ISO 23933:2006

Aerospace — Aramid reinforced lightweight polytetrafluoroethylene (PTFE) hose assemblies, classification 135 degrees C/20 684 kPa (275 degrees F /3 000 psi) and 135 degrees C/21 000 kPa (275 degrees F/3 046 psi) — Procurement specification

ISO 23933:2006 specifies requirements for aramid reinforced lightweight polytetrafluoroethylene (PTFE) hose assemblies for use in aircraft hydraulic, oil and fuel systems at temperatures between -55 °C and 135 °C (-65 °F and 275 °F) and at a nominal pressure of 21 000 kPa (210 bar) (3 046 psi) or 20 684 kPa (3 000 psi). The hose assemblies are also suitable for use within the same temperature and pressure limitations in aircraft pneumatic systems where some gaseous diffusion through the wall of the PTFE liner may be tolerated.

Aéronautique et espace — Tuyauteries flexibles en polytétrafluoroéthylène (PTFE) renforcement aramide, série légère, classification 135 degrés C/ 20 684 kPa (275 degrés F/3 000 psi) et 135 degrés C/21 000 kPa (275 degrés F/3 046 — Spécification d'approvisionnement

General Information

• Status: Published
• Publication Date: 19-Jan-2006
• ICS: 49.080 - Aerospace fluid systems and components
• Technical Committee: ISO/TC 20/SC 10 - Aerospace fluid systems and components
• Drafting Committee: ISO/TC 20/SC 10/WG 14 - Hose assemblies
• Current Stage: 9093 - International Standard confirmed
• Completion Date: 06-Nov-2020

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 23933
First edition
2006-01-15

Aerospace — Aramid reinforced
lightweight polytetrafluoroethylene
(PTFE) hose assemblies, classification
135 °C/20 684 kPa (275 °F/3 000 psi) and
135 °C/21 000 kPa (275 °F/3 046 psi) —
Procurement specification
Aéronautique et espace — Tuyauteries flexibles en
polytétrafluoroéthylène (PTFE) renforcement aramide, série légère,
classification 135 °C/20 684 kPa (275 °F/3 000 psi) et
135 °C/21 000 kPa (275 °F/3 046 psi) — Spécification
d'approvisionnement



Reference number
ISO 23933:2006(E)
©
ISO 2006

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ISO 23933:2006(E)
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ISO 23933:2006(E)
Contents Page
Foreword. iv
1 Scope.1
2 Normative references.1
3 Classification.2
4 Requirements.2
4.1 Limits of application.2
4.2 Qualification.2
4.3 Materials.2
4.4 Construction.3
4.5 Inner tube requirements.4
4.6 Hose assembly.5
4.7 Fitting threads.6
4.8 Part numbering of interchangeable parts .7
4.9 Identification of products.7
4.10 Workmanship.7
4.11 Hose assembly — Test and performance requirements .8
5 Quality assurance.12
5.1 Responsibility for inspection .12
5.2 Classification of inspections.12
5.3 Qualification inspections .12
5.4 Quality conformance inspections.15
5.5 Test conditions .16
5.6 Inspection methods.17
6 Preparation for delivery .18
6.1 Storage and packaging .18
6.2 Marking.18
7 Ordering data .18
Annex A (informative) Equivalent materials .19
Annex B (informative) Qualification procedures and fire resistance specifications .21
Bibliography .22

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ISO 23933:2006(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
(ISO member bodies). The work of preparing International Standards is normally carried out through ISO
technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the
International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 23933 was prepared by Technical Committee ISO/TC 20, Aircraft and space vehicles, Subcommittee
SC 10, Aerospace fluid systems and components.

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INTERNATIONAL STANDARD ISO 23933:2006(E)

