Ansi Hi 9.8 Rotodynamic Pumps For Pump Intake Design (2027)
INCORRECT (Concentric) CORRECT (Flat-Side Top) ┌───────────────┐ ┌───────────────────┐ ───────┘ Air Pocket ├─── ────────┴────────┐ ├─── ▲ Coalesces │ │ │ ───────┐ Here ├─── ────────┬────────┘ ├─── └───────────────┘ └───────────────────┘ 6. Physical Model Studies: When Are They Required?
ANSI/HI 9.8-2024 is the current standard for the design and modification of rotodynamic pump intake structures, aiming to ensure uniform, steady flow while minimizing vortex formation and air entrainment. It covers diverse intake types—including rectangular, trench-type, and formed suction intakes—and provides crucial parameters for inlet bell design, minimum submergence, and acceptance criteria. For more details, visit Hydraulic Institute Store ANSI Webstore ANSI/HI 9.8-2018 - Rotodynamic Pumps for Pump Intake Design
It mandates that the fluid swirl angle entering the pump must not exceed 5 degrees . Excessive swirl alters the impeller’s angle of attack, degrading performance curves and causing structural imbalances. ansi hi 9.8 rotodynamic pumps for pump intake design
When geometric constraints prevent a structure from naturally meeting acceptance criteria, engineers implement specialized internal flow-conditioning components.
The American National Standards Institute (ANSI) and the Hydraulic Institute (HI) have collaborated to develop a comprehensive standard for the design of pump intakes for rotodynamic pumps, known as ANSI/HI 9.8. This standard provides guidelines and best practices for designing pump intakes that ensure efficient and reliable operation of rotodynamic pumps. In this write-up, we will explore the key aspects of ANSI/HI 9.8 and its significance in pump intake design. In this write-up
For critical infrastructure—such as high-flow flood control stations, cooling water loops for power plants, or intakes with non-standard approach flows—compliance with standard dimensions is not enough. ANSI/HI 9.8 mandates physical or computational validation when:
A conical structure positioned on the back wall behind the suction bell to eliminate stagnant zones and subsequent vortex shedding. cooling water loops for power plants
The Hydraulic Institute (HI) is the largest association of pump manufacturers in North America. ANSI/HI 9.8 is an American National Standard developed to provide guidelines for the design of intakes for rotodynamic pumps (centrifugal, mixed flow, and axial flow pumps).
The success of any fluid pumping system depends heavily on the geometry of its intake infrastructure. Poor intake design regularly leads to expensive mechanical failures, reduced efficiency, and premature equipment degradation. For engineering procurement and construction projects, serves as the definitive industry standard .
Apply it for:
The ANSI/HI 9.8 standard offers several benefits to pump users, designers, and manufacturers, including:
