of some common liquids like motor oil, diesel fuel, peanut oil and many more.
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Convert between viscosity units like Centiposes, milliPascal, CentiStokes and SSU.
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