Aerospace — Aramid reinforced lightweight
polytetrafluoroethylene (PTFE) hose assemblies, classification
135 °C/20 684 kPa (275 °F/3 000 psi) and 135 °C/21 000 kPa
(275 °F/3 046 psi) — Procurement specification
1 Scope
This International Standard specifies requirements for aramid reinforced lightweight polytetrafluoroethylene
(PTFE) hose assemblies for use in aircraft hydraulic, oil and fuel systems at temperatures between − 55 °C
and 135 °C (− 65 °F and 275 °F) and at a nominal pressure of 21 000 kPa (210 bar) (3 046 psi) or 20 684 kPa
(3 000 psi). The hose assemblies are also suitable for use within the same temperature and pressure
limitations in aircraft pneumatic systems where some gaseous diffusion through the wall of the PTFE liner may
be tolerated.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
ISO 2685:1998, Aircraft — Environmental test procedure for airborne equipment — Resistance to fire in
designated fire zones
ISO 2859-1, Sampling procedures for inspection by attributes — Part 1: Sampling schemes indexed by
acceptance quality limit (AQL) for lot-by-lot inspection
ISO 3161:1999, Aerospace — UNJ threads — General requirements and limit dimensions
ISO 5855-3:1990, Aerospace — MJ threads — Part 3: Limit dimensions for fittings for fluid systems
ISO 6772:1988, Aerospace — Fluid systems — Impulse testing of hydraulic hose, tubing and fitting
assemblies
ISO 7258:1984, Polytetrafluoroethylene (PTFE) tubing for aerospace applications — Methods for the
determination of the density and relative density
ISO 8829-2, Aerospace — Test methods for polytetrafluoroethylene (PTFE) innertube hose assemblies —
Part 2: Non-metallic braid
SAE AS 150, Hose assembly, type classifications of, basic performance and fire resistance
SAE AS 1055, Fire testing of flexible hose, tube assemblies, coils, fittings and similar system components
SAE AS 1241, Fire resistant phosphate ester hydraulic fluid for aircraft
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ISO 23933:2006(E)
3 Classification
Hose assemblies furnished under this International Standard shall be classified as follows:
⎯ Type A: 20 684 kPa (3 000 psi) nominal pressure;
⎯ Type B: 21 000 kPa (210 bar) (3 046 psi) nominal pressure.
When no classification is specified by reference to this standard, type B shall apply.
4 Requirements
4.1 Limits of application
The use of these hose assemblies in high-pressure pneumatic storage systems is not recommended. In
addition, installations in which the limits specified in this International Standard are exceeded or in which the
application is not covered specifically by this International Standard, for example for oxygen, shall be subject
to the approval of the purchaser.
4.2 Qualification
4.2.1 General
Hose assemblies supplied in accordance with this International Standard shall be representative of products
which have been subjected to and which have successfully passed the requirements and tests specified in
this International Standard.
4.2.2 Manufacturer qualification
Manufacturer approval shall be granted by outside agency procedure (see Table B.1, Procedure no. 1).
4.2.3 Product qualification
Product approval shall be granted by outside agency procedure (see Table B.1, Procedure no. 2).
4.3 Materials
4.3.1 General
The hose assembly materials shall be as described in this International Standard. All materials not specifically
described in this International Standard shall be of the highest quality and suitable for the purpose intended.
4.3.2 Metals
Metals used in the fittings shall conform to the applicable specifications described in Table 1 (or equivalent
specifications; see Annex A). Welded and redrawn tubing shall not be used. Material no. 1 shall not be used
for welded assemblies.
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ISO 23933:2006(E)
Table 1 — Metals to be used in hose assemblies
Material no.
Form Metal
(see Annex A)
Austenitic, annealed or as-rolled, corrosion-resistant steel 1
Austenitic, annealed or as-rolled, stabilized, corrosion-resistant steel 2 and 3
Bars and
forgings
Precipitation-hardening, corrosion-resistant steel 4, 5 and 6
Titanium 6Al-4V 7
CPTi 8
Austenitic, seamless or welded, annealed, corrosion-resistant steel 9
Tubing
Austenitic, seamless or welded, stabilized, corrosion-resistant steel 10 and 11
Cold-worked, stress-relieved titanium alloy 12

