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SYSTEM CHECK DUTY FOUND
Flow524 gpm
Head108 ft
BEP region95 %

Illustrative duty point — use the System Curve calculator for your data.

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Gateway calculation

Build total dynamic head before you select a pump.

Combine static elevation, pipe losses, vessel pressure, and velocity head in one defensible system requirement.

  • Clear suction lift sign convention
  • Live US and metric conversion
  • Component-by-component breakdown

Total Dynamic Head

ft
Source position relative to the pump
ft
ft
ft
psi
psi
SG
ft
Total Dynamic Head 227 ft (69.3 m)
  • Static head (h_d − h_s)+130 ft
  • Friction loss (h_fd + h_fs)+28 ft
  • Pressure head (ΔP·K/SG)+69.3 ft
  • Velocity head (Δh_v)+0 ft
Formula & method

TDH = (hd − hs) + (hfd + hfs) + (Pd − Ps)·K / SG + Δhv


			
K is the pressure-to-head constant: 2.31 ft per psi (US) or 10.2 m per bar (SI), for water at SG = 1.

		

	


	
For preliminary sizing and educational use. Verify final design against manufacturer performance curves and applicable codes; final designs should be reviewed by a licensed professional engineer.




			

		


		

			

				

					
A defensible workflow

					
From design flow to a real duty point

				

			

			
    
				
  1. 01Set flowDefine the actual process or fixture demand.
    2. 
				
  2. 02Build static headResolve elevations and pressure requirements.
    3. 
				
  3. 03Calculate lossesAdd pipe, valve, and fitting friction.
    4. 
				
  4. 04Check suctionConfirm NPSH margin and velocity limits.
    5. 
				
  5. 05Find duty pointIntersect the pump and system curves.
    6. 
			

		


					

				

					

						
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