ISO/TS 24817:2006

Petroleum, petrochemical and natural gas industries - Composite repairs for pipework - Qualification and design, installation, testing and inspection

ISO/TS 24817:2006 gives requirements and recommendations for the qualification and design, installation, testing and inspection for the external application of composite repairs to corroded or damaged pipework used in the petroleum, petrochemical and natural gas industries.

Industries du pétrole, de la pétrochimie et du gaz naturel — Réparations en matériau composite pour canalisations: Conformité aux exigences de performance et conception, installation, essai et inspection

General Information

• Status: Withdrawn
• Publication Date: 05-Dec-2006
• Withdrawal Date: 05-Dec-2006
• ICS: 75.180.20 - Processing equipment
• Technical Committee: ISO/TC 67/SC 6 - Processing equipment and systems
• Drafting Committee: ISO/TC 67/SC 6 - Processing equipment and systems
• Current Stage: 9599 - Withdrawal of International Standard
• Start Date: 20-Jul-2015
• Completion Date: 13-Dec-2025

Relations

• Revised: ISO 24817:2015 - Petroleum, petrochemical and natural gas industries - Composite repairs for pipework - Qualification and design, installation, testing and inspection
• Effective Date: 09-Jul-2011

Standards Content (Sample)

TECHNICAL ISO/TS
SPECIFICATION 24817
First edition
2006-12-15
Petroleum, petrochemical and natural gas
industries — Composite repairs for
pipework — Qualification and design,
installation, testing and inspection
Industries du pétrole, de la pétrochimie et du gaz naturel — Réparations
en matériau composite pour canalisations — Conformité aux exigences
de performance et conception, installation, essai et inspection

Reference number
©
ISO 2006
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ii © ISO 2006 – All rights reserved

Contents Page
Foreword. v
Introduction . vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions. 2
4 Symbols and abbreviated terms . 5
4.1 Symbols . 5
4.2 Abbreviated terms . 8
5 Applications . 8
6 Qualification and design . 10
6.1 Risk assessment. 10
6.2 Repair class. 11
6.3 Repair lifetime . 11
6.4 Required data . 11
6.5 Design methodology . 14
6.6 Requalification . 35
7 Installation . 35
7.1 General. 35
7.2 Materials of construction . 36
7.3 Storage conditions . 36
7.4 Method statements . 36
7.5 Installer qualifications. 37
7.6 Installation guidance . 37
7.7 Live repairs. 38
7.8 Repair of clamps, piping components, tanks or vessels . 38
7.9 Environmental considerations . 38
8 Testing and inspection. 39
8.1 General. 39
8.2 Allowable defects for the repair system. 39
8.3 Repair of defects within the repair system .41
8.4 Inspection methods. 41
8.5 Repair system maintenance and replacement strategy . 41
9 System testing . 42
10 Future modifications . 42
11 Decommissioning. 42
Annex A (normative) Design data sheet . 43
Annex B (normative) Qualification data. 46
Annex C (normative) Short-term pipe spool survival test . 48
Annex D (normative) Measurement of γ for through-wall defect calculation . 50
LCL
Annex E (normative) Measurement of performance test data. 53
Annex F (normative) Measurement of impact performance . 56
Annex G (normative) Measurement of the degradation factor. 57
Annex H (informative) Axial extent of repair look-up table . 59
Annex I (normative) Installer qualification. 61
Annex J (normative) Installation requirements and guidance. 64
Bibliography . 67

