Section
11 High strength steel for special marine applications
11.1 Goal-based framework
11.1.1 The purpose of this Section is to present a goal-based approach to the requirements
for high strength steel for special marine applications, not covered elsewhere in
the Rules for the Manufacture, Testing and Certification of Materials, July 2022. Whilst the primary intent of the
application of the material listed herein is for pressure vessels/submersible craft
intended for human occupancy, use and application of this material for other
constructions may be specially considered within the scope of the goal-based
framework.
11.1.2 The goals, functional requirements and performance requirements listed herein relate
to the manufacture and testing of applicable base materials.
11.1.3 In addition to this goal-based framework, the relevant requirements of the Rules for the Manufacture, Testing and Certification of Materials, July 2022 are to be complied with to achieve certification. In
order to satisfy the goal-based framework in this Chapter, it is also necessary to
comply with the applicable Rules related to materials, manufacture, testing, survey
and classification.
11.1.4 The list of goals is as follows:
- The material shall withstand the applied design loads and
integrity requirements for minimising the risk of loss of the structure due to
failure.
- The material for components, products and systems shall
minimise the hazard to persons, assets or environment in any foreseeable
operating conditions.
11.1.5 The list of functional requirements (FR) is as follows:
- The material shall be manufactured and finished so as to
provide assurance that the appropriate quality and mechanical property
requirements are achieved.
- The material shall be weldable.
- The material shall function in a safe and acceptable manner,
for compliance with manufacturing and design criteria.
11.1.6 The list of performance requirements (PR) is as follows:
- The material shall have the mechanical properties, for
Material Class (Special Application), as specified in Table 3.11.1 Essential mechanical
properties for Material Class Special Applications 1 and 2, and any other
project requirements.
- The material shall have the chemical composition for the
appropriate Material Class (Special Application 1 or 2), as specified in Table 3.11.2 Chemical composition for
Material Class Special Applications 1 and 2, and any other project
requirements.
- The material shall demonstrate the ability to:
- Withstand explosive loading, when applicable.
- Meet suitable toughness requirements as required by
the application and by the specified testing regime.
- Withstand tensile loads under the specified
operating conditions and meet the requirements of a specified testing
regime.
- Be suitably ductile for loads under the specified
operating conditions and meet the requirements of a specified testing
regime.
- Meet specified identification, dimensional and
quality requirements.
- All material shall be in the quenched and tempered supply
condition or be subject to alternative rolling and heat treatment parameters
according to the approved manufacturing specification in order to achieve the
required mechanical properties.
- The weldability of the material shall be confirmed by either
an evidence-based regime according to a recognised method, or by a
performance-based regime, agreed with LR:
- The maximum carbon equivalent value (CEV), when
calculated using UK Defence Standards criteria, shall be as specified in
Table 3.11.3, Carbon equivalent values for Material Class Special
Applications 1 and 2.).
- The maximum CEV values, when calculated using LR
Rules, shall be as per the values of H55QT or H69QT (for Material Class
Special Applications 1 and 2 respectively), within Table 3.10.3 Maximum Ceq, CET and Pcm values.
- A typical tensile strength value will be in the range of
640-820 N/mm2, for Material Class Special Application 1.
- A typical tensile strength value will be in the range of 725-860 N/mm2, for
Material Class Special Application 2.
Table 3.11.1 Essential mechanical
properties for Material Class Special Applications 1 and 2
| Material
Class (Special Application) (see Note 1)
|
Yield strength (or 0,2% proof strength) (minimum)
N/mm2
|
Elongation
(minimum) %
|
Charpy value
J (minimum)
|
Charpy test
temperature °C
|
Hardness
value (HB)
|
| High
Strength Steel – Special Application 1
|
550
|
20
|
80
|
−80
|
207 -
248
|
| High
Strength Steel – Special Application 2
|
690
|
18
|
80
|
−80
|
|
|
|
|
|
For
thickness >60mm
|
|
228 -
270
|
|
|
|
|
70
|
−80
|
|
Note 1. In addition to the above performance requirements for
essential mechanical properties (for Material Class Special
Applications 1 and 2), the following tables provide further
details for tensile, hardness, and Charpy impact requirements,
should the LR accepted solution route be followed.
|
Table 3.11.2 Chemical composition for
Material Class Special Applications 1 and 2
|
Material Class (Special Application)
|
| Material grade chemical composition
|
High
Strength Steel – Special Application 1
|
High Strength Steel – Special Application
2
|
| Element (%) by weight
|
| All thickness ranges
(see Note 1)
|
Plate Thickness (mm)
|
| 6 to 32
inclusive
(see Note 5)
|
Over 32 to
76
(see Note 5)
|
Over 76 to
140
(see Note 5)
|
| Carbon
|
≤0,18
|
0,10 –
0,18
|
0,14 – 0,20
|
0,14 –
0,20
|
| Manganese
|
0,10–0,40
|
0,10 –
0,40
|
0,10 – 0,40
|
0,10 –
0,40
|
| Aluminium
(see Note 2)
|
0,015–0,060
|
0,015 –
0,060
|
0,015 – 0,060
|
0,015 –
0,060
|
| Phosphorus
(see Note 3)
|
≤0,015
|
0,015
|
0,015
|
0,015
|
| Sulphur
|
≤0,008
|
0,004
|
0,004
|
0,004
|
| Silicon
|
0,15–0,35
|
0,15 –
0,38
|
0,15 – 0,38
|
0,15 –
0,38
|
| Nickel
|
2,25–3,25
|
2,25 –
3,50
|
2,75 – 3,50
|
3,00 –
3,50
|
| Chromium
|
1,00–1,80
|
1,00 –
1,80
|
1,40 – 1,80
|
1,50 –
1,90
|
| Molybdenum
|
0,2–0,6
|
0,20 –
0,60
|
0,35 – 0,60
|
0,50 –
0,65
|
| Nitrogen (see Note 2)
|
≤0,012
|
0,010
|
0,010
|
0,010
|
| Residual
elements
|
|
|
|
|
| Titanium
|
≤0,020
|
0,02
|
0,02
|
0,02
|
| Vanadium
|
≤0,020
|
0,03
|
0,03
|
0,03
|
| Copper
|
≤0,20
|
0,25
|
0,25
|
0,25
|
| Arsenic
|
≤0,03
|
0,025
|
0,025
|
0,025
|
| Antimony
|
≤0,010
|
0,025
|
0,025
|
0,025
|
| Lead
|
≤0,005
|
Not
specified
|
Not
specified
|
Not
specified
|
| Tin
|
≤0,02
|
0,030
|
0,030
|
0,030
|
| Cobalt (see
Note 4)
|
≤0,03
|
0,030
|
0,030
|
0,030
|
|
Note 1. The listed product percentage by weight values also apply
to ladle percentage weight values, with the exception of
sulphur, where the maximum percentage weight value is
≤0,006.
Note 2. The steel is to be fully killed, using aluminium fine grain
practice, with a minimum aluminium content of 0,015 per cent and
greater than twice the percentage nitrogen.
Note 3. Where plates are specified as subject to stress relief,
the preferred maximum phosphorus content is 0,010 per cent and
is not to exceed 0,012 per cent.
Note 4. For Naval submersible craft with nuclear propulsion, and
where the project authority requires, each castis to be analysed
for cobalt. Where the content exceeds 0,030 per cent,
instructions are to be obtained from the project authority
before release of the product. For commercial submersible craft,
there is no requirement for cobalt content analysis.
Note 5. Single values are maximum percentages. These elements
should not be added deliberately.
|
11.2 LR accepted solutions for high strength steel for special marine applications
11.2.1 Provision is made in this Section for weldable high strength steels
intended for use in special marine applications, which are not covered elsewhere in
this Chapter.
11.2.3 The application, in entirety, of the prescriptive content in this Section (including
any references leading out) is considered to meet the listed goals.
11.2.5 The requirements presented herein represent an accepted material solution
to meet the requirements of High Strength Steel – Special Application 1 and Special
Application 2, of which Q1(N) and HY100 (UK) grades of rolled plate are respective
examples.
11.3 General requirements
11.3.2 Supplied High Strength Steel – Special Application 1plate product is to
be in the thickness range 6,00 mm to 150 mm.
11.3.3 Supplied High Strength Steel – Special Application 2 plate product is to be in the
thickness range 6,00 mm to 140 mm.
11.4 Manufacture and chemical composition
11.4.1 All plate products are to be produced by LR approved steelmaking
processes, and any specific requirements for casting type shall be specified by the
project.
