Aerospace — Lightweight polytetrafluoroethylene (PTFE) hose assemblies, classification 400 degrees F/3 000 psi (204 degrees C/20 684 kPa) and 204 degrees C/21 000 kPa (400 degrees F/3 046 psi) — Procurement specification

ISO 8913:2006 specifies requirements for lightweight polytetrafluoroethylene (PTFE) hose assemblies for use in aircraft hydraulic systems at temperatures between - 55 °C and 204 °C (- 65 °F and 400 °F), and at a nominal pressure up to 3 000 psi (20 684 kPa) or 21 000 kPa (3 046 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 on the PTFE liner may be tolerated. The use of these hose assemblies in high-pressure pneumatic storage systems is not recommended. In addition, installations in which the limits specified in ISO 8913:2006 are exceeded, or in which the application is not covered specifically by ISO 8913:2006, for example for oxygen, are subject to the approval of the purchaser. A listing of hose assembly procurement standards conforming to ISO 8913:2006 is given.

Aéronautique et espace — Tuyauteries flexibles en polytétrafluoroéthylène (PTFE), série légère, classification 400 degrés F/3 000 psi (204 degrés C/20 684 kPa) et 204 degrés C/21 000 kPa (400 degrés F/3 046 psi) — Spécification d'approvisionnement

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Status
Published
Publication Date
29-Oct-2006
Current Stage
9092 - International Standard to be revised
Completion Date
29-Nov-2021
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ISO 8913:2006 - Aerospace -- Lightweight polytetrafluoroethylene (PTFE) hose assemblies, classification 400 degrees F/3 000 psi (204 degrees C/20 684 kPa) and 204 degrees C/21 000 kPa (400 degrees F/3 046 psi) -- Procurement specification
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INTERNATIONAL ISO
STANDARD 8913
Third edition
2006-11-01

Aerospace — Lightweight
polytetrafluoroethylene (PTFE) hose
assemblies, classification
400 °F/3 000 psi (204 °C/20 684 kPa) and
204 °C/21 000 kPa (400 °F/3 046 psi) —
Procurement specification
Aéronautique et espace — Tuyauteries flexibles en
polytétrafluoroéthylène (PTFE), série légère, classification
400 °F/3 000 psi (204 °C/20 684 kPa) et 204 °C/21 000 kPa
(400 °F/3 046 psi) — Spécification d'approvisionnement




Reference number
ISO 8913:2006(E)
©
ISO 2006

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ISO 8913:2006(E)
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ii © ISO 2006 – All rights reserved

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ISO 8913:2006(E)
Contents Page
Foreword. iv
Introduction . v
1 Scope . 1
2 Normative references . 1
3 Classification. 2
4 Requirements . 2
4.1 Qualification . 2
4.2 Materials . 2
4.3 Construction. 3
4.4 Inner tube. 4
4.5 Hose . 5
4.6 Screw threads . 7
4.7 Part numbering of interchangeable parts . 7
4.8 Identification of products. 7
4.9 Workmanship . 8
4.10 Hose assembly — Test and performance requirements . 8
5 Quality assurance. 13
5.1 Responsibility for inspection . 13
5.2 Classification of inspections . 13
5.3 Qualification inspections . 13
5.4 Quality conformance inspections . 15
5.5 Test conditions . 17
5.6 Inspection methods. 18
6 Preparation for delivery . 18
6.1 Storage and packaging . 18
6.2 Marking . 18
7 Ordering data . 18
Annex A (informative) Equivalent hose assembly product standards governed by ISO 8913 . 20
Annex B (normative) Equivalent national qualification procedure and fire resistance specification. 21
Annex C (informative) Equivalent materials . 22
Bibliography . 25

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ISO 8913:2006(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 8913 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 8913:1994). Criteria for imperial dimension
(inch-based) hose assemblies as used for commercial aviation are being introduced.
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ISO 8913:2006(E)
Introduction
This International Standard establishes the basic performance and quality requirements for lightweight
polytetrafluoroethylene (PTFE) hose assemblies for use in aerospace fluid systems.
The procurement requirements are intended to ensure that hose assemblies which are procured in
accordance with this specification are of the same quality as the hose assemblies used during the original
qualification testing. Compliance with these test and procurement requirements is necessary for hose
assemblies that are used in fluid systems where a malfunction would affect the safety of flight.

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INTERNATIONAL STANDARD ISO 8913:2006(E)

Aerospace — Lightweight polytetrafluoroethylene (PTFE) hose
assemblies, classification 400 °F/3 000 psi (204 °C/20 684 kPa)
and 204 °C/21 000 kPa (400 °F/3 046 psi) — Procurement
specification
1 Scope
This International Standard specifies requirements for lightweight polytetrafluoroethylene (PTFE) hose
assemblies for use in aircraft hydraulic systems at temperatures between − 55 °C and 204 °C (− 65 °F and
400 °F), and at a nominal pressure up to 3 000 psi (20 684 kPa) or 21 000 kPa (3 046 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 on the PTFE liner may be tolerated.
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, are subject to the
approval of the purchaser.
Annex A is a listing of hose assembly procurement standards conforming to this International Standard.
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 2859-1:1999, 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 5855-3:1999, 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 8829:1990, Aerospace — Polytetrafluoroethylene (PTFE) hose assemblies — Test methods
ISO 8829-2, Aerospace — Test methods for polytetrafluoroethylene (PTFE) inner-tube hose assemblies —
Part 2: Non-metallic braid
EN 9100, Aerospace series — Quality management systems — Requirements (based on ISO 9001:2000) and
Quality systems — Model for quality assurance in design, development, production, installation and servicing
(based on ISO 9001:1994)
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ISO 8913:2006(E)
EN 9133, Aerospace series — Quality management systems — Qualification procedure for aerospace
standard parts
SAE AS150, Hose assembly, type classifications of, basic performance and fire resistance
SAE AS1055, Fire testing of flexible hose, tube assemblies, coils, fittings and similar system components
SAE AS7003, Nadcap program requirements
SAE AS7112, National aerospace and defense contractors accreditation program (Nadcap) requirements for
fluid system components
ASTM A262, Standard practices for detecting susceptibility to intergranular attack in austenitic stainless steels
PRI PD2101, Aerospace quality assurance, product standards, qualification procedure, fluid systems
3 Classification
Hose assemblies furnished under this International Standard shall be classified as follows:
⎯ Type A — 3 000 psi (20 684 kPa) pressure system,
⎯ Type B — 21 000 kPa (3 046 psi) pressure system.
When no classification is specified by reference to this International Standard, type B shall apply.
4 Requirements
4.1 Qualification
4.1.1 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.
4.1.2 Manufacturer qualification
Manufacturer approval shall be granted by outside agency procedure as specified in Table B.1, procedure
no. 1).
4.1.3 Product qualification
Product approval shall be granted by outside agency procedure as specified in Table B.1, procedure no. 2.
4.2 Materials
4.2.1 General
The hose assembly materials shall be as described in this International Standard (see, in particular,
Table C.1). All materials not specifically described in this International Standard shall be of the highest quality
and suitable for the purpose intended.
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ISO 8913:2006(E)
4.2.2 Metals
Metals used in the hose and fittings shall be corrosion-resistant steel, nickel alloy or titanium, and shall
conform to the applicable specifications given in Table 1 (or equivalent specifications; see Annex C).
4.3 Construction
4.3.1 General
The hose assembly shall consist of:
⎯ a seamless PTFE inner tube (see 4.3.2),
⎯ corrosion-resistant steel wire reinforcement (see 4.3.3), and
⎯ corrosion-resistant steel, nickel alloy and/or titanium end fittings (see 4.3.4),
as required to meet the construction and performance requirements laid down in this International Standard
and as required for its intended use.
4.3.2 Inner tube
The inner tube shall be of a seamless construction of PTFE resin of uniform gauge; it shall have a smooth
bore and shall be free from pitting and projections on the inner surface. Additives may be included in the
compound from which the tube is extruded with no more than 2 % of such additives being retained in the
mixture.
4.3.3 Reinforcement
The reinforcement shall consist of corrosion-resistant steel wire conforming to the applicable specifications
given in 4.2.2. The wires shall be arranged over the inner tube so as to provide sufficient strength to ensure
compliance with the requirements laid down in this International Standard.
Broken or missing reinforcing wires shall be cause for rejection; crossed-over reinforcing wires shall not be
cause for rejection of the flexible hose assembly.
4.3.4 Fittings
4.3.4.1 General
It shall be proven that all fittings comply with the requirements laid down in this International Standard.
4.3.4.2 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 nickel alloy tubing, or titanium. Welded and redrawn tubing (materials 8 and 9; see Annex C)
may be used.

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ISO 8913:2006(E)
Table 1 — Metals to be used in hose assemblies
Material no.
Form Metal
(see Annex C)
Austenitic, annealed or as-rolled, corrosion-resistant steel 1
Austenitic, annealed or as-rolled, stabilized, corrosion-resistant steel 2 to 4
Bars
and Precipitation-hardening, corrosion-resistant steel 5 to 8
forgings
Titanium 6Al-4V 9
Nickel alloy type 625 10
Austenitic, seamless or welded, annealed, corrosion-resistant steel 11
Austenitic, seamless or welded, stabilized, corrosion-resistant steel 12 and 13
Tubing
Austenitic, welded and drawn, high-pressure, corrosion-resistant steel 14
Cold-worked, stress-relieved, titanium alloy 15
Nickel alloy, type 625, seamless or welded, annealed 16
Wire Austenitic, cold-drawn, corrosion-resistant steel 17 to 20

4.3.4.3 End fitting collars (sockets)
All end fitting collars (sockets), crimped or swaged, fabricated from type 304 stainless steel, shall be capable
of passing an embrittlement test as specified in ASTM A262, practice E, prior to assembly to the fitting and
subsequent crimp or swaging operation. Collars (sockets) fabricated from stabilized austenitic steel
(Type 304L, 321 or 347) are acceptable without being subjected to the embrittlement test.
4.4 Inner tube
4.4.1 Density and relative density
3
The density of the hose inner tube shall not exceed 2,155 g/cm when tested in accordance with
3
ISO 7258:1984, either method A or method B. The relative density shall not exceed 2,204 g/cm when tested
in accordance with ISO 7258:1984, method C.
4.4.2 Tensile strength
When tested in accordance with ISO 8829:1990, 4.2, the longitudinal tensile strength for all tube sizes shall be
at least 15,1 MPa (2 200 psi).
When tested in accordance with ISO 8829:1990, 4.2, the transverse tensile strength for sizes DN16 (−10) and
larger shall be at least 12,4 MPa (1 800 psi); for sizes under DN16 (−10), the transverse strength need not be
tested.
4.4.3 Elongation
When tested in accordance with ISO 8829:1990, 4.2, the elongation shall be at least 200 %.
4.4.4 Tube roll
The tube shall not leak, split, burst or show any signs of malfunction, when tested through the sequence as
specified in ISO 8829:1990, 4.3.2.
4.4.5 Tube proof pressure
After being subjected to the tube roll test sequence (see 4.4.4), the tube, without reinforcing wires, shall not
leak, burst or show any signs of malfunction, when tested as specified in ISO 8829:1990, 4.3.3.
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ISO 8913:2006(E)
4.4.6 Electrical conductivity
When tested in accordance with ISO 8829:1990, 4.4, the electrical current shall be equal to or greater than
a) 6 µA for sizes DN06 to DN12 (inclusive) (−04 to −08);
b) 12 µA for sizes DN16 (−10) and over.
4.5 Hose
4.5.1 Dimensional requirements
The hose assembly dimensions, except for length, shall be as specified in Figure 1 and Table 2A or 2B.

a
See footnote b to Table 2a or 2b.
Figure 1 — Hose and fitting dimensions

Table 2a — Hose and fitting dimensions as shown in Figure 1 — Imperial units
Dimensions in inches
Hose (braided) Fitting Spherical ball size
Attachment Wall thickness
for hose
Hose
Inside Outside Inside Outside
length of inner tube assembly inside
b
size a
diameter diameter diameter diameter
diameter
l δ
d D d D
h h f f
Straight Elbow
(nom.) min. min. max. min. max. max. min. max. fittings fittings
04 0,212 0,360 0,390 0,135 0,690 0,98 0,035 0,046 0,122 0,115
06 0,298 0,455 0,490 0,240 0,800 1,09 0,035 0,046 0,216 0,204
08 0,391 0,585 0,615 0,340 0,970 1,33 0,040 0,051 0,306 0,289
10 0,485 0,690 0,730 0,410 1,100 1,36 0,045 0,056 0,369 0,349
12 0,602 0,950 0,990 0,508 1,380 1,40 0,045 0,056 0,459 0,434
16 0,852 1,230 1,270 0,760 1,660 1,60 0,045 0,056 0,684 0,646
a
Minimum specified inside diameter shall be verified by passing a spherical ball through the hose assembly (see 4.5.3)
b
Width across corners of nut and socket hexagon may exceed the values given for D .
f

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ISO 8913:2006(E)
Table 2b — Hose and fitting dimensions as shown in Figure 1 — SI units
Dimensions in millimetres
Hose (braided) Fitting Spherical ball size
Attachment Wall thickness for hose
Hose
Inside Outside Inside Outside
length of inner tube
assembly inside
b
size a
diameter diameter diameter diameter
diameter
l δ
d D d D
h h f f
Straight Elbow
(nom.) min. min. max. min. max. max. min. max. fittings fittings
DN06 5,4 9,1 9,9 3,4 17,5 24,9 0,9 1,2 3,1 2,9
DN10 7,6 11,6 12,4 6,1 20,3 27,7 0,9 1,2 5,5 5,2
DN12 9,9 14,9 15,6 8,6 24,6 33,8 1 1,3 7,7 7,3
DN16
12,3 17,5 18,5 10,4 28 34,5 1,1 1,4 9,4 8,8
DN20
15,3 24,1 25,1 12,9 35 35,6 1,1 1,4 11,7 11
DN25 21,6 31,2 32,3 19,3 42,2 40,6 1,1 1,4 17,4 16,4
a
Minimum specified inside diameter shall be verified by passing a spherical ball through the hose assembly (see 4.5.3)
b
Width across corners of nut and socket hexagon may exceed the values given for D .
f

4.5.2 Physical requirements
The hose assemblies shall comply with the physical and weight/linear density requirements specified in
Table 3.
Table 3 — Physical requirements of hose assemblies and linear density (weight) of hose
Linear density (weight) Bend radius
Hose size Volumetric expansion
a
of hose at inside of bend
(nom.) max.
max. min.
3
SI Imperial kg/mm (lb/in) mm (in) ml/m (cm /in)
DN06 04 0,17 (0,009)  38 (1,50)  2,6 (0,065)
DN10 06 0,27 (0,015)  63 (2,50)  3,4 (0,085)
DN12 08 0,36 (0,020)  73 (2,88)  5,3 (0,135)
DN16 10
0,48 (0,027)  82 (3,25)  8,7 (0,220)
DN20 12 0,98 (0,058) 101 (4,00) 11,8 (0,300)
DN25 16 1,52 (0,085) 127 (5,00) 29,5 (0,750)
a
The linear density (weight) of the hose shall be determined on a minimum length of 300 mm (12 in), as applicable.

4.5.3 Bore check
The hose assembly shall permit the free passage of a solid rigid sphere throughout its length. See Table 2a or
2b as applicable.

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ISO 8913:2006(E)
4.5.4 Assembly length
Tolerances on hose assembly lengths shall be as specified in 4.5.4.1 and 4.5.4.2, unless otherwise specified.
4.5.4.1 Imperial (inch) units (Type A)
a) ± 0,125 in for lengths under 18 in.
b) ± 0,250 in for lengths from 18 in to 36 in exclusive.
c) ± 0,500 in for lengths from 36 in to 50 in exclusive.
d) ± 1 % for lengths of 50 in and over.
4.5.4.2 SI (metric) units (Type B)
a) ± 5 mm for lengths under 500 mm.
b) ± 10 mm for lengths from 500 mm to 1 000 mm exclusive.
c) ± 15 mm for lengths from 1 000 mm to 1 500 mm exclusive.
d) ± 1 % for lengths of 1 500 mm and over.
4.6 Screw threads
Unless otherwise specified (see 4.3.4), fitting threads shall be in accordance with ISO 3161 for imperial (inch)
fittings and ISO 5855-3 for SI (metric) fittings. A 10 % increase in the tolerance of the fitting thread of the nut
during assembly and testing shall not be cause for rejection of the hose assembly.
4.7 Part numbering of interchangeable parts
All parts complying with this International Standard and having the same manufacturer’s or standard's part
number shall be functionally and dimensionally interchangeable.
4.8 Identification of products
4.8.1 General
The hose assembly and its component parts shall be permanently marked.
4.8.2 Fittings
The manufacturer’s name or trademark shall be permanently marked on one element of all end fittings.

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ISO 8913:2006(E)
4.8.3 Hose assembly
A permanent marking shall be applied on a fitting or on a permanent band or bands securely attached to the
hose. Bands shall be no wider than 25 mm (1 in) and shall not impair the flexibility or the performance of the
hose. Unless otherwise specified, the marking on the fitting or band shall include the following information:
a) the hose assembly manufacturer’s name or trademark (optional);
b) ISO 8913 type A or type B, as applicable;
c) the hose assembly manufacturer’s CAGE/NATO code;
d) the complete hose assembly part number;
e) the nominal pressure “21 000 kPa” or “3 000 psi”, as applicable;
f) the operating temperature “204 °C” or “400 °F”, as applicable;
g) the pressure test symbol “PT”;
h) the date of hose assembly manufacture, expressed in terms of month and year or batch number;
i) fire resistance type according to ISO 2685, SAE AS1055 or SAE AS150, when applicable.
4.9 Workmanship
4.9.1 General
Workmanship shall be of such quality as to ensure that hose assemblies furnished under this specification 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.
4.9.2 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.
4.9.3 Cleaning
All hose assemblies shall be free from oil, grease, dirt or other foreign materials, both internally and externally.
4.10 Hose assembly — Test and performance requirements
4.10.1 Proof pressure
When tested in accordance with ISO 8829:1990, 5.8, each hose assembly shall withstand the proof pressure
specified in Table 4a or 4b, as applicable, without malfunction or leakage.
4.10.2 Elongation and contraction
When test specimens of the sample hose assemblies are tested in accordance with ISO 8829:1990, 5.5, there
shall be no more than a ± 2 % change in length in a 250 mm (10 in) gauge length.
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ISO 8913:2006(E)
Table 4a — Pressure requirements for Type A hose assemblies — Imperial units
Burst pressure
Hose Operating Proof
Room temperature High temperature
size pressure pressure
min. min.
(nom.) psi (kPa) psi (kPa) psi (kPa) psi (kPa)
16 000 12 000
04
(110 320) (82 740)
06
14 000 10 500
(96 530) (72 400)
3 000 6 000
08
(20 685) (41 368)
10
12 000 9 000
12
(82 740) (62 055)
16

Table 4b — Pressure requirements for Type B hose assemblies — SI units
Burst pressure
Hose Operating Proof
Room temperature High temperature
size pressure pressure
min. min.
(nom.) kPa (psi) kPa (psi) kPa (psi) kPa (psi)
DN06
DN10
DN12
21 000 42 000 84 000 63 000
(3 046) (6 091) (12 183) (9 137)
DN16
DN20
DN25

4.10.3 Volumetric expansion
When test specimens of the sample hose assemblies are tested in accordance with ISO 8829:1990, 5.6, the
volumetric expansion shall not exceed the limits specified in Table 3, as applicable.
4.10.4 Leakage
When test specimens of the sample hose assemblies are tested in accordance with ISO 8829:1990, 5.7, there
shall be no leakage.
4.10.5 Thermal shock and burst at high temperature
4.10.5.1 Preconditioning
Two test specimens of the sample hose assemblies shall be tested: one test specimen shall be air-aged
(see 5.5.6.2) and the other shall be unaged (see 5.5.6.3).
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ISO 8913:2006(E)
4.10.5.2 Requirement
When tested in accordance with ISO 8829:1990, 5.17, 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 4a or 4b, as applicable, the samples shall be deemed to have failed.
4.10.6 Impulse
4.10.6.1 Preconditioning
Six 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-aged, two air-aged and two unaged (see 5.5.6).
After this initial preconditioning, subject the test specimens at room temperature to the proof pressure
specified in Table 4a or 4b, as applicable, for at least 5 min. Then pressurize the test specimens to
21 000 kPa or 3 000 psi, as applicable. While maintaining this pressure at room temperature, immerse the test
specimens in a 35 g/l ± 1 g/l sodium chloride solution — the sodium chloride solution shall contain a dry basis
containing mass fractions of not more than 0,1 % sodium iodide and 0,5 % total impurities — for 8 min to
10 min. Allow to dry in air for the remainder of 1 h. Repeat this subsequent immersion and air-drying process
no fewer than 50 times.
4.10.6.2 Requirement
When tested in accordance with ISO 8829:1990, 5.10 (i.e. in accordance with ISO 6772), the sample hose
assemblies shall comply with the test requirements without any signs of leakage [see also 7 h)].
Size DN20 (12) and larger may be bent in a 90° configuration, in lieu of 180° as defined in
ISO 8829:1990, 5.10, at a reduced length as noted in Table 5a or 5b, as applicable, to reduce fluid volume.
Table 5a — Length of test specimens — Imperial units
Dimensions in inches
Length of test specimens
for impulse tests for flexure tests for electrical for fire resistance for other tests
Hose
(4.10.6) (4.10.7) conductivity test (4.10.14)
(six specimens,
size
(4.10.13)
(six specimens, (two specimens, (three specimens, nos. 3 to 6
nos. 7 to 12) nos. 1 and 2) (one specimen, nos. 16 to 18) and
no. 15) nos. 13 and 14)
04 12 16
06 15 19
One sample for
each size with a
08 18 21
specimen length 27 18
10 21 23 as specified in
ISO 8829-2
a
12 25 (18) 27
a
16 31 (23) 32
a
Value in parentheses is the reduced assembly length if testi
...

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