iv © ISO 2006 – All rights reserved

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.
In other circumstances, particularly when there is an urgent market requirement for such documents, a
technical committee may decide to publish other types of normative document:
⎯ an ISO Publicly Available Specification (ISO/PAS) represents an agreement between technical experts in
an ISO working group and is accepted for publication if it is approved by more than 50 % of the members
of the parent committee casting a vote;
⎯ an ISO Technical Specification (ISO/TS) represents an agreement between the members of a technical
committee and is accepted for publication if it is approved by 2/3 of the members of the committee casting
a vote.
An ISO/PAS or ISO/TS is reviewed after three years in order to decide whether it will be confirmed for a
further three years, revised to become an International Standard, or withdrawn. If the ISO/PAS or ISO/TS is
confirmed, it is reviewed again after a further three years, at which time it must either be transformed into an
International Standard or be withdrawn.
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/TS 24817 was prepared by Technical Committee ISO/TC 67, Materials, equipment and offshore
structures for petroleum, petrochemical and natural gas industries, Subcommittee SC 6, Processing
equipment and systems.
Introduction
The objective of ISO/TS 24817 is to ensure that composite repairs to pipework when qualified, designed,
installed and inspected using ISO/TS 24817 will meet the specified performance requirements. Composite
repairs are designed for use in oil and natural gas industry processing and utility service applications. The
main users of this Technical Specification will be owners of the pipework, design contractors, suppliers
contracted to deliver the repairs, certifying authorities, installation contractors and maintenance contractors.

vi © ISO 2006 – All rights reserved

TECHNICAL SPECIFICATION ISO/TS 24817:2006(E)

Petroleum, petrochemical and natural gas industries —
Composite repairs for pipework — Qualification and design,
installation, testing and inspection
1 Scope
This Technical Specification gives requirements and recommendations for the qualification and design,
installation, testing and inspection for the external application of composite repairs to corroded or damaged
pipework used in the petroleum, petrochemical and natural gas industries.
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 75-3, Plastics — Determination of temperature of deflection under load — Part 3: High-strength
thermosetting laminates and long-fibre-reinforced plastics
ISO 527-1, Plastics — Determination of tensile properties — Part 1: General principles
ISO 527-4, Plastics — Determination of tensile properties — Part 4: Test conditions for isotropic and
orthotropic fibre-reinforced plastic composites
ISO 868, Plastics and ebonite — Determination of indentation hardness by means of a durometer (Shore
hardness)
ISO 10952, Plastics piping systems — Glass-reinforced thermosetting plastics (GRP) pipes and fittings —
Determination of resistance to chemical attack on the inside of a section in deflected condition
ISO 11357-2, Plastics — Differential scanning calorimetry (DSC) — Part 2: Determination of glass transition
temperature
ISO 11359-2, Plastics — Thermomechanical analysis (TMA) — Part 2: Determination of coefficient of linear
thermal expansion and glass transition temperature
ISO 14692 (all parts), Petroleum and natural gas industries — Glass-reinforced plastics (GRP) piping
ANSI/API RP 579, Recommended Practice for Fitness-for-Service
ASME B31G, Manual for Determining the Remaining Strength of Corroded Pipelines: a Supplement to B31,
Code for Pressure Piping
ASTM C581, Standard Practice for Determining Chemical Resistance of Thermosetting Resins Used in
Glass-Fibre-Reinforced Structures Intended for Liquid Service
ASTM D543, Standard Practices for Evaluating the Resistance of Plastics to Chemical Reagents
ASTM D696, Standard Test Method for Coefficient of Linear Thermal Expansion of Plastics Between − 30 °C
and 30 °C with a Vitreous Silica Dilatometer
ASTM D1598, Standard Test Method for Time-to-Failure of Plastic Pipe Under Constant Internal Pressure
ASTM D1599, Standard Test Method for Resistance to Short-Time Hydraulic Failure Pressure of Plastic Pipe,
Tubing, and Fittings
ASTM D2583, Standard Test Method for Indentation Hardness of Rigid Plastics by Means of a Barcol
Impressor
ASTM D2992, Standard Practice for Obtaining Hydrostatic or Pressure Design Basis for “Fiberglass” (Glass-
Fiber-Reinforced Thermosetting-Resin) Pipe and Fittings
ASTM D3039, Standard Test Method for Tensile Properties of Polymer Matrix Composite Materials
ASTM D3165, Standard Test Method for Strength Properties of Adhesives in Shear by Tension Loading of
Single-Lap-Joint Laminated Assemblies
ASTM D3681, Standard Test Method for Chemical Resistance of “Fiberglass” (Glass-Fiber-Reinforced
Thermosetting-Resin) Pipe in a Deflected Condition
ASTM D5379/D5379M-05, Standard Test Method for Shear Properties of Composite Materials by the
V-Notched Beam Method
ASTM D6604, Standard Practice for Glass Transition Temperatures of Hydrocarbon Resins by Differential
Scanning Calorimetry
ASTM E831, Standard Test Method for Linear Thermal Expansion of Solid Materials by Thermomechanical
Analysis
ASTM E1640, Standard Test Method for Assignment of the Glass Transition Temperature by Dynamic
Mechanical Analysis
ASTM E2092, Standard Test Method for Distortion Temperature in Three-Point Bending by
Thermomechanical Analysis
ASTM G8, Standard Test Methods for Cathodic Disbonding of Pipeline Coatings
BS 7910, Guide to methods for assessing the acceptability of flaws in metallic structures
EN 59, Glass reinforced plastics — Measurement of hardness by means of a Barcol impressor (BS 2782-10:
Method 1001, Methods of testing plastics. Glass reinforced plastics. Measurement of hardness by means of a
Barcol impressor)
EN 1465, Adhesives — Determination of tensile lap shear strength of rigid-to-rigid bonded assemblies
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
anisotropic
exhibiting different physical properties in different directions
3.2
Barcol hardness
measure of surface hardness using a surface impressor
2 © ISO 2006 – All rights reserved

