CLASS PROGRAMME
Approval of manufacturers
DNVGL-CP-0247
Edition May 2016
Steel forgings
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DNV GL AS
FOREWORD
DNV GL class programmes contain procedural and technical requirements including acceptance
criteria for obtaining and retaining certificates for objects and organisations related to
classification.
©
DNV GL AS May 2016
Any comments may be sent by e-mail to rules@dnvgl.com
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Changes - current
CHANGES – CURRENT
This is a new document.
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Changes – current.................................................................................................. 3
Section 1 General.................................................................................................... 5
1 Objective..............................................................................................5
2 Scope and application..........................................................................5
3 Request for approval........................................................................... 6
4 References........................................................................................... 7
Section 2 Documentation requirements.................................................................. 8
1 Manufacturing summary...................................................................... 8
2 Reheating and forging......................................................................... 8
3 Cleaning and finishing......................................................................... 8
4 Heat treatment.................................................................................... 8
5 Special forging process approval for case hardened gear
transmissions (if applicable).................................................................. 8
6 Welding (if applicable)........................................................................ 9
7 Records, test facilities and procedures................................................ 9
8 Test results and records...................................................................... 9
Section 3 Approval testing.................................................................................... 11
1 Test products and testing scope........................................................ 11
2 Testing requirements.........................................................................11
Appendix A Approval coverage............................................................................. 16
1 Approval coverage of material grades and steel types.......................16
Changes – historic................................................................................................ 18
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Contents
CONTENTS
Section 1
SECTION 1 GENERAL
1 Objective
The objective of this class programme (CP) is to provide a description for which the Society bases its
approval of manufacturers intending to supply steel forgings in accordance with RU SHIP Pt.2 or other
applicable standards provided by the Society.
2 Scope and application
This programme is applicable for the approval of manufacturers of:
— Steel forgings,
as referred in the Society's rules and standards. For a description of general requirements, conditions and
procedures related to the approval, please refer to DNVGL CP 0346 which shall be applied in combination
with this programme.
This AoM programme is applicable for the approval of manufacturers of products indicated in Table 1 as per
DNV GL rules and standards.
Table 1 Range of approval:
Application areas as per RU SHIP Pt.2 Ch.2 Sec.6
RU SHIP Pt.2 Ch.2 Sec.6 [2]
Forgings for hull structures and equipment
RU SHIP Pt.2 Ch.2 Sec.6 [3]
Forgings for shafting and machinery
RU SHIP Pt.2 Ch.2 Sec.6 [4]
Forgings for crankshafts
RU SHIP Pt.2 Ch.2 Sec.6 [5]
Forgings for gearing
RU SHIP Pt.2 Ch.2 Sec.6 [6]
Forgings for boilers, pressure vessels and piping systems
RU SHIP Pt.2 Ch.2 Sec.6 [7]
Ferritic steel forgings for low temperature service
RU SHIP Pt.2 Ch.2 Sec.6 [8]
Stainless steel forgings
RU SHIP Pt.2 Ch.2 Sec.6 [9]
Bolts and nuts
Note:
Manufacture of forged chain cable accessories is not covered by this program, but need separate approval according to approval
programme DNVGL CP 0254.
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The product(s) used for approval testing (see Sec.3) will place limitations on the range of approval. The
approval will be limited to:
— each steel type group or material grade (see App.A)
— carbon and carbon-manganese (C and C-Mn) steels
— the individual alloy steels
— the individual stainless steels
— each application area, see Table 1
—
—
—
—
forging method
maximum forging weight
maximum cross section and diameter
heat treatment and delivery condition
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When applicable, specific approval will be given on the certificate for the following additional conditions:
—
—
—
—
continuous grain flow (CGF) crankshafts or crank throws; according to DNVGL CG 0037
specially approved forging process; as referred in the rules RU SHIP Pt.4 and DNVGL CG 0036
clean steel forgings; according to DNV GL rules RU SHIP Pt.2 Ch.2 Sec.6
approved steel grades for low temperature service.
The approval is limited to the material grade for which approval tests are carried out, but certain grades may
also cover other grades in the same steel type group, or the entire steel type group, as explained in App.A.
Where steel forgings are to be repaired by welding (see guidance note), or two or more items are joined by
welding to form a composite item, the manufacturer's welding shop shall either be approved for welding in
accordance with this programme, or be approved as welding workshop. For welding workshop approval, see
DNVGL CP 0352.
