reduce the effective density of the fluid being pumped, causing the pump to lose capacity and potentially suffer from cavitation-like damage.
ANSI/HI 9.8 establishes specific dimensional criteria that serve as the foundation of proper intake design. These criteria are expressed in terms of the pump's suction inlet diameter or bell diameter (D), ensuring that the guidance scales appropriately across pump sizes. ansi hi 9.8 rotodynamic pumps for pump intake design
[ F_D = \fracV\sqrtg \times D ]
Common remedial measures addressed by the standard include installing flow straighteners or baffles, adding splitter plates on the sump floor to control submerged vortices, modifying the approach channel geometry, adjusting pump placement within the wet well, and installing anti‑vortex devices (AVD) as outlined in ANSI/HI 9.8. reduce the effective density of the fluid being
The primary objective of the ANSI/HI 9.8 standard is to ensure that the approach flow to the pump meets strict hydrodynamic criteria. Standardized intake designs aim to achieve three specific flow conditions at the pump suction inlet: [ F_D = \fracV\sqrtg \times D ] Common
If the incoming channel is longer than 5x the sump width, HI 9.8 mandates flow conditioning. This includes:
The rectangular intake bay is the benchmark design for multiple vertical turbine or wet-pit pumps arranged in a row. ANSI/HI 9.8 prescribes explicit geometric ratios based on the pump flow rate ( ) and the suction bell diameter ( The standard recommends a minimum bay width of to prevent wall effects from distorting the approach flow. Distance from Back Wall to Pump Centerline ( ): This distance is typically set at 0.75D0.75 cap D