3.3
composite
thermoset resin system that is reinforced by fibres
3.4
cure
curing
setting of a thermosetting resin system, such as polyester or epoxy, by an irreversible chemical reaction
3.5
delamination
separation of layers within a repair laminate or between a repair laminate and the substrate
3.6
differential scanning calorimetry
DSC
method of determining the glass transition temperature of a thermosetting resin
3.7
glass transition temperature
temperature at which a resin undergoes a marked change in physical properties
3.8
hardener
component added to a thermosetting resin to effect cure
3.9
heat distortion temperature
HDT
temperature at which a standard test bar deflects by a specified amount under a given load
3.10
in-fill material
material used to repair external surface imperfections prior to the application of the composite laminate
3.11
laminate
repair laminate
that part of a repair system that is the composite
NOTE Most composites considered in this Technical Specification are composed of discrete lamina or layers which
are wrapped or stacked one on top of the other. This stacked construction is the laminate.
3.12
leak
condition of a substrate wall that can allow the contents to make contact with, and act directly upon, the
(composite) repair laminate
NOTE This does not refer to a fluid leaking through a hole or breach in the substrate.
3.13
occasional load
load that occurs rarely and during a short time
NOTE Occasional loads typically occur less than 10 times in the life of the component and each load duration is less
than 30 min.
3.14
owner
organization that owns or operates the substrate to be repaired
3.15
pipeline
pipe with components subject to the same design conditions used to transport fluids between plants
NOTE Components may include, for example, bends, flanges, valves.
3.16
pipework
interconnected piping subject to the same set or sets of design conditions
3.17
piping
piping system
assemblies of piping components used to convey fluids within a plant
NOTE Components may include pipe, fittings, flanges, gaskets, bolting, valves. A piping system is often above
ground but sometimes buried.
3.18
ply
single wrap or layer (lamina) of a repair laminate
3.19
post cure
additional elevated-temperature cure
3.20
qualification application procedure
application procedure used to apply the repair system for the qualification tests
3.21
qualification test temperature
test temperature at which qualification testing of the repair system is performed
3.22
reinforcement
fibre embedded in the resin system
NOTE Possible fibre materials include aramid, carbon, glass, polyester or similar materials. Reinforcement results in
mechanical properties superior to those of the base resin.
3.23
repair system
system comprised of the substrate, composite material (repair laminate), filler material, adhesive and including
surface preparation and installation methods used for repair of pipework
3.24
repair system supplier
company that supplies and installs the repair system
3.25
resin system
all of the components that make up the matrix portion of a composite
NOTE Often this includes a resin, filler(s), pigment, mechanical property modifiers and catalyst or hardener.
3.26
risk
term describing an event encompassing what can happen (scenario), its likelihood (probability) and its level or
degree of damage (consequences)
4 © ISO 2006 – All rights reserved

3.27
substrate
surface on which a repair is carried out
NOTE The surface may belong to original pipework, a pipework component, pipeline, tank or vessel.
3.28
Shore hardness
measure of surface hardness using a surface impressor or durometer
3.29
thermoset resin system
resin system that cannot be resoftened following polymerization
4 Symbols and abbreviated terms
4.1 Symbols
α repair laminate thermal expansion coefficient, axial direction, expressed in millimetres per millimetre
a
degree Celsius
α thermal expansion coefficient of the repair laminate for either the axial or circumferential directions

c
α thermal expansion coefficient of substrate
s
c crack length
D external diameter
D external attachment equivalent diameter
a
D external branch, tee, nozzle diameter
b
D external diameter end dome
d
D external reducer diameter (smaller diameter)
r
d diameter (or diameter of the equivalent circle) of the through-wall defect
∆T difference between operation and installation temperatures

E tensile modulus of the composite laminate in the circumferential direction
c
E tensile modulus of the composite laminate in axial direction
a
E combined tensile modulus E E
ac
ac
E tensile modulus of substrate
s
ε circumferential design strain

c
ε allowable circumferential strain
c0
ε axial design strain
a
ε allowable axial strain
a0
ε thermal strain
t
ε short-term failure strain of the composite laminate
short
F applied axial load
ax
F equivalent axial load
eq
F applied shear load
sh
f service factor for cyclic fatigue
c
f degradation factor for the long-term performance of repairs to through-wall defects
D
f service factor for repairs to through-wall defects
leak
f service factor for performance data
perf
f repair thickness increase factor for reduced available overlap length

th,overlay
f repair thickness increase factor for piping system or vessel component

th,stress
f temperature de-rating factor for composite allowable strains
T1
f temperature de-rating factor for through-wall defect repair design
T2
φ angle subtended by axial slot
G shear modulus of the composite laminate
γ toughness parameter (energy release rate) for the composite steel interface
γ 95 % confidence limit of energy release rate
LCL
h burial depth
I second moment of area
l total axial extent of repair
l available landing area (axial extent) of undamaged substrate

available
l axial extent of design thickness of repair
over
l axial length of defect
defect
l axial length of taper
taper
N number of cycles
M applied axial moment
ax
M applied torsional moment
to
n number of observed data points
n number of wraps or layers of repair laminate
W
p design internal pressure
6 © ISO 2006 – All rights reserved

p internal pressure after repair system is applied
after
p external design pressure
e
p equivalent design pressure
eq
p external soil pressure
ext,soil
p internal pressure within the substrate during application of the repair
live
p minimum (internal pressure) load (or stress) of the load cycle
min
p maximum (internal pressure) load (or stress) of the load cycle
max
p medium-term hydrostatic test pressure
mthp
p maximum allowable working pressure (MAWP)
s
p short-term hydrostatic test pressure
sthp
p initial test pressure

p fixed linear increase in test pressure
q tensile stress
p
min
R cyclic loading severity, defined as: R =
c
c
p
max
s allowable stress of the substrate material
s measured yield stress of substrate or mill certification yield stress

a
s lower confidence limit of the long-term stress determined by performance testing
lt
T design temperature
d
T glass transition temperature
g
T maximum operating temperature of repair system
m
T ambient temperature
amb
T qualification test temperature
test
t wall thickness of substrate
t design lifetime
lifetime
t thickness of an individual wrap or layer of repair laminate
layer
t wall thickness of branch, tee
b
t wall thickness of flange
f
t design thickness of repair laminate
design
t minimum thickness of repair laminate
min
t minimum remaining substrate wall thickness
s
τ lap shear strength
ν Poisson's ratio for the repair laminate
w (axial) width of circumferential slot defect
W specific weight of soil
soilg
4.2 Abbreviated terms
ASME American Society of Mechanical Engineers
ASTM American Society for Testing and Materials
API American Petroleum Institute
AWWA American Water Works Association
BS (BSI) British Standards Institute
CFRP carbon-fibre-reinforced plastic
COSHH regulations for control of substances hazardous to health
CSWIP certification scheme for welding inspection personnel
DSC differential scanning calorimetry
FRP fibre-reinforced plastic
GRP glass-reinforced plastic
HDT heat distortion temperature
MAWP maximum allowable working pressure
MSDS materials safety data sheet
NDT non-destructive testing
OSHA Occupational Safety and Health Act
PCC post-construction committee
SMYS specified minimum yield strength
5 Applications
The qualification and design, installation, testing and inspection procedures for repair systems in this
Technical Specification cover situations involving the repair of damage commonly encountered in oil, gas and
utility pipework systems. The procedures are also applicable to the repair of pipelines, caissons, storage tanks
and vessels with appropriate consideration.
Procedures in this Technical Specification cover the repair of metallic and GRP pipework, pipework
components, pipelines originally designed in accordance with a variety of standards, including ISO 15649,
ISO 13623, ISO 14692, ASME B31.1, ASME B31.3, ASME B31.4, ASME B31.8 and BS 8010.
8 © ISO 2006 – All rights reserved

Repair systems are applied to achieve a satisfactory level of structural integrity.
The following repair situations are addressed:
⎯ external corrosion, where the defect is or is not through-wall; in this case the application of a repair
system will usually arrest further deterioration;
⎯ external damage such as dents, gouges and fretting (at supports);
⎯ internal corrosion, erosion, where the defect is or is not through-wall; in this case corrosion and/or erosion
can continue after application of a repair system, and therefore the design of the repair system shall take
this into account;
⎯ structural strengthening in local areas.
As a general guide, Table 1 summarizes the types of defect that can be repaired using repair systems.
Table 1 — Guide to generic defect types
Applicability of
Type of defect
repair system
a
General wall thinning Y
Local wall thinning Y
Pitting Y
b
Gouges R
Blisters Y
Laminations Y
Circumferential cracks Y
Longitudinal cracks R
Through-wall penetration Y
a
Y implies generally appropriate.
b
R implies can be used, but requires extra consideration.
Services that are covered within the scope of this Technical Specification include all services normally found
on an oil and gas production or processing installation. These include:
⎯ utility fluid, diesel, seawater, air;
⎯ chemicals (liquids);
⎯ production fluids, including liquid hydrocarbons, gaseous hydrocarbons and gas condensates.
The upper pressure and temperature limits are dependent on the type of damage being repaired and the type
of repair system being used. These limits are determined from the qualification testing results presented in
Clause 6.
The lower temperature limit is dependent on the type of repair laminate being used. This limit is determined by
the design requirements presented in Clause 6. The lower pressure limit, e.g. vacuum conditions, is
determined by the design requirements presented in 6.5.9.7.
The composite materials constituting the repair laminate considered within this Technical Specification are
typically those with aramid (AFRP), carbon (CFRP), glass (GRP) or polyester (or similar material)
reinforcement in a polyester, vinyl ester, epoxy or polyurethane matrix. Other fibre and matrix types are also
permissible.
6 Qualification and design
6.1 Risk assessment
A risk assessment associated with both the defect and the repair method shall be completed by the owner
prior to application of the repair system.
The following factors shall be considered within the risk assessment:
⎯ assessment of the nature and location of the defects;
⎯ design and operating conditions for the substrate and contents (including pressure, temperature, sizes
and combinations thereof);
⎯ repair lifetime (see 6.3);
⎯ geometry of the substrate being repaired;
⎯ hazards associated with system service;
⎯ availability of personnel with the necessary skills;
⎯ ease with which it is practicable to execute surface preparation operations;
⎯ performance under upset and major incident situations, including impact, abrasion, fire, explosion,
collision and environmental loading:
⎯ operational measures, including (if relevant) permits, gas testing and fire protection requirements to
ensure safety in the vicinity of the repair area;
⎯ failure modes;
⎯ inspectability (both visual and non-destructive);
⎯ repair system materials.
For clarification, the risk assessment is not intended as a means to predetermine that the repair method is the
appropriate strategy or remedial action, but rather to assess the risks associated with applying the repair
method.
The information and data describing any hazards shall be included in the method statement (7.4) to be used
on site.
Since the application of these repair systems typically changes the mode of failure from rupture of the
substrate to a leak, the consequences of failure will therefore be reduced.
The objective of the assessment shall be to establish the class of the repair (6.2), which determines the detail
of the design method (6.5) to be carried out, together with the requirements for supporting documentation.
This also determines the design margin or factor of safety to be used in the design.
Guidance on performing a risk assessment can be obtained from Reference [36].
10 © ISO 2006 – All rights reserved

6.2 Repair class
Each repair shall be allocated to a particular class following completion of the risk assessment. Repair classes
are defined in Table 2.
Class 1 repairs cover design pressures up to 1 MPa (10 bar) and design temperatures up to 40 °C and are
appropriate to the majority of the utility service systems. This class is intended for those systems that do not
relate directly to personnel safety or safety-critical systems.
Class 2 repairs cover design pressures up to 2 MPa (20 bar) and design temperatures up to 100 °C but
exclude hydrocarbons. This class is appropriate to those systems that have specific safety-related functions.
Class 3 repairs cover all fluid types and pressures up to the qualified upper pressure limit. This class is
appropriate for systems transporting produced fluids.
Applications in which the service conditions are more onerous or not included in the above, shall be
designated as Class 3.
Table 2 — Repair class
Repair class Typical service Design pressure Design temperature
Low specification duties, e.g. static head, drains, cooling
Class 1 medium, sea (service) water, diesel and other utility < 1 MPa < 40 °C
hydrocarbons
Class 2 Fire water/deluge systems < 2 MPa < 100 °C
Produced water and hydrocarbons, flammable fluids,
gas systems
Class 3 Qualified upper limit Qualified upper limit
Class 3 also covers operating conditions more onerous
than described.
6.3 Repair lifetime
The lifetime (in years) of the repair system shall be defined in the repair data sheet, Annex A. It may be limited
by the defect type and service conditions, e.g. internal corrosion.
The minimum lifetime of the repair shall be 2 years.
Short lifetimes (2 years) are intended to apply to those situations where the repair is required to survive until
the next shutdown.
Long lifetimes (up to 20 years) are intended to apply to those situations where the repair is required to
reinstate the substrate to its original design lifetime or to extend its design life for a specified period.
Once the lifetime of the repair has expired, the owner shall either remove or revalidate the repair system.
6.4 Required data
6.4.1 Background
The following data shall be supplied for each repair application. The detail to which these requirements are
fulfilled is determined by the output of the risk assessment. Original equipment design data, maintenance and
operational histories shall be provided by the owner and material qualification data shall be provided by the
repair system supplier. The availability of relevant data shall feature as part of the risk assessment.
6.4.2 Original equipment design data
Original equipment design data are required, consisting of:
a) piping line lists or other documentation showing process design conditions and a description of the piping
class, including material specification, wall thickness, and pressure and temperature ratings;
b) piping isometric drawings and, if appropriate, the output of a piping flexibility calculation;
c) specification of all operating mechanical loads not included in the above, including upset conditions;
d) original design calculations.
6.4.3 Maintenance and operational histories
Maintenance and operational histories are required, consisting of:
a) documentation of any changes in service conditions, including pressure, temperature, internal fluids and
corrosion rate;
b) past service conditions;
c) summary of all alterations and past repairs local to the substrate of concern;
d) inspection reports detailing the nature and extent of damage to be repaired.
6.4.4 Service condition data
Service condition data are required, consisting of:
a) lifetime requirements/expectation of the repair system life;
b) required design and operating pressures (internal and external)/temperatures;
c) expected future service conditions;
d) if applicable, MAWP as calculated according to the requirements of ASME B31G, API RP 579, BS 7910
or another applicable standard. This shall be carried out taking into account the current position and any
possible further degradation in the future.
An example of a design data sheet is presented in Annex A.
6.4.5 Repair system qualification data
The documentation and qualification data related to repair systems that shall be provided by suppliers are
shown in Table 3.
Details of the qualification data to be provided by the suppliers are given in Annex B.
Table 3 — Documentation and data requirements
Documentation requirement Class 1 Class 2 Class 3
Material documentation and data 9 9 9
Design capability 9 9
Surface preparation documentation 9 9 9
Short-term test data 9 9 9
Long-term test data 9 9
12 © ISO 2006 – All rights reserved

Clarification of the terms used in Table 3 is as follows:
a) Material documentation and data
This shall include a statement of the resins and reinforcements used and any standards to which they are
supplied. Basic data on material compatibility with the working environment shall also be available. It shall
be ensured that any chemical interaction between the resin (and associated curing agents) and substrate
will not cause further degradation of the substrate. Also attention shall be given to CFRP laminates and
the potential for bimetallic (galvanic) corrosion of the substrate.
b) Design capability
Suppliers who offer a repair option for Class 2 and 3 repairs shall provide design calculations with
supporting data.
c) Surface preparation
The durability of a bonded assembly under applied load is determined to a large extent by the quality of
the surface preparation used. Details of the surface preparation procedure and how it is to be
implemented shall be provided.
d) Short-term test data
These shall include tensile strength and modulus in both the hoop and axial directions and the strength of
the (adhesive) bond between the repair laminate and the substrate.
e) Long-term test data
These shall include the strength of the adhesive bond between the repair laminate and substrate and
optionally the ultimate tensile strain of the repair laminate. Long-term is defined as greater than or equal
to 1 000 h.
Table 4 lists the data required to comply with Class 3 requirements. Annex B contains the full details of the
qualification data requirements.
Table 4 — Qualification test requirements
Material property Test method
Mechanical Young's modulus ISO 527-1, ISO 527-4 (or ASTM D3039)
properties Poisson's ratio ISO 527-1, ISO 527-4 (or ASTM D3039)
Shear modulus ASTM D5379
Thermal expansion coefficient ISO 11359-2 (or ASTM D696)
Glass transition temperature of resin or heat ISO 11357-2 (or ISO 75-3, ASTM D6604,
distortion temperature of resin ASTM E1640, ASTM E831), ASTM E2092
Barcol or Shore hardness ISO 868 or EN 59 (or ASTM D2583)
Adhesion Lap shear EN 1465 (or ASTM D3165)
strength
Performance Long-term strength (optional) Annex E
data
Energy release rate (optional) Annex D
Short-term pipe spool survival test (optional) Annex C
6.5 Design methodology
6.5.1 Overview
There are two design cases.
a) Defect type A design case
The defect is within the substrate, not through-wall and not expected to become through-wall within the
lifetime of the repair system, requiring structural reinforcement only. One of the following three design
methods shall be used:
1) include allowance for the substrate (see 6.5.4);
2) exclude allowance for the substrate (see 6.5.5);
3) long-term performance test data (see 6.5.6).
b) Defect type B design case
The substrate requires structural reinforcement and sealing of through-wall defects (leaks). For substrates
with active internal corrosion, the repair laminate shall be designed on the assumption that a through-wall
defect will occur if the remaining wall thickness at the end of service life is expected to be less than 1 mm.
Both of the following design methods shall be used:
1) the design method in 6.5.7;
2) the design method for the Defect type A design case.
The greater repair thickness from the Defect type A design case or the design method in 6.5.7 shall be taken
as the repair laminate thickness, t .
design
Subclauses 6.5.9 and 6.5.10 shall be considered for each design case and applied where appropriate, with
the largest thickness being taken as the repair laminate thickness, t .
design
6.5.2 Environmental compatibility
The suitability for use of the repair system in the service environment shall be based on the following
considerations. The service environment is the environment that contacts the repair laminate. It may be either
the external or internal environment.