Guidance note:
The DNV GL rules give strict limitations for repair by welding on forgings. The limitations given by the rules shall always and without
exception be observed. Approval for repair by welding in accordance with this programme will under no circumstances give exemptions
from the relevant rule requirements.
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The manufacturer’s own heat treatment facilities shall be evaluated and approved by the Society, either
under this approval programme, or as an approved "heat-treatment workshop" based on the approval
programme DNVGL CP 0351.
Where heat treatment or case hardening is performed by a sub supplier, the sub supplier shall be approved
by the Society as a heat treatment workshop in accordance with DNVGL CP 0351.
Starting material/semi-finished steel products shall be produced at works approved by the Society.
For steel forges operates their own steel making and produce their semi-finished steel products (slabs/ingots/
etc.), the approval programme DNVGL CP 0242 shall be used to approve these facilities.
3 Request for approval
When applying for AoM, the manufacturer shall indicate the material types and grades to be covered by the
approval, including manufacturing method, dimensions, and heat treatment and delivery conditions as per
[3].
A list or table shall be provided, which shall include:
—
—
—
—
—
—
type of products
manufacturing method as part of manufacturing summary
range of applicable product sizes (dimensions and weight)
applicable steel types
heat treatment delivery conditions
reference to DNV GL rules for the applicable chemical composition, mechanical properties and heat
treatment (if applicable) or recognised standards (recognition of other standards shall be agreed in
advance)
— in case raw materials for forging (slabs/ingots/etc.) are delivered from other manufacturers: a list of raw
material suppliers and a copy of their approval certificate.
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Section 1
— the reduction ratio for the products for approval testing shall be representative for the later production of
the similar products.
Section 1
4 References
Table 2 List of references
No. Reference
Title
1
ASTM A370
Test methods and definitions for mechanical testing of steel products
2
ASTM E562
Standard test method for determining volume fraction by systematic manual point count
3
ASTM E112
Standard test method for determining average grain size
4
ISO 3651-2
Determination of resistance to intergranular corrosion of stainless steels
5
ASTM G48
Standard test methods for pitting and crevice corrosion resistance of stainless steels and related
alloys by use of ferric chloride solution
6
ISO 643
Steels – micrographic determination of the apparent grain size
7
ISO 4967
Steel – determination of content of non metallic inclusions – micrographic method using standard
diagrams
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Section 2
SECTION 2 DOCUMENTATION REQUIREMENTS
1 Manufacturing summary
Manufacturer shall submit documentation of the specific manufacturing process and related production
records for products for which approval is requested. Documentation shall include manufacturer’s
metallurgical specifications related the manufacturing process as described in this section.
2 Reheating and forging
The following documentation shall be submitted:
—
—
—
—
—
—
—
—
reheating temperature and time in furnace
forging temperature range (max. temperature and min. temperature)
type and description of forging equipment
sequence of forgings steps and dimensional changes in each step
reduction ratio in each forging step
total reduction ratio at each different cross section
calculation method for reduction ratio calculations
description of intermediate reheating temperatures and hold times.
3 Cleaning and finishing
The following documentation shall be submitted:
— method of surface cleaning
— method of surplus metal removal (de-burring).
4 Heat treatment
The following documentation shall be submitted:
—
—
—
—
—
—
—
—
type of furnace and dimensions
heating source
sketch indicating the positions of thermocouples
working zone dimension and sketch of working zone
accuracy and calibration status of temperature control devices
furnace uniformity test report
furnace loading plan and procedure
heat treatment procedures, specifying temperatures and holding times, and where applicable, information
about heating and cooling rates, quenching medium and cooling medium after tempering
— records of heat treatment
— any re-heat treatment procedure to be given, if applicable
— method of cleaning after heat treatment.
5 Special forging process approval for case hardened gear
transmissions (if applicable)
In order to obtain approval for a forging process for case hardened gear transmissions, as referred in the
rules RU SHIP Pt.4 and DNVGL CG 0036, the following apply:
A detailed description of the forging process shall be given in a manufacturer procedure/specification, shown
to DNV GL, and indicating at least the following parameters:
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reheating temperature and time in furnace
the shaping operations from ingot to finished forging shall be sketched, indicating:
number of blows for each shaping operation
reduction ratio for each shaping operation
typical forging temperature range for each shaping operation
descaling treatment during forging
the minimum and maximum forging ratio for the finished forging shall be given.