4.4 Construction
4.4.1 General
To meet the construction and performance requirements laid down in this International Standard and as
required for its intended use, the hose assembly shall consist of:
⎯ a seamless PTFE inner tube (see 4.4.2);
⎯ treated para-aramid reinforcement (see 4.4.3);
⎯ outer cover or braid protection to meet qualification and usability requirements;
⎯ corrosion-resistant steel and/or titanium end-fittings (see 4.4.4).
4.4.2 Inner tube
The inner tube shall be of a seamless construction of virgin PTFE resin of uniform gauge. It shall have a
smooth bore and shall be free from pitting or projections on the inner surface. Additives may be included in the
compound from which the tube is extruded with no more than 3 % of such additives being retained in the
mixture.
4.4.3 Reinforcement
The reinforcement shall consist of a treated para-aramid braid and an outer braid or other coverage to protect
the para-aramid.
The reinforcement shall be arranged on the outside surface of the inner tube so as to provide sufficient
strength to ensure compliance with the requirements laid down in this International Standard. Broken,
damaged, slack or missing reinforcement yarn shall be cause for rejection.
The outer cover, or braid, shall provide 100 % coverage to protect the para-aramid reinforcement from
exposure to ultraviolet light when bending to minimum radius specified in Table 4.
A continuous lay line which can be interrupted with hose manufacturer’s name or trademark, shall be
permanently marked in contrasting colour along the hose length.
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ISO 23933:2006(E)
4.4.4 Fittings
4.4.4.1 General
It shall be proven that all fittings comply with the requirements laid down in this International Standard. Hose
assemblies supplied under this International Standard shall be equipped with fittings qualified for their
intended use.
4.4.4.2 Insert fittings
Insert fittings shall be manufactured in one piece wherever possible. Those made of other than one-piece
construction shall be butt-welded, fabricated unless otherwise agreed by the purchaser, from corrosion-
resistant steel or titanium tubing.
4.5 Inner tube requirements
4.5.1 Density and relative density
3
The relative density of the hose inner tube shall not exceed 2,155 g/cm , when tested in accordance with
ISO 7258, either method A or method B (as specified in ISO 8829-2). The density shall not exceed
3
2,204 g/cm , when tested in accordance with ISO 7258, method C (as specified in ISO 8829-2).
4.5.2 Tensile strength
When tested in accordance with ISO 8829-2, 4.2, the longitudinal tensile strength for all sizes of tubes shall be
2 2
at least 15,1 N/mm (1 N/mm = 1 MPa) (2 200 psi).
When tested in accordance with ISO 8829-2, 4.2, the transverse tensile strength for sizes DN 16 (− 10) and
2
larger shall be at least 12,4 N/mm (1 800 psi); for sizes under DN 16 (− 10), the transverse strength need not
be tested.
4.5.3 Elongation
When tested in accordance with ISO 8829-2, 4.2, elongation shall be at least 200 %.
4.5.4 Tube roll
The tube shall not leak, split, burst or show any signs of malfunction, when tested through the sequence as
specified in 4.3.2 of ISO 8829-2.
4.5.5 Tube proof pressure
After being subjected to the tube roll test sequence (see 4.5.4), the tube, without reinforcing yarns, shall not
leak, burst or show any signs of malfunction, when tested as specified in 4.3.3 of ISO 8829-2.
4.5.6 Electrical conductivity
When tested in accordance with 4.4 of ISO 8829-2, the electrical current shall be equal to or greater than:
⎯ 10 µA for sizes DN 06 to DN 12 inclusive (−04 to −08 inclusive);
⎯ 20 µA for sizes DN 16 (−10) and over.
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ISO 23933:2006(E)
4.6 Hose assembly
4.6.1 Dimensional requirements
The hose assembly dimensions, except for length, shall be as specified in Figure 1 and Table 2A or Table 2B,
as useful.
4.6.2 Physical requirements
The hose assembly shall comply with the physical and linear density (weight) requirements specified in
Table 4.

Key
a
width across corners of nut and socket hexagon
d inside diameter (hose)

h
D outside diameter (hose)
h
d inside diameter (fitting)
f
D outside diameter (fitting)
f
l attachment length
δ wall thickness of inner tube
Figure 1 — Hose and fitting dimensions
4.6.3 Bore check
When bent to appropriate minimum bend radius as specified in Table 4, the hose assembly shall permit the
free passage of a solid rigid sphere throughout its length. The minimum diameter of the sphere is given in
Table 2A or Table 2B, as useful.
4.6.4 Assembly length
Tolerances on hose assembly lengths shall be as follows (unless otherwise specified):
⎯ ± 3,20 mm (± 0,125 in) for lengths under 500 mm (19,6 in);
⎯ ± 6,35 mm (± 0,250 in) for lengths from 500 mm to 1 000 mm (19,6 in to 39,4 in) exclusive;
⎯ ± 12,70 mm (± 0,500 in) for lengths from 1 000 mm to 1 500 mm (39,4 in to 59 in) exclusive;
⎯ ± 1 % for lengths of 1 500 mm (59 in) and over.
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ISO 23933:2006(E)
4.7 Fitting threads
Unless otherwise specified (see 4.4.4), fitting threads shall be in accordance with ISO 5855-3 for SI (metric
series) fittings and ISO 3161 for imperial (inch series) fittings. A 10 % increase in the tolerance of the fitting
thread of the nut following proof pressure test shall not be cause for rejection of the hose assembly.
Table 2A — Hose and fitting dimensions as shown in Figure 1 — SI units
Dimensions in millimetres
Hose size Attach- Wall Spherical
(nom.) ment thick- ball size for
Hose (braided) Fitting
length ness hose assembly
Inch part b
of
inside diameter

