ISO 9538:2025
(Main)Aerospace series — Hydraulic tubing joints and fittings — Planar flexure test
Aerospace series — Hydraulic tubing joints and fittings — Planar flexure test
This document specifies a planar flexure test procedure for reconnectable and permanent hydraulic tube joints and fittings. This procedure is intended for conducting flexure tests on fittings with high-strength hydraulic tubes made of corrosion-resisting steel, titanium and aluminium for use on commercial and military aircraft.
Série aérospatiale — Joints et raccords des tuyauteries hydrauliques — Essai de flexion plane
General Information
Relations
Standards Content (Sample)
International
Standard
ISO 9538
Third edition
Aerospace series — Hydraulic
2025-06
tubing joints and fittings — Planar
flexure test
Série aérospatiale — Joints et raccords des tuyauteries
hydrauliques — Essai de flexion plane
Reference number
© ISO 2025
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ii
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Device for flexure test . 1
5 Flexure test specimens . 3
6 Stress determination . 3
7 Procedure . 4
7.1 Instrumentation and strain gauges .4
7.2 Frequency .5
7.2.1 Test frequency .5
7.2.2 Natural frequency of the specimens .5
7.2.3 Verification of the natural frequency . .5
7.3 Bending stress calibration of test specimen .5
7.4 Test .5
8 Requirements . 5
Bibliography . 7
iii
Foreword
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This document was prepared by Technical Committee ISO/TC 20, Aircraft and space vehicles, Subcommittee
SC 10, Aerospace fluid systems and components.
This third edition cancels and replaces the second edition (ISO 9538:2017), which has been technically
revised.
The main changes are as follows:
— Clause 4 and Clause 7 were updated.
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