The qualification of the repair system (6.4.5) demonstrates that the repair system is compatible with aqueous
and hydrocarbon environments at the qualification test temperature. In general, thermoset resins are
compatible with a wide range of environments, but consideration shall be given when the environment is
strongly acidic (pH < 3,5), strongly alkaline (pH > 11) or is a strong solvent, e.g. methanol, toluene in
concentration greater than 25 %.
Resistance to UV degradation and weathering (where appropriate) shall be provided by data from the resin
supplier.
When the environmental compatibility of the repair system is unknown, then the repair system supplier shall
provide one of the following to demonstrate compatibility:
⎯ environmental compatibility data or experience of previous applications from the resin supplier,
demonstrating that the environment is no more aggressive than aqueous or hydrocarbon environments at
the design temperature;
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⎯ if no compatibility data from the resin supplier are available, then specific environmental testing is
required. One of the following test procedures – ISO 10952, ASTM D543, ASTM C581, ASTM D3681 or
equivalent – comparing the exposure of the specific environment and aqueous environment to the repair
laminate at the design temperature shall be performed. The repair system shall be considered compatible
to the specific environment if the test results from the specific environment are no worse than for the
aqueous environment.
When erosion is the cause of the degradation process of the substrate and the repair laminate is in contact
with the eroding medium, then the repair laminate can suffer material loss. The repair system supplier shall
calculate the survival of the repair system for the specified repair lifetime assuming a conservative estimate of
the loss of laminate material. Alternatively, a metal plate can be placed over the affected area prior to
application of the repair laminate to minimize material loss (of the laminate).
6.5.3 Design temperature effects
For a design temperature, T , greater than 40 °C, the repair system shall not be used at a temperature higher
d
than the glass transition temperature (T ) less 30 °C. For repair systems for which a T cannot be measured,
g g
the repair system shall not be used above the HDT less 20 °C. For repair systems which do not exhibit a clear
transition point, i.e. a significant reduction in mechanical properties at elevated temperatures, then an upper
temperature limit, T , shall be defined (or quoted) by the repair supplier.
m
For a repair system where the defect within the substrate is not through-wall, the temperature limit can be
relaxed to T less 20 °C or HDT less 15 °C. T or HDT shall be measured in accordance with Table 4.
g g
Table 5 summarizes the upper temperature limit of the repair.
Table 5 — Service temperature limits for repair systems
Defect type B limit Defect type A limit
T T
m m
T measured T − 30 °C T − 20 °C
g g g
HDT measured HDT − 20 °C HDT − 15 °C
For design temperatures u 40 °C (and Class 1 and Class 2 repairs), adequate cure of the field-applied repair
laminate or adhesive shall be demonstrated by Barcol or Shore hardness testing. For these conditions, no
acceptance criteria linked to T or HDT are stipulated. Adequate cure is defined as a measured hardness
g
value, and shall be no less than 90 % of the minimum obtained from repair system qualification in accordance
with Table 4.
The temperature de-rating factor, f , to account for elevated design temperature application used in
T1
Equation (8) is given in Table 6, where T is the upper temperature limit for the system (as defined in Table 5),
m
in degrees Celsius.
Table 6 — Temperature de-rating factor for composite allowable strains, f
T1
Design temperature Temperature factor
T f
d T1
°C
T = T 0,70
d m
T − 20 0,75
m
T − 40 0,85
m
T − 50 0,90
m
T − 60 1,00
m
...