inner
Metric
Inside Outside Inside Outside
tube

a
part
Equivalent tube Straight Elbow
diameter diameter diameter diameter
outside diameter fittings fittings
δ
d D d l
D
h h f
f
Size Size mm (in) min. min. max. min. max. max. min. min. min.
DN 06 − 04 6,350 (0,250) 5,4 10,0 11,0 3,4 14 22 0,89 3,06 2,89
DN 10 − 06 9,525 (0,375) 7,6 12,6 14,0 6,1 18 35 0,89 5,49 5,19
DN 12 − 08 12,700 (0,500) 9,9 15,5 16,5 8,6 20 40 1,02 7,74 7,31
DN 16 − 10 15,875 (0,625) 12,3 19,0 20,0 10,4 24 47 1,14 9,36 8,84
DN 20 − 12 19,050 (0,750) 15,3 22,5 23,5 12,9 28 54 1,14 11,61 10,97
DN 25 − 16 25,400 (1,000) 21,6 31,4 32,5 19,3 37 66 1,14 17,37 16,41
a
Width across corners of nut and socket hexagon may exceed the values given for D .
f
b
Minimum specified inside diameter shall be verified by passing a spherical ball through the hose assembly (see 4.6.3).

Table 2B — Hose and fitting dimensions as shown in Figure 1 — Imperial units
Dimensions in inches
Hose size Attach- Wall Spherical
(nom.) ment thick- ball size for
Hose (braided) Fitting length ness hose assembly
of inside
Inch part

b
inner
diameter
Metric
tube

Inside Outside Inside Outside
part
Equivalent tube Straight Elbow
a
diameter diameter diameter diameter
outside diameter fittings fittings
d D d D
δ
l
h h f f
Size Size mm (in) min. min. max. min. max. max. min. min. min.
DN 06 − 04 6,350 (0,250) 0,213 0,394 0,433 0,134 0,551 0,866 0,035 0,120 0,114
DN 10 − 06 9,525 (0,375) 0,299 0,496 0,551 0,240 0,709 1,378 0,035 0,216 0,204
DN 12 − 08 12,700 (0,500) 0,390 0,650 0,650 0,339 0,787 1,575 0,040 0,305 0,288
DN 16 15,875 (0,625) 0,384 0,787 0,787 0,409 0,945 1,850 0,045 0,369 0,348
− 10
DN 20 − 12 19,050 (0,750) 0,602 0,886 0,925 0,508 1,102 2,126 0,045 0,457 0,432
DN 25 − 16 25,400 (1,000) 0,850 1,236 1,280 0,760 1,457 2,598 0,045 0,684 0,646
a
Width across corners of nut and socket hexagon may exceed the values given for D .
f
b
Minimum specified inside diameter shall be verified by passing a spherical ball through the hose assembly (see 4.6.3).

