Ansi Hi 9.8 Rotodynamic Pumps For Pump Intake Design

ANSI/HI 9.8 – Rotodynamic Pumps for Pump Intake Design

Here’s a useful, structured content piece on , aimed at engineers, plant operators, and design professionals.

Key Benefits of ANSI/HI 9.8

Importance of Pump Intake Design

• Swirl & pre-rotation → Reduces pump efficiency and head, increases shaft deflection.
• Vortices (surface, subsurface, air-core) → Causes vibration, cavitation, noise, and capacity loss.
• Air entrainment → Loss of prime, erratic operation, accelerated wear.
• Flow separation & uneven velocity profile → Hydraulic thrust loading, bearing failure.

Vortex Prevention

: Establishing minimum submergence levels and geometry requirements to stop surface or submerged vortices from drawing air into the pump. ansi hi 9.8 rotodynamic pumps for pump intake design

Applying ANSI/HI 9.8 to Optimize Pump Intake Design

B. Submergence (S)

"The standard suggests a minimum straight run of pipe," Elias said. "But this geometry? It’s compromised. We need to break the flow. We need to tame it before it hits the eye of the impeller." ANSI/HI 9

If the incoming channel is longer than 5x the sump width, HI 9.8 mandates flow conditioning. This includes: Swirl & pre-rotation → Reduces pump efficiency and