11.4.3 Carbon equivalent is to be calculated using the following formula, and
the results compliant with the values listed in Table 3.11.3 Carbon equivalent values
for Material Class Special Applications 1 and 2:
Note This CEV
formula is only to be used for High Strength Steel – Special Application class
steels. Other references to CEV formulae within LR Rules are not applicable to
High Strength Steel – Special Application class steels. Similarly, this formula
shall not be used to determine CEV for any other steel or product contained in
other Rules, Chapters or Sections not related specifically to High Strength
Steel – Special Application 1 or Special Application 2 class steel.
Table 3.11.3 Carbon equivalent values
for Material Class Special Applications 1 and 2
| High Strength Steel – Special Application
1
|
High Strength Steel – Special
Application 2
|
| Plate thickness (mm)
|
Carbon equivalent values
|
Plate thickness (mm)
|
Carbon equivalent values
|
| Target
|
Maximum
|
| 6 – 30
mm
|
0,62
|
0,64
|
All thickness ranges
|
0,75 max
|
| 30,1 – 150
mm
|
0,66
|
0,70
|
11.5 Heat treatment
11.5.1 Plates are to be supplied in the quenched and tempered condition with
the following specific requirements:
- (a) For Special Application 1, the plates shall be hardened by
heating above the upper critical temperature, but not to more than 950°C,
followed by water spray quenching. Subsequent quenching shall be in the
range 600°C to 675°C. Heat treatment records are to be supplied for each
batch. Pickling or flame descaling is not permitted after heat treatment.
- For Special Application 2, the manufacturer may determine the detailed
procedure to produce plates meeting the mechanical property requirements
with the exception that the final tempering temperature is to be in the
range 660°C to 680°C. Plates, after receiving tempering and heat treatment,
shall be cooled at a rate equal to or faster than air cooling.
11.5.2 Heat treatment, quenching and tempering operations are to be undertaken under
controlled conditions. Furnaces are to be thermally monitored (including temperature
uniformity) and calibrated to an appropriate International Standard.
11.6 Cleanliness
11.6.1 Plates are to be subject to inclusion content assessment in accordance
with ASTM E45 (latest edition) requirements, as outlined in Table 3.11.4 Cleanliness
requirements.
Table 3.11.4 Cleanliness
requirements
| Worst field (as per ASTM
E45)
|
Total fields see Notes 1 and 2
|
| Type see Note 3
|
Severity level see Note 3
|
B + C + D ≤ 25
|
| B, C, D (according to JK inclusion rating)
|
≤
2
|
|
Note 1. The presence
of any silicate material is not acceptable.
Note 2. Equivalent
inclusion types to ASTM E45 may be used, as defined in standard
EN 10247 (i.e. EB, EC, ED)
Note 3. Nomenclature
relates to inclusion type and severity. Inclusion type and
severity level terminology as stated in ASTM E45 (latest
edition).
|
11.6.2 Material is to exhibit homogeneous microstructure throughout the section thickness
and be free from macro segregation.
11.7 Dimensions, flatness, thickness and weight control
11.7.1 Plates are to be supplied to nominal dimensions as required in Table 3.11.5 Dimensional tolerances for
Material Class Special Applications 1 and 2.
Table 3.11.5 Dimensional tolerances for
Material Class Special Applications 1 and 2
| Tolerance on length and width of plate for
Special application 1
|
| Length of plate
|
Tolerance
|
| Minus
|
Plus
|
| Up to and
including 3000 mm
|
0
|
13
mm
|
| Over 3000 mm
up to and including 6000 mm
|
0
|
25
mm
|
| Over 6000
mm
|
0
|
32
mm
|
| Tolerance on length and width of plate for
Special application 2
|
| Thickness of plate
|
Tolerance
|
| Minus
|
Plus
|
| Up to and
including 51 mm
|
6 mm
|
19
mm
|
| Over 51 mm
thick up to and including 102 mm
|
6 mm
|
25
mm
|
| Over 102
mm
|
6 mm
|
29
mm
|
11.7.2 Plates are to comply with the flatness tolerances in Table 3.11.6 Flatness tolerance for plate
and measurement information for Special Application 1 and Table 3.11.7 Flatness tolerance for plate
and measurement information for Special Application 2.
Table 3.11.6 Flatness tolerance for plate
and measurement information for Special Application 1
| Thickness
|
Flatness
tolerance
|
| Less than or
equal to 12 mm
|
10
mm/metre
|
| Greater than
12 mm but less than or equal to 150 mm
|
6
mm/metre
|
| Method of
measurement
|
(a) If the
pitch of waviness is less than 1 m, the measurement should be made
by a 1 m straight edge across affected edges.
