Download - 5317_2001_Materials
t c v n v i e t n a m e s e s t a n d a r d
tcvn 5317 : 2001
mobile offshore units -
rules for classification and construction
materials
Hµ néi - 2001
TCVN 5317:2001
Foreword
TCVN 5317:2001 replaces to TCVN 5317:1991.
TCVN 5317:2001 is edited by Vietnam Register and TCVN/TC8 ''Shipbuilding and Offshore'' Technical
Standard Board, is proposed by Ministry of Transportation and Standard - Measure - Quality General
Department, is promulgated by Ministry of Science, Technology and Environmental
2
TCVN 5317:2001
table of content
1. General............................................................................................................................................... 7
1.1. Application...............................................................................................................................................7
1.2. Referance standards...............................................................................................................................7
1.3. Definitions and explanations .................................................................................................................8
1.4. Process of manufacture .........................................................................................................................8
1.5. Chemical composition............................................................................................................................8
1.6. Testing and inspection ...........................................................................................................................8
1.7. Execution of testing and inspection .....................................................................................................9
1.8. Identification of materials.......................................................................................................................9
1.9. Test certificates .......................................................................................................................................9
1.10. Quality and repair of defects ...........................................................................................................10
1.11. Additional test befor rejection.........................................................................................................11
1.12. Marking ..............................................................................................................................................11
2. Rolled steels .................................................................................................................................... 12
2.1. General ...................................................................................................................................................12
2.2. Steel for hull...........................................................................................................................................13
3. Castings........................................................................................................................................... 16
3.1. General ...................................................................................................................................................16
4. Steel forging .................................................................................................................................... 16
4.1. General ...................................................................................................................................................16
3
TCVN 5317:2001
5. Z - steel .............................................................................................................................................16
5.1. General provision ................................................................................................................................. 16
5.2. Chemical composition ......................................................................................................................... 17
5.3. Mechanical properties.......................................................................................................................... 17
5.4. Heat treatment ...................................................................................................................................... 18
5.5. Sampling and scope of testing ........................................................................................................... 18
4
TCVN 5317:2001
Introduction
Mobile Offshore Units - Rules for classification and construction include :
TCVN 5309 : 2001 Classification
TCVN 5310 : 2001 Hull
TCVN 5311 : 2001 Equipment Arrangement
TCVN 5312 : 2001 Stability
TCVN 5313 : 2001 Subdivision
TCVN 5314 : 2001 Fire protection, detection and extincition
TCVN 5315 : 2001 Machinery Installations
TCVN 5316 : 2001 Electrical Installations
TCVN 5317 : 2001 Materials
TCVN 5318 : 2001 Welding
TCVN 5319 : 2001 Safety Equipment
5
TCVN 5317:2001
6
TCVN 5317:2001
1
1
1
2
3
1
1
2
7
Vietnamese TCVN 5317:2001
Mobile Offshore Units - Rules for classification and construction
Materials
. General
.1. Application
This standard is applicable to materials, used to manufacture structures, equipment, as well as
relevant parts of mobile offshore units (abbreviation is unit) defined in TCVN 5309:2001.
Materials and equipment of the unit are to comply with corresponding requirements in TCVN 6259-
7:1997: Welding and requirements in this standard.
Materials having characteristics other than those specified in this Part may be used when the detailed
design data, manufacturing procedure and their use are specially approved by VR. In this case,
detailed data relating to the process of manufacture, chemical composition, mechanical properties,
etc. of the materials are to be submitted to VR for approval .
.2. Reference standards
TCVN 6259-1:1997 to TCVN 6259-11:1997 Rules for classification and construction of steel sea-going
ship .
Mobile Offshore Units - Rules for classification and construction include:
TCVN 5309 : 2001 Classification
TCVN 5310 : 2001 Hull
TCVN 5311 : 2001 Equipment Arrangement
TCVN 5312 : 2001 Stability
TCVN 5313 : 2001 Subdivision
TCVN 5314 : 2001 Fire protection, detection and extincition
TCVN 5315 : 2001 Machinery Installations
TCVN 5316 : 2001 Electrical Installations
TCVN 5317:2001
TCVN 5317 : 2001 Materials
TCVN 5318 : 2001 Welding
TCVN 5319 : 2001 Safety Equipment
1.3. Definitions and explanations
1 The definitions and explanations concerning the general terminology of the rules are given in 1.3
TCVN 5309:2001, and TCVN 6259-1997 .
2 The following definitions and explanations are applied in this standard :
(1) Lamellar tearing means breaking of welded structure elements made of rolled plates or
pipes due to considerable welding stresses and/or external loads applied in the direction
perpendicular to the plate surface, or due to both.