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ISO 23933:2006(E)
4.8 Part numbering of interchangeable parts
All parts complying with this International Standard and having the same manufacturer’s or standard part
number shall be functionally and dimensionally interchangeable.
4.9 Identification of products
4.9.1 General
The hose assembly and its removable component parts shall be permanently marked.
4.9.2 Fittings
The manufacturer’s name or trademark shall be permanently marked on one element of all removable end
fittings.
4.9.3 Hose assembly
A permanent marking shall be applied on a permanent rigid part and/or on a permanent band or bands
securely attached to the hose. Bands shall be no wider than 25,4 mm (1 in) and shall not impair the flexibility
or the performance of the hose. Unless otherwise specified by the purchaser, the marking on the fitting or
band shall include the following information:
⎯ the hose assembly manufacturer’s name, trademark (optional);
⎯ the hose assembly manufacturer’s CAGE/NATO code;
⎯ the complete hose assembly part number;
⎯ the number of this International Standard followed by either the applicable type (A or B) or the applicable
nominal pressure (“21 000 kPa” or “3 000 psi”);
⎯ the maximal operating temperature “135 °C” (275 °F) if and as required by the purchaser;
⎯ the pressure test symbol “PT” or quality control label;
⎯ the date of hose assembly manufacture or batch number as required by the purchaser;
⎯ the fire resistance type per ISO 2685, SAE AS 1055 or SAE AS 150 if applicable and as required by the
purchaser.
4.10 Workmanship
4.10.1 General
Workmanship shall be of such quality as to assure that hose assemblies furnished under this International
Standard are free of defects that compromise, limit or reduce performance or intended use.
Hose assemblies shall be free of burrs, scratches, sharp edges, loose components, chips or foreign materials.
4.10.2 Dimensions and tolerances
All pertinent dimensions and tolerances, where interchangeability, operation or performance of the hose
assembly may be affected, shall be specified on all drawings.
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ISO 23933:2006(E)
4.10.3 Cleaning
All hose assemblies shall be free from water, oil, grease, dirt or other foreign materials, both internally and
externally.
4.11 Hose assembly — Test and performance requirements
4.11.1 Proof pressure
When tested in accordance with ISO 8829-2, 5.8, each hose assembly shall withstand the proof pressure
specified in Table 3A or Table 3B, as applicable, without malfunction or leakage.
Table 3A — Pressure requirements of type A hose assemblies
Hose size
Nominal Proof Minimum burst pressure
pressure pressure at
Inch part
Metric
Equivalent tube high
part
room temperature

outside diameter temperature
Size Size mm (in) kPa (psi) kPa (psi) kPa (psi) kPa (psi)
DN 06 6,350 (0,250) 20 684 (3 000) 41 370 (6 000) 110 320 (16 000) 82 740 (12 000)
− 04
DN 10 9,525 (0,375) 20 684 (3 000) 41 370 (6 000) 96 530 (14 000) 72 398 (10 500)
− 06
DN 12 − 08 12,700 (0,500) 20 684 (3 000) 41 370 (6 000) 96 530 (14 000) 72 398 (10 500)
DN 16 − 10 15,875 (0,625) 20 684 (3 000) 41 370 (6 000) 82 740 (12 000) 62 055 (9 000)
DN 20 − 12 19,050 (0,750) 20 684 (3 000) 41 370 (6 000) 82 740 (12 000) 62 055 (9 000)
DN 25 − 16 25,400 (1,000) 20 684 (3 000) 41 370 (6 000) 82 740 (12 000) 62 055 (9 000)

Table 3B — Pressure requirements of type B hose assemblies
Hose size
Nominal Proof Minimum burst pressure
pressure pressure at
Inch part
Metric
Equivalent tube high
part
room temperature

outside diameter temperature
Size Size mm (in) kPa (psi) kPa (psi) kPa (psi) kPa (psi)
DN 06 6,350 (0,250) 21 000 (3 046) 42 000 (6 091) 84 000 (12 183) 63 000 (9 137)
− 04
DN 10 − 06 9,525 (0,375) 21 000 (3 046) 42 000 (6 091) 84 000 (12 183) 63 000 (9 137)
DN 12 − 08 12,700 (0,500) 21 000 (3 046) 42 000 (6 091) 84 000 (12 183) 63 000 (9 137)
DN 16 − 10 15,875 (0,625) 21 000 (3 046) 42 000 (6 091) 84 000 (12 183) 63 000 (9 137)
DN 20 19,050 (0,750) 21 000 (3 046) 42 000 (6 091) 84 000 (12 183) 63 000 (9 137)
− 12
DN 25 − 16 25,400 (1,000) 21 000 (3 046) 42 000 (6 091) 84 000 (12 183) 63 000 (9 137)