(b) If the pitch of
waviness is greater than 1 m, the measurement should be made by
a 2 m straight edge across the affected edges.
|
Table 3.11.7 Flatness tolerance for plate
and measurement information for Special Application 2
| Thickness (mm)
|
Flatness Tolerances for specified
widths (mm) (see Notes 1, 2 and 3)
|
|
Up to
900
|
900 to 1,200
|
1,200 to 1,500
|
1,500 to 1,800
|
1,800 to 2,100
|
2,100 to 2,400
|
2,400 to 2,700
|
2,700 to 3,000
|
3,000 to 3,600
|
Over 3,600
|
| 6
to 10
|
19
|
24
|
29
|
35
|
44
|
48
|
51
|
57
|
60
|
-
|
| Over 10 up to 13
|
19
|
22
|
24
|
24
|
29
|
33
|
38
|
41
|
48
|
70
|
| Over 13 up to 19
|
16
|
19
|
22
|
22
|
25
|
29
|
32
|
35
|
41
|
57
|
| Over 19 up to 25
|
16
|
19
|
22
|
22
|
24
|
25
|
29
|
33
|
38
|
51
|
| Over 25 up to 51
|
14
|
16
|
19
|
21
|
22
|
24
|
25
|
25
|
25
|
41
|
| Over 51 up to 102
|
13
|
14
|
18
|
19
|
19
|
19
|
19
|
22
|
25
|
32
|
| Over 102 up to 140
|
14
|
18
|
19
|
19
|
22
|
22
|
24
|
29
|
32
|
32
|
| Measurement
|
The flatness as specified in the
table is to be an overall flatness factor. This factor is not to
apply to 'kinks' or 'waviness'. The waviness or kinking permitted is
to be evaluated by laying a one metre straight edge across the
affected edges. The maximum permissible deviation from the straight
edge is 6,5 mm.
|
|
Note 1. Flatness
tolerances for length and width. The longer dimension specified
is considered the length and variations from a flat surface
along the length are not to exceed the tabular amount for the
specified width in any 4,0 metres of length.
Note 2. When the
longer dimension is under 1 metre, the variation in flatness is
not to exceed 6 mm.
Note 3. The above
table and notes cover the flatness tolerances of circular and
sketch plates, based on the maximum dimensions of those
plates.
|
11.7.4 Thickness gauging may be taken by the use of calibrated mechanical or
ultrasonic instruments, with the following grid sections to be applied:
- For undressed plates, grid lines are to be marked 25 mm from each
edge and end, thereafter at intervals of 600 mm x 600 mm grid squares.
- For dressed areas, the grid size is reduced to 150 mm x 150 mm for
plates up to and including 12 mm thick, and 300 mm x 300 mm for plates over 12
mm thick.
Table 3.11.8 Tolerances for thickness and
weight control for Special Application 1
| Item
|
Plate thickness
(mm)
|
Tolerances
|
| Thickness
|
Maximum weight
|
| Bulk orders
|
Small
orders or individual
plates
|
| Individual
plates
|
Batch
|
| A
|
6,1–12
|
+2% −7%
|
+2%
|
+0
|
+2%
|
| B
|
12,1–25
|
+1% −3%
|
+1%
|
+0
|
+1%
|
| C
|
25,1 and over
|
+1% −3%
|
+1%
|
+0
|
0
|
| D
|
Plates for insert pads
|
+5% -0
|
Not applicable
|
Not applicable
|
Not applicable
|
|
Note 1. Where
required by the project requirements, plates are to be weighed
after final heat treatment with any surface dressing and
abrasive blasting completed. Scale accuracy should be ±1,0 per
cent of the nominal weight of subject plate.
|
Table 3.11.9 Tolerances for thickness
and weight control for Special Application 2
| Item
|
Nominal Plate Thickness
(mm)
|
Thickness
Tolerance
|
| A
|
6 to 25 inclusive
|
+0,75 mm - 0,25 mm
|
| B
|
Over 25,1 up to and
including 75
|
+3% - 0,25 mm
|
| C
|
Over 75
|
+2,25 mm - 0,25 mm
|
|
Note 1. Where
required by the project requirements, plates are to be
weighed after final heat treatment with any necessary
dressing of the surface and abrasive blasting completed. The
machine accuracy should be ±1,0 per cent of the nominal
weight of subject plate.
|
11.7.5 Weld repairs of plate defects are not permitted for either Special Application 1 or
Special Application 2.