Section 2
—
—
—
—
—
—
—
Approval for a “special forging process for case hardened gear transmissions” shall be combined with an MSA
(manufacturing survey arrangement) agreement, referring to the above mentioned manufacturer procedure
describing the approved forging process.
6 Welding (if applicable)
The following documentation shall be submitted:
— description of welding shop:
—
—
—
—
equipment
qualifications of welders and welding supervisors
welding procedure specifications (WPS)
reports on welding procedure qualification tests (WPQR)
— unless otherwise agreed with the Society, the scope of the welding procedure tests shall comply with
RU SHIP Pt.2 Ch.4 Sec.5, and documented as described in the approval of welding workshop (WWA)
programme DNVGL CP 0352.
7 Records, test facilities and procedures
The following documentation shall be submitted:
— visual inspection: relevant templates for recording, and records of previously performed visual inspections
of same or similar products
— details and description of relevant in-house testing facilities and calibration details, test procedures and
qualification of testing personnel
— NDT procedures, equipment for NDT including calibration details, and qualification of personnel for NDT
— information and procedures about important manufacturing and testing routines, such as cutting and
macrographic inspection of products etc.
8 Test results and records
Additional requirements for reporting of test results:
— Sampling:
— sketches, drawings and photos showing the position of test blocks shall be submitted
— Chemical composition:
— a summary of the sampling practices and methods for chemical analysis shall be submitted
— the chemical composition shall be reported in percentage by mass
— the report shall give the specified limits and the measured content of all the required elements.
— Tensile test including test at elevated temperature:
— yield (or proof) stress, tensile strength, elongation and reduction of area shall be included in the
report.
— Charpy V-notch impact toughness test:
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— Metallographic examination:
— high quality photomicrographs showing the microstructure at 100x and 400x/500x magnification shall
be presented with a brief description. The magnification shall be indicated on the micrographs by a
line symbol, e.g. with length of 0.5 mm or 100 µm. Arrows or letters may be used to identify features
referred to in the report
— the ferrite grain size shall be reported, except for stainless steels and steels supplied in quenched and
tempered condition. Ref. ASTM E112
— the applied etching methods for the metallographic examination shall be stated in the report.
— Jominy end quench test (if applicable):
— reporting shall be in the format given in the reference test standard
— the applied test method shall be reported with photographic evidence.
— Corrosion test (if applicable):
— reporting shall be in the format given in the reference test standard.
— Visual examination:
— report for visual inspection, dimensional measurements and surface condition.
— Non-destructive testing:
— detailed records of non-destructive testing with clear conclusions written by qualified personnel shall be
submitted, giving the extent of testing, methods of testing, acceptance criteria, and qualification of the
NDT operator.
— Additionally, for approval for CGF (if applicable):
—
—
—
—
manufacturer shall prepare and submit a specification for the manufacturing process
the results of all test required in Sec.3 [2.12] shall be reported
photos illustrating the material fibres, particularly close to the fillets, shall be presented
the applied etching methods shall be stated in the test report.
— Additionally, for approval of special forging process (if applicable):
— manufacturer shall prepare and submit a specification for the manufacturing process, see [5]
— the results of all test required in Sec.3 [2.12] shall be reported.
— Additionally, for approval of clean steel forgings (if applicable):
— manufacturer shall prepare and submit a specification for the manufacturing process
— the results of all test required in Sec.3 [2.13] shall be reported.
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Section 2
— the heat number, test piece location and orientation, test temperature and absorbed energy (average
and single values).
Section 3
SECTION 3 APPROVAL TESTING
1 Test products and testing scope
1.1 General
The test products shall be selected so that the intended approval scope as outlined in Sec.1 [2] is covered.
The sampling, testing procedures and acceptance criteria shall comply with the relevant requirements of the
DNV GL rules.
1.2 Extent of approval testing
For each selected material grade and delivery condition, testing shall be carried out on forgings from at least
two heats where one heat shall represent maximum thickness/diameter (dimension) and another heat should
represent an average thickness/diameter of the product for which approval is requested.
Where two or more material grades shall be covered by the approval testing, subject to agreement with the
Society, the testing may be reduced to one heat per steel type per application area.