(2) Z-steel means steel with guaranteed through thickness properties which is intended for
welded structures and can withstand considerable stresses perpendicular to the plate
surface .
1.4. Process of manufacture
1 The materials specified in this Part, unless otherwise specially provided or deemed appropriate by VR,
are to be manufactured at the works approved by VR with regard to the process of manufacture of the
materials .
2 The steel material specified in this Part is to be manufactured by basic oxygen convertor, electric
furnace or other processes specially approved by VR .
3 Primary materials such as ingot, slab or billet supplied to other manufacturers or other works in the
same manufacturer are to be manufactured by the process of manufacture of these materials
approved by VR .
1.5. Chemical composition
1 The chemical composition is to be analyzed at an adequately equipped and competently staffed
laboratory on samples generally taken from each melt, and is to comply with the requirements for
chemical composition specified in this rules .
2 A check analysis may be required by VR where deemed necessary .
1.6. Testing and inspection
8
TCVN 5317:2001
1 Materials are to be tested and inspected in the presence of the VR's Surveyor except where
otherwise specially provided, and are to comply with the requirements in this Part .
2 Materials having characteristics other than those prescribed in this part are to be tested and inspected
according to the approved specifications for the testing .
3 VR may dispense with the tests for materials having the appropriate certificates.
4 VR may modify the requirement of presence of testing and inspection by the Surveyor where the
quality of materials and the quality control system of manufacturer are deemed appropriate by VR .
5 VR may request tests under condition of higher or lower temperatures than those specified in this Part
in consideration of the intended service condition of the materials .
1.7. Execution of testing and inspection
1 The manufactures are to afford the surveyor all necessary facilities and access to all relevant parts of
the works to enable him to verify that the approved process is adhered to.
2 The manufactures is to show the order specifications, special requirements, etc. of the materials to the
surveyor prior to the material test.
3 All tests and inspections are to be carried out the place of manufacture prior to delivery, but in the
event of any material proving unsatisfactory in the process of being worked, it is be rejected,
notwithstanding any previous certificate of satisfactory testing and inspection where the surveyor
considers necessary.
4 The testing machines used for the mechanical testing are to be those which have the effective
certificates issued by VR or other organization recognized by VR or other standards deemed
appropriated by VR .
1.8. Identification of materials
1 The manufacturers is to take a suitable measure for identification of ingots, slabs, castings, forgings
and finished pieces, etc. which will enable the material to be traced to the processing details as
mealting, rolling, forging, heat treatments, etc., at all phases of manufacturing process .
1.9. Test certificates
1 The manufacturer is to submit test certificate on the rolled steel materials, which have passed the
specified test requirements for each material mark for the Surveyor's signature. However, another
method may be used instead of Surveyor's signature, provided that it is deemed appropriate by VR .
9
TCVN 5317:2001
2 The test certificate specified in -1 are to contain, in addition to the dimensions, mass, etc., of the steel
material, at least items (1) through (9) of the following particulars :
(1) Purchaser's order number and if known the ship name which the material is intended ;
(2) Identification number or symbol ;
(3) Identification of manufacturer ;
(4) Identification of grade of material ;
(5) Chemical composition (ladle analysis on elements specified in the requirement and added
when necessary) .
(6) Carbon equivalent (Ceq) or cold cracking susceptibility (Pcm) calculated from the following
formula using ladle analysis (only in such a case as specified in this Part) :
(%) 15
CuNi5
VMoCr6
MnCC eq+
+++
++=
5B10V
15Mo
20Cr
60Ni
20Cu
20Mn
30SiCPcm ++++++++= (%)
(7) Mechanical test results;
(8) Condition of heat treatment (e.g. normalized or controlled roll except for as rolled) ;
(9) Deoxidization practice is to be stated (rimed steel only).
The manufacturer is to enter the following statement on the certificate to show that the steel material has
been made by an approved process, and the declaration is to be signed by the personnel of the
manufacturing shop in charge of product quality control or inspection. However, another method may be
used instead of the signature of the person in charge, provided that it is deemed appropriate by VR .
3 The requirements in -1 to -3 are to be applied to the materials which are specified in this Part but
which are other than rolled steel materials.
4 Where primary materials such as ingot, slab or billet are not produced in the works at which it is rolled
or forged, a certificate is to be supplied to the surveyor at the rolling, piping or forging works stating the
process by which it is was manufactured, the name of manufacturer who supplied these, the number
of the cast from which it was made and the ladle analysis. The this case, the manufacturing process of
primary materials such as ingot, slab or billet are deemed appropriate by the surveyor .