11.8 Surface preparation and priming
11.8.1 All plates shall be abrasively blasted in accordance with specific project
requirements.
11.8.2 To avoid flash rusting and surface contamination following abrasive blasting, the
steel shall be immediately coated with a prefabrication primer in accordance with
the recommendations of the coating manufacturer.
11.8.3 Prefabrication primers shall be of a type specified by the project and approved by
LR.
11.9 Mechanical tests
11.9.2 When required for Special Application 1, through thickness tensile requirements
(sampling, testing and acceptance criteria) are to be defined by the project
requirements which should, as a minimum, conform to EN 10164, and quality class Z35.
For Special Application 2 through thickness tensile requirements are to be in
accordance with Table 3.11.10 Mechanical test
samples.
Table 3.11.10 Mechanical test
samples
| Dimensions
|
Samples required
|
| Plates over 3000 mm in
length
|
Tensile – as per Figure 3.11.1 Location of test pieces for
mechanical testing, chemical analysis and metallography.
Charpy – as per
Figure 3.11.1 Location of test pieces for
mechanical testing, chemical analysis and metallography.
Samples acquired from both plate ends.
Hardness – test at diagonally opposite corners.
Through thickness tensile (where required) - as per
Figure 3.11.1 Location of test pieces for
mechanical testing, chemical analysis and metallography.
|
| Plates under 3000 mm in
length
|
Tensile – as per Figure 3.11.1 Location of test pieces for
mechanical testing, chemical analysis and metallography.
Charpy – as per
Figure 3.11.1 Location of test pieces for
mechanical testing, chemical analysis and metallography.
Samples acquired from one plate end only.
Hardness – test at diagonally opposite corners.
Through thickness tensile (where required) - as per
Figure 3.11.1 Location of test pieces for
mechanical testing, chemical analysis and metallography.
|
| Notes: Through thickness
tensile
|
- For all plate material equal or greater than 30 mm thick,
full thickness short transverse tensile tests are to be
taken from the first plate of the cast (top end) to assess
through thickness ductility (according to EN 10164).
- Samples are to be taken from the positions
shown in Figure 3.11.1 Location of test pieces for
mechanical testing, chemical analysis and metallography. For
non-extension pieces these are to be as per EN 10164:
The test piece shall have the following
diameter, do:
do = 6 mm or 10 mm for 20 ≤
t ≤ 40, where t is the plate thickness
in mm;
do = 10 mm
for 40 < t ≤ 400, where t is the plate
thickness in mm.
- The acceptance criteria are to Quality Class Z35, as per EN
10164.
|
| Notes: Tensile
|
- Tensile test specimens are to be in
accordance with ISO 6892-1: Metallic materials – Tensile
testing – Part 1: Method of test at room
temperature.
- Test specimens circular in section of
200 mm2 cross-sectional area are to be taken from
the quarter thickness position (providing that plate
thickness is sufficient).
- For plates where 200 mm2
cross-sectional area test pieces can be taken, but not at
quarter thickness position, the axis of the test piece is to
be as close as possible to the quarter thickness
position.
- For plates which are too thin for 200
mm2 cross- sectional area test pieces to be
taken, the test pieces are to be the largest possible in
accordance with ISO 6892-1.
- Rectangular section test pieces are to
have a gauge length equal to 5,65√S0 where
S0 is the cross-sectional area of the test
piece.
|
| Notes: Charpy
|
- Charpy: Middle line of test specimens is
to coincide with mid-plate thickness.
- Charpy notch to be perpendicular to
rolled surface.
- Charpy specimens to be machined at least
1,0 mm from surface.
- Standard 10 mm x 10 mm specimens. Sub
size specimens permitted for material less than 12 mm
thickness (i.e. 10 mm x 5 mm, 10 mm x 7,5 mm).
|
| Notes: Hardness
|
- Test method ISO 6506-1: Metallic
Materials-
Brinell hardness test – Part 1: test method shall be
used.