4.11.2 Elongation and contraction
When sample hose assemblies are tested in accordance with ISO 8829-2, 5.5, there shall be no change in
length by more than ± 2 % in a 250 mm (10 in) gauge length.
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ISO 23933:2006(E)
4.11.3 Volumetric expansion
When sample hose assemblies are tested in accordance with ISO 8829-2, 5.6, the volumetric expansion shall
not exceed the limits specified in Table 4.
Table 4 — Physical requirements of hose assemblies and linear density (weight) of hose
Hose size
Linear density (weight) Bend radius
Volumetric expansion
a
of hose at inside of bend
Inch part
Metric
Equivalent tube
part
max. min. max.
outside diameter
3
Size Size mm (in) kg/m (lb/in) mm (in) ml/m (cm /in)
DN 06 − 04 6,350 (0,250) 0,100 (0,006) 38 (1,50) 3,5 (0,089)
DN 10 − 06 9,525 (0,375) 0,120 (0,007) 63 (2,48) 5,2 (0,132)
DN 12 − 08 12,700 (0,500) 0,170 (0,010) 73 (2,87) 7,4 (0,188)
DN 16 15,875 (0,625) 0,235 (0,013) 82 (3.23) 15,1 (0,384)
− 10
DN 20 − 12 19,050 (0,750) 0,300 (0,017) 101 (3,98) 19,4 (0,493)
DN 25 25,400 (1,000) 0,530 (0,030) 127 (5,00) 44,6 (1,133)
− 16
a
The linear density (weight) of the hose shall be determined on a minimum length of 300 mm (11,8 in).

4.11.4 Leakage
When sample hose assemblies are tested in accordance with ISO 8829-2, 5.7, there shall be no leakage.
4.11.5 Thermal shock
4.11.5.1 Preconditioning
Following sample hose assemblies shall be tested:
⎯ one test specimen shall be oil/air-aged;
⎯ one test specimen shall be light ray-aged (when required); and
⎯ one test specimen shall be unaged (see 5.5.6).
4.11.5.2 Requirement
When tested in accordance with ISO 8829-2, with a maximum temperature of 135 °C (275 °F), the test
specimens shall neither leak nor show any signs of malfunction during the proof pressure phase of the test;
during the burst pressure phase of the test, if leakage or signs of malfunction occur below the minimum burst
pressure at the high temperature specified in Table 3A or Table 3B, as applicable, the sample shall be
deemed to have failed.
4.11.6 Impulse
4.11.6.1 Preconditioning
Following sample hose assemblies having a 90° elbow fitting on one end of the hose and a straight fitting on
the other end of the hose shall be tested. Two test specimens shall be oil/air-aged, two shall be light ray-aged
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ISO 23933:2006(E)
(when required) and two unaged (see 5.5.6). If approval is being sought for both the bent-tube and the forged
elbow configuration, then one half of the specimens shall be of each configuration.
After this initial preconditioning, the test specimens shall be subjected at room temperature to the proof
pressure specified in Table 3A or Table 3B, as applicable, for at least 5 min. The test specimens shall then be
pressurized to the nominal pressure specified in Table 3A or Table 3B, as applicable.
4.11.6.2 Requirement
When tested for 250 000 cycles at nominal pressure specified in Table 3A or Table 3B, as applicable, in
accordance with ISO 8829-2 (i.e. in accordance with ISO 6772), with a maximum temperature of 135 °C
(275 °F), the sample hose assemblies shall comply with the test requirements without any signs of leakage
[see also item g) in Clause 7]. The test specimens shall be mounted in a test setup shown in ISO 8829-2
having the dimension specified in Table 5.
For sizes over DN16 (-10), the hose assembly may be bent in a 90° configuration, in lieu of 180° as defined in
5.10 of ISO 8829-2, at a reduced length as noted in Table 8, to reduce fluid volume.
4.11.7 Flexure
When sample hose assemblies are flexure-tested in accordance with ISO 8829-2, with a maximum
temperature of 135 °C (275 °F), they shall not leak or show any other signs of malfunction. The test
specimens shall be mounted in a test setup shown in ISO 8829-2 having the dimension specified in Table 5.
Table 5 — Flexure test and impulse test dimension
Hose size
length
l
Inch part
Metric
Equivalent tube
part
(approx.)
outside diameter
Size Size mm (in) mm (in)
DN 06 6,350 (0,250) 89 (3,5)
− 04
DN 10 9,525 (0,375) 143 (5,6)
− 06
DN 12 − 08 12,700 (0,500) 165 (6,5)
DN 16 − 10 15,875 (0,625) 184 (7,3)
DN 20 − 12 19,050 (0,750) 229 (9,0)
DN 25 25,400 (1,000) 282 (11,1)
− 16

4.11.8 Stress degradation
When sample hose assemblies are tested in accordance wi
...