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HI: Hydraulic Institute

HI, the Hydraulic Institute, is a nonprofit organization that develops and publishes pump standards. Headquartered in Parsippany, United States, HI membership includes most major U.S. pump manufacturers as active members. With HI standardization efforts closely linked to those of several other SDOs, HI influence goes on to spread far beyond even its own robust membership. Standards from HI are available both individually, directly through the ANSI webstore, and as part of a Standards Subscription. If you or your organization are interested in easy, managed, online access to standards that can be shared, a Standards Subscription may be what you need - please contact us at: or 1-212-642-4980 or Request Proposal Price.

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ANSI/HI 9.8-2018

Rotodynamic Pumps for Pump Intake Design

Ideally, the flow of liquid into any pump should be uniform, steady, and free from swirl and entrained air. Lack of uniformity through inlet connection can result in pumps not operating to optimum design condition and at a lower hydraulic efficiency. This technically advanced standard discusses the proper design for rectangular intakes, formed suction intakes, circular pump stations, trench-type intakes for clear liquids and for solids-bearing liquids, tanks – pump suction, can vertical turbine pump intakes, unconfined intakes, and circular plan wet pit for solids-bearing liquids.

ANSI/HI 9.6.4-2016

RotodynamicáPumps for Vibration Measurement and Allowable Values

This standard pertains to evaluation of vibration when the vibration measurements are made on nonrotating parts (bearing housings) of rotodynamic pumps. It provides specific maximum allowable vibration values measured on bearing housings of rotodynamic pumps in field and factory test environments.

ANSI/HI 9.6.1-2017

Rotodynamic Pumps Guideline for NPSH Margin

The purpose of this guideline is to establish recommended net positive suction head available (NPSHA) above the published NPSH required (NPSHR) that will lead to acceptable pump performance and service life.

ANSI/HI 11.6-2017

Rotodynamic Submersible Pumps: for Hydraulic Performance, Hydrostatic Pressure, Mechanical and Electrical Acceptance Tests

This standard applies to customer acceptance testing of rotodynamic submersible pumps driven by electric motors, unless otherwise agreed or specified. A submersible pump is defined as a close-coupled pump/motor unit designed to operate submerged in the pumped liquid. This definition includes submersible pumps operating in either a wet-pit or dry-pit environment.

ANSI/HI 9.6.6-2016

Rotodynamic Pumps for Pump Piping

ANSI/HI 9.6.6 details pump piping requirements for rotodynamic pumps and effects of inlet/outlet piping on pump performance. This standard is pplicable to all piping downstream and upstream from the pump but not when entering tank, vessel or intake structure. This document is intended to complement ANSI/HI 9.8 Intake Design for Rotodynamic Pumps.

ANSI/HI 9.6.7-2015

Rotodynamic Pumps - Guideline for Effects of Liquid Viscosity on Performance

ANSI/HI 9.6.7 outlines the method for predicting performance of rotodynamic pumps in Newtonian liquids of viscosity greater than water. The standard applies to single and multi-stage rotodynamic pumps having radial impellers ns = 60, (Ns = 3000), handling liquids exhibiting Newtonian behavior, and a kinematic viscosity greater than 1 and less than 4000 centistokes.

ANSI/HI 9.6.2-2015

Rotodynamic Pumps for Assessment of Applied Nozzle Loads

This standard includes recommendations for assessment of applied nozzle loads for the following pump types. When specified by the user, pumps supplied shall conform to these requirements. a) Horizontal end suction single stage (ANSI/ASME B73.1, B73.3, and B73.5M) b) Vertical in-line single stage (ANSI/ASME B73.2) c) Axial split case single and two stage d) Vertical turbine short set pumps

ANSI/HI 9.6.3-2017

Rotodynamc (Centrifugal and Vertical) Pumps - Guideline for Allowable Operating Region

This guideline discusses the effects of operating a rotodynamic pump continuously or for a long duration at rates of flow greater than or less than the pumpÆs best efficiency point (BEP) rate of flo

ANSI/HI 14.6-2016

Rotodynamic Pumps for Hydraulic Performance Acceptance Tests

This standard covers hydraulic performance tests for acceptance of rotodynamic pumps (centrifugal, mixed flow, and axial flow pumps). It is intended to be used for pump acceptance testing at pump test facilities, such as manufacturersÆ pump test facilities or laboratories only. Industry experience shows that it is very difficult to perform measurements accurate enough to satisfy the acceptance requirements in this standard when testing is performed in the field. Information in the standard may be applied to pumps of any size and to any pumped liquids behaving as clear water.

ANSI/HI 9.6.5-2016

Rotodynamic Pumps Guideline for Condition Monitoring

This guideline is for rotodynamic pumps, including both sealed and sealless pump designs as stated in each section.


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