- If hardness results are outside of
specification, batch to be investigated.
|
Figure 3.11.1 Location of test pieces for
mechanical testing, chemical analysis and metallography
11.9.3 The results of mechanical tests shall comply with the appropriate requirements given
in the following tables:
Table 3.11.11 Tensile and hardness properties for High Strength Steel for Material Class
Special Applications 1 and 2
| Material
Class
|
Thickness
|
0,2% Proof strength
(N/mm2)
(see Notes 1 and
2)
|
Elongation %
|
Reduction
in area
%
|
Hardness
HB
|
|
|
|
Min
|
Max
|
Min
|
Min
|
Range
|
| Special Application 1
|
≤16 mm
|
550
|
690
|
20
|
-
|
207– 248
|
| 16,1 mm up to 150 mm
|
550
|
655
|
20
|
55 – Longitudinal
50 – Transverse
|
207–248
|
| Special Application 2
|
<19 mm
|
690
|
825
|
18
|
-
|
228– 270
(Note 3)
|
| 19 mm up to
140 mm
|
690
|
825
|
18
|
45 –
Transverse
|
228–270
(see Note 3)
|
|
Note 1. For High Strength Steel Special Application 1, the tensile
strength is to be recorded and is to be such that the ratio of
0,2% proof strength to tensile strength for all plate thickness
is not to exceed 0,90.
Note 2. For High Strength Steel Special Application 2, the tensile
strength is to be recorded and is to be such that the ratio of
0,2% proof strength to tensile strength for plate thickness from
6 mm to less than 19 mm thick is not to exceed 0,95, and for
plate thickness 19 mm and above, the ratio is not to exceed
0,92.
Note 3. If any result is outside the range 228 HB to 270 HB, the
cause of the discrepancy between hardness and the normally
expected tensile strength shall be fully investigated by the
steel mill before the plate can be despatched from the steel
mill. The project authority and LR shall be notified of the
reasons for any discrepancy between the hardness and expected
tensile results and any ensuing mitigation actions.
|
Table 3.11.12 Charpy impact properties for High Strength Steel for Material Class Special
Applications 1 and 2
| Material
Class
|
Thickness
|
Charpy
value
J
|
Charpy
test temperature
°C
|
| Special Application 1
|
<12
mm
|
80
|
(−80)
|
|
|
|
|
|
|
65
|
(−80)
|
|
|
for a 7,5 x
10 mm sample
|
|
|
|
|
|
|
|
or
|
(−80)
|
|
|
|
|
|
|
55
|
|
|
|
(5 mm x 10
mm sample)
|
|
|
|
|
|
| ≥12 mm
(see Note 1)
|
80
|
(−80)
|
| Special Application 2
|
<12 mm
|
65
|
(−80)
|
|
|
for a 7,5 x
10 mm sample, or;
|
|
|
|
5 mm x 10 mm
sample
|
|
|
|
|
|
| 12 mm up to
60 mm (see Note 2)
|
55
|
(−80)
|
|
|
for a 10 x
10 mm sample
|
|
|
|
|
|
| >60 mm up to
140 mm (see Note 3)
|
70
|
(−80)
|
|
|
for a 10 x
10 mm sample
|
|
|
Note 1. The energy absorbed by each of the three test pieces (using
a 10 x 10 mm sample) is to be greater than 80 Joules
Note 2. The average energy absorption of the three test pieces
(using a 10 x 10 mm sample) for thicknesses up to 60 mm
inclusive at each end of the plate is to be not less than 80
joules, and no single specimen is to be less than 70
joules.
Note 3. For plates over 60 mm thick the average value is to be not
less than 70 joules, and no single value is to be less than 55
joules.
|
11.10 Identification of materials
11.10.1 Identification requirements are as follows:
- All plates are to have unique identification to enable full
traceability.
- Plates are to be identified according to any
project-specific requirements in addition to LR identification
requirements.
11.11 Additional approval testing
11.11.1 The project requirements may specify appropriate and additional
specialised testing for manufacturer approval.
11.11.2 The project specification will state the specific dynamic toughness testing
procedure, or explosion testing, as applicable.
11.11.3 The project specification will state any additional tests for manufacturer approval,
and the performance criteria and properties required.
11.12 Visual and NDE requirements
11.12.1 Visual and non-destructive examination (NDE): Surface inspection and verification of
dimensions are the responsibility of the steelmaker and shall be carried out on all
material prior to dispatch.
11.12.2 Surface discontinuities: After final heat treatment and abrasive
blasting, e.g. shot blasting, each plate is to be examined visually for surface
defects. Any surface discontinuities shall be defined as imperfections or defects,
and are to comply with project specific acceptance criteria.
11.12.3 Internal defects: Examination for internal defects shall be carried out
as required by the project specification and comply with project-specific acceptance
criteria. Where project requirements for examination of plates are not specified, LR
requires ultrasonic testing to be carried out, and the extent and acceptance
criteria shall be agreed with LR.
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