Technical Update

18 Dec 2020

Calling all pump and motor manufacturers…

The ISO standard which describes the method for determining the derived displacement of positive displacement pumps and motors, ISO 8426:2008, is being updated.

The technical committee responsible for the revised standard has asked for a round robin of inter-laboratory testing, inviting any users of the standard who wish to validate the proposed new methodology to get in touch.

If you can help with the testing or would like any further information, please contact Mr Steve Clarke at

Renaissance in Water Hydraulics

By Mark Fairhurst, Senior Engineer, BHR Group, Chairman SC 8 Product Testing – UK Expert WG14 – Testing of Water Hydraulic Pumps

A new working group has been set up to develop a standard for the testing of water-hydraulic pumps, ISO/TC 131/SC 8/WG 14. The Japanese are leading the working group as there has been a significant increase in interest in ‘Aqua Drive Systems’, especially in food processing and electronic component manufacture within Japan. The UK’s appetite for water hydraulics seems to run ‘hot and cold’, but there are obvious opportunities for UK knowhow and products within this emerging market that have been derived from several decades of development here in the UK.

Without standards designed specifically for water hydraulics the industry has been forced to adapt oil hydraulic standards and that can lead to interpretation of the methods and results. Helping to develop international water hydraulic standards ensures that they encompass UK expertise, are fit for purpose and not restrictive to the potential worldwide export of UK products and services.

The current standard under development is ISO 23840 Water-hydraulics –Water-hydraulic pumps – Methods of testing and representing basic steady state. The working group has representatives from six countries and plans to develop control valve standards as the next priority.

If you would like any more information on any of these standards or topics or are interested in joining a BFPA Technical Committee, please contact Yvonne Pearman