Overview
EN ISO 9905:1997/A1:2011 is Amendment 1 to ISO 9905:1994, the international/European technical specification for Class I centrifugal pumps. Published and endorsed by CEN in April 2011, this amendment is explicitly minor and mainly updates normative references and cross-references to align pump specification and test clauses with the then-upcoming revision of the hydraulic performance test standard.
Key topics and requirements
- Scope: Technical specifications for rotodynamic (centrifugal) pumps designated as Class I-covers performance, testing references, and certain material and vibration cross-references.
- Normative reference updates:
- NPSH (NPSHR) specification: Net positive suction head required (NPSHR) shall be based on cold water in accordance with ISO 9906 unless otherwise agreed (replacing older ISO references).
- Testing and performance cross-references:
- Hydraulic performance tests and NPSH tests are now specified to follow ISO 9906.
- Clause and figure cross-references updated to point to ISO 9906 for definitions (for example, definition of K and other test-related terms).
- Editorial corrections:
- Removal of outdated footnotes and deletion of obsolete source citations in table and figure titles (e.g., Table 1 and Figure E.1).
- Material table (Table J.1) updated to remove the ISO 427 citation for bronze.
Applications
- Pump manufacturers: to align product specifications, documentation and test reports with current international/European requirements for Class I centrifugal pumps.
- Test laboratories and QA teams: to perform hydraulic performance and NPSH testing in accordance with the referenced ISO 9906 acceptance grades.
- Engineers and specifiers: to reference the correct normative standards when designing systems or procuring pumps for industrial, municipal or process applications.
- Procurement and compliance officers: to ensure purchased equipment meets EN/ISO conformance as adopted by CEN national bodies.
Related standards and context
- Primary related standard: ISO 9906 (Rotodynamic pumps - Hydraulic performance acceptance tests) - amendment aligns EN ISO 9905 test references with ISO 9906.
- The amendment was implemented across CEN member national standards bodies and is an editorial/registration update to maintain consistency with revised test methods.
Keywords: centrifugal pump standard, EN ISO 9905 amendment, Class I centrifugal pumps, NPSHR, hydraulic performance tests, ISO 9906, pump testing, CEN compliance.