1.3 Selection and position of the test samples
The products shall be representative of the dimensions for which approval is requested. Test material from
which test specimens are extracted, shall be integral with the forgings unless separately forged samples are
permitted by the rules. Samples provided by prolongations or extensions shall have a cross-sectional area
similar to that part of the forging represented. Where separately forged samples are used, these shall have a
cross-section and a reduction ratio similar to that used for the forgings represented.
Test samples and test specimens shall be taken out in the final heat treatment delivery condition and shall
not be subjected to any separate heat treatment.
The position of test pieces within the test sample shall be in accordance with the relevant rule requirements.
Unless specified in the rules sampling positions may be proposed by the manufacturer and then agreed on
case by case basis.
2 Testing requirements
2.1 Chemical composition
The following is required:
— chemical composition shall be determined both by heat and by product analysis and shall comprise all
the elements required by relevant DNV GL rules. The analyses shall also comprise any other elements
intentionally added or designated as residual elements.
2.2 Tensile testing
The following is required:
— two tensile specimens shall be tested from each test block
— yield (or proof) stress, tensile strength, elongation and reduction of area shall be reported
— the mechanical properties shall comply with the relevant DNV GL rules.
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Section 3
2.3 Elevated temperature tensile testing
The following is required:
— for forged steel intended for application at elevated temperatures, tensile test on at least two round
tensile test specimens shall be performed. Test temperature is 300 °C, or as agreed
— yield (or proof) stress, tensile strength, elongation and reduction of area shall be reported
— the tensile test results shall meet the corresponding DNV GL Rule requirements, or of the applicable
specification, for the tested grade.
2.4 Impact testing
The following is required for each heat:
— at least four sets of Charpy V-notch specimens shall be tested
— tests shall be carried out at different temperatures, starting from 20°C below the specified temperature
for that grade, at the specified temperature, and at 20°C above that temperature
— for approval of "grades for low temperature applications" tests shall also be carried out at the lowermost
temperature for which approval is requested (if different from above. Will be specified on approval
certificate)
— the impact toughness requirements shall fulfil the corresponding DNV GL rule requirements at and above
the test temperature specified by the rules
— in case no requirements for Charpy V-notch impact toughness are given and unless otherwise agreed, the
following general requirements applies:
—
—
—
—
—
carbon, carbon-manganese and alloy steels: min. 27 J at +20°C
ferritic and martensitic stainless steels: min. 20 J at –10°C
austenitic stainless steels: min. 27 J at –196°C
duplex stainless steels: min. 27 J at –20°C
longitudinal tests shall be made, except for rings, hollow forgings which are expanded, and disks where
tangential tests shall be made.
2.5 Metallographic examination
The following is required:
— one specimen shall be sampled near the surface and one specimen at the mid-wall thickness of the test
block
— high quality photomicrographs showing the microstructure at 100x and 400x/500x magnification shall
be prepared with a brief description. The magnification shall be indicated on the micrographs by a line
symbol, e.g. with length of 0.5 mm or 100 µm. Arrows or letters may be used to identify features referred
to in the report
— the ferrite grain size shall be reported, except for stainless steels and steels supplied in quenched and
tempered condition. Ref. ASTM E112
— the applied etching methods for the metallographic examination shall be stated in the report.
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Section 3
2.6 The Jominy end quench test (if applicable)
The following is required:
— for case hardening steels (16MnCr5, 20MnCr5, 18CrNiMo7-6 and equivalent), hardenability shall be
determined and reported using Jominy End Quench Test performed according to ASTM A255, or an
equivalent standard.
2.7 Corrosion testing (if applicable)
The following is required:
— test for resistance to corrosion shall be performed for all applicable stainless steel grades. Surface finish
of the test specimens shall be representative of the surface finish of the material/product in final supply
condition
— reporting shall be in the format given in the reference test standard
— duplex stainless:
— corrosion test shall be carried out in accordance with ASTM G48 method A or an equivalent recognised
international standard
— the test sample position shall be at mid thickness of the thickest part of the component subject to
final heat treatment or at a depth of 60 mm for 22Cr duplex and 30 mm for 25Cr duplex, whichever is
less. The test temperature shall be +20°C for type 22Cr duplex and +50°C for type 25Cr duplex. The
exposure time shall be 24 hours
— no pitting on specimen (plate) surfaces is allowed when viewed at 20x magnification. The specimen
2
mass loss shall be less than 4.0 g/m
— austenitic stainless:
— at least two specimens (preferably on material from tensile test specimens) shall be subjected to
intercrystalline corrosion test in accordance with ISO 3651-2 or another recognized international
standard
— the bent specimens shall be free from cracks indicating the presence of intergranular attack.
2.8 Visual examination
The following is required:
—
—
—
—
visual examination shall be conducted according to the relevant rule requirements
the surfaces shall be adequately prepared for inspection
the surfaces shall not be hammered, peened or treated in any way which may obscure discontinuities
examination shall be done for all applicable sides and areas, and manufacturer shall ensure that lifting
devices for handling and turning of the component are available
— when relevant visual examination shall include internal surfaces
— measurements shall be made on all applicable dimensions
— manufacturer shall present representative products used for approval purpose including reports for visual
inspection of the products and surface condition.
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The following is required:
— each product shall be tested in accordance with the requirements of the relevant DNV GL rules
— detailed records of non-destructive testing with clear conclusions, written by qualified personnel shall be
prepared, giving the extent of testing, methods of testing, acceptance criteria, and qualification of the
NDT operator
— inspection shall be done for all applicable sides and areas, and manufacturer shall ensure that lifting
devices for handling and turning of the component are available.
Magnetic particle testing (MT) or liquid penetrant testing (PT):
— MT shall be applied for ferritic steels. PT shall be applied for austenitic and duplex steels.
Ultrasonic testing (UT):
— where required by the rules UT shall be carried out.
2.10 Other tests (if applicable)
Other applicable tests which are carried out by the manufacturer, e.g. to customer purchase specification
requirements should be submitted.
2.11 Approval for CGF (if applicable)
In order to obtain approval for continuous grain flow (CGF) crankshafts or crank throws with improved
utilisation according to DNVGL CG 0037, the following additional test is required:
A complete crank throw of maximum diameter for approval, with the fillets in the finished machined
condition, shall be sectioned/cut along the centerline of the crank throw, in the crank plane. The cross section
surface shall be prepared and etched in order to illustrate the material fibres (flow of segregations). Photos
illustrating the material fibres, particularly close to the fillets, shall be prepared and evaluated. The applied
etching methods shall be stated in the test report.
2.12 Special forging process approval for case hardened gear transmissions
(if applicable)
In order to obtain approval for a forging process for case hardened gear transmissions, as referred in RU
SHIP Pt.4 Ch.4 and DNVGL CG 0036, the following apply:
2.12.1 Test positions
The test positions depend on the position of the gear-teeth within the forgings in question. For this purpose,
an utilisation depth has been defined. Utilisation depth means the maximum machined depth below the
forged surface, for the toothed area of the gear.
For blanks cut from bar, approval will be given for a maximum diameter of bar, and with a specified utilisation
depth below the forged surface.
For separate forgings, approval will be given for a maximum thickness, and with a specified utilisation depth
below the forged surface.
Testing shall be performed at the following positions:
— one sample close to the forged surface
— one sample at maximum utilisation depth.
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Section 3
2.9 Non-destructive testing
— Charpy V-notch impact testing in three directions relative to the defined centerline of the forging:
longitudinal, radial (transversal), and tangential. Unless otherwise agreed, the test temperature shall be
+20°C. The single and average values to be given in the test report
— minimum average value for any test direction shall not be less than 30J, and minimum single value shall
not be less than 21J
— photo macrographs, that is; metallographically prepared and etched samples, magnification 3x to 5x, in
the “plane” defined by the radial and longitudinal directions, illustrating the material segregations shall be
presented. The applied etching methods to be stated in the report
— the structure shall be approved by the Society. The requirements are that the dendrite structure from
solidification of the steel shall be sufficiently deformed, i.e. no visible dendrites
— the prior austenite grain size shall be determined, and photo micrographs, that is; from metallographically
prepared and etched samples, magnification 100x-500x, in the “plane” defined by the radial and
longitudinal directions, illustrating the material austenite grain size shall be presented. The applied etching
methods shall be stated in the report
— the difference in grain size number (ASTM E112 or ISO 643) between the sample at forged surface and
the sample at the maximum depth of utilisation should be less than 2. If the difference is more, the
approval may only be given after special consideration by the Society.
2.13 Clean steel forgings (if applicable)
In order to obtain approval for “Clean Steel Forgings”, either for crankshafts or for gear transmissions, the
following additional requirements apply:
— both chemical composition and material cleanliness (inclusion level) shall be measured at the given
sampling position. The requirements for the chemical composition and cleanliness (inclusion level) is given
by the rules, see RU SHIP Pt.2 Ch.2 Sec.6
— the sampling position for CGF crankshafts is given by ISO 4967 for bar material (from the crank throw)
— the sampling position for gear transmissions, is the maximum utilisation depth (see [2.12.1]).
Note:
The cleanliness (inclusion level) may be measured using other standards than the one referred in the rules, provided the same or
lower inclusion levels are obtained in all respects. In such cases the manufacturer shall prove (by comparison) that the applied
standard gives the same or lower inclusion level.
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Section 3
2.12.2 Testing and test requirements
One typical forged component representative for the maximum diameter or thickness for approval, and
using the representative forging process to be approved, shall be made for the approval testing. Coupon
testing is in general not permitted for the approval of manufacturer for forging process for case hardened
gear transmissions. Before testing, the component shall undergo the complete heat treatment process as
for the typical finished products, including case hardening process (however, blind hardening with the same
temperature/time course will be accepted).
Appendix A
APPENDIX A APPROVAL COVERAGE
1 Approval coverage of material grades and steel types
Ref:
RU SHIP Pt.2
Ch. 2 Sec.6
(unless
otherwise
stated)
Approval coverage
Alloy groups /
material grades
— for all groups: refers to grades indicated in / permitted by the DNV GL rules
C and CMn group
One grade tested will cover entire group, but only the grades with lower specified
yield strength
Alloy steels
Approval of one alloy grade will cover all grades of the same alloy type with same /
lower yield strength and same/lower toughness requirements
C and CMn group
One grade tested will cover entire group, but only the grades with lower specified
specified yield strength
Alloy steels
Approval of one alloy grade will cover all grades of the same alloy type with same/
lower specified yield strength and same/lower toughness requirements
C and CMn group
One grade tested will cover entire group, but only the grades with lower specified
yield strength
Alloy steels
Approval of one alloy grade will cover all grades of the same alloy type with same/
lower specified yield strength and same/lower toughness requirements
Each grade
Each grade shall be approved
C and CMn group
Approval testing of any one grade will also cover all other grades with lower
specified yield strength and lower toughness requirements in the same steel type
group in Sec.6 [6]
Mo and CrMo group
One Mo or CrMo grade tested will cover entire Mo and CrMo group, but only the
grades with lower specified yield strength
C and CMn group
One grade tested will cover entire group, but only the grades with lower specified
yield strength.
Covers in addition C and CMn group as per Sec.8 [2] and Sec.8 [3]
Ni group
One Ni grade tested will cover entire Ni group, but only the grades with higher
design temperature (i.e. C3.5Ni covers C2.25Ni)
CrNi group
Testing of one CrNi grade covers entire CrNi group, except CrNiMo group and grade
GX 5 CrNi 19 9
CrNi grade
GX 5 CrNi 19 9
Covers only grade GX 5 CrNi 19 9
CrNiMo group
Testing of one CrNiMo grade covers entire CrNiMo group
Austenitic-ferritic
(duplex) grades
Approval testing of 25Cr duplex will cover 22Cr duplex grade but not vice-versa
C and CMn group
One grade tested will cover entire group, but only the grades with lower specified
yield strength
Sec.6 [2]
Sec.6 [3]
Sec.6 [4]
Sec.6 [5]
Sec.6 [6]
Sec.6 [7]
Sec.6 [8]
Sec.6 [9]
— for C and CMn grades: always on condition that deoxidation practice and
chemical composition are similar and KV requirements not higher
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(unless
otherwise
stated)
Approval coverage
Alloy groups /
material grades
— for C and CMn grades: always on condition that deoxidation practice and
chemical composition are similar and KV requirements not higher
— for all groups: refers to grades indicated in / permitted by the DNV GL rules
Alloy steels
Approval of one alloy grade will cover all grades of the same alloy type with same/
lower specified yield strength and same/lower toughness requirements
Stainless steel
group
Grouping is same as above for Sec.6 [8]
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Appendix A
Ref:
RU SHIP Pt.2
Ch. 2 Sec.6
Changes – historic
CHANGES – HISTORIC
There are currently no historical changes for this document.
Class programme — DNVGL-CP-0247. Edition May 2016
Page 18
Steel forgings
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