1.10. Quality and repair of defects
10
TCVN 5317:2001
1 All materials are to be free from harmful defects. Welding or other means for the purpose of repairing
defects is not permitted unless the extent and method of repair (including welding procedure and heat
treatment) are approved by VR. The repair of defects is to be carried out in the presence of the
surveyor, unless otherwise agreed .
1.11. Additional test befor rejection
1 Where part of the results of any mechanical test except impact test does not conform to the
requirements, but the remainders are satisfactory, additional test specimens twice in number may be
taken from the same material and retests for the failed test may be carried out. In such a case, all of
the test specimens are to conform to the requirements of the Rules.
2 Where the results of impact test do not conform to the requirements, additional tests are to be carried
out in accordance with the requirements in each Chapter .
3 If a heat treated material fails to meet the requirements in any test, retests may be allowed after being
heat treated again. In this case, however, the material is not to be considered as having complied with
the requirements unless all tests fully comply with the test requirements .
4 If the percentage of elongation of any tensile test specimen is less than that specified and any part of
fracture is outside the one-fourth of the gauge length from the center of gauge length, the test is to be
considered as invalid, and an additional test for the material from which the first test specimen has
been taken may be allowed .
1.12. Marking
1 Every materials complying with the requirements is to be clearly stamped with VR brand including the
marks deemed appropriate by VR and material grade mark, and marked with the following particulars
in at least one position by the maker .
(1) Name or mark to identify the maker ;
(2) Number or mark to identify the piece ;
(3) Name, order number or other identification marks (if required by the purchaser ).
2 Materials that are unsuitable for stamping may be marked with brands, seals or by other suitable
means .
3 Materials that cannot be stamped and marked in accordance with the requirements in -1 and -2 due to
small size may be properly marked in the lump .
11
TCVN 5317:2001
2. Rolled steels
2.1. General
1 Rolled steels used in manufactured unit is to comply with requirements in Chapter 3, Part 7A, TCVN
6259-7:1997 and following additional requirements.
2 Types of rolled steel used in manufacture of unit is given table 2.1-1.
3 Steel for special structure is to be approved by TH VR for use according to the purpose and is to be
manufactured under the supervision of the VR by works recognized by that body.
4 Steel for special and primary structures is to be killed and finegrain treated.
5 Steel plates intended for special structures are to undergo the ultrasonic examination. The
examination should be carried out in accordance with standards approved by the VR .
Table 2.1-1 Category of rolled steels for hull
Kind of steels Symbols specified in part 7A
- TCVN 6259-7:1997
Symbols specified in this part
KA KA
KB KB
KD KD
Mild steels
KE KE
KA32, KA36, KA40 KAH
KD32, KD36, KD40 KDH
KE32, KE36, KE40 KEH
High tensile steels
KF32, KF36, KF40 KFH
KA43, KA47, KA51 AQ1
KA56, KA63, KA70 AQ2
KD43, KD47, KD51 DQ1
KD56, KD63, KD70 DQ2
KE43, KE47, KE51 EQ1
KE56, KE63, KE70 EQ2
KF43, KF47, KF51 FQ1
High strength quenched
and tempered rolled
steel
KF56, KF63, KF70 FQ2
12
TCVN 5317:2001
Material coefficients (K) due to kind of those corresponding to tensile strengthare given in Table :
Table 2.1-2 Material coefficient
Kind of steels Symbols of materials Coefficient (K)
Mild steel KA , KB , KD , KE 1,0
KA32, KD32, KE32, KF32 0,78
KA36, KD36, KE36, KF36 0,72
High tensile steels
KA40, KD40, KE40, KF40 *
KA43, KD43, KE43, KF43 *
KA47, KD47, KE47, KF47 *
KA51, KD51, KE51, KF51 *
KA56, KD56, KE56, KF56 *
KA63, KD63, KE63, KF63 *
High strength quenched
and tempered rolled steel
KA70, KD70, KE70, KF70 *
Note: * At the descretion of VR
2.2. Steel for hull
Application of steels for structural members for hull are given in following Fig. where the design service
temperature of materials is lower than -50oC and plate thickness is exceeding to 70mm, however, applied
steels are satisfactory of the VR..
13
TCVN 5317:2001
Fig. 3.2-1 : Application of Mild Steel
*
At the
discrection of
the VR
KEKDKB KA 10
50
40
30
20
0
Thickn. (mm)
(Special)-50 -30 -400 -10 -20
-50-40 (Primary)-30-20 0 -10 o Service temp. ( C) (Secondary)-50-40-30 -20-10 0
Fig 3.2-2 : Application of High Tensile Steel
Thick. (mm) 50
KAH KDH KEH
At the
discrection of
the VR
KFH
40
30
20
10
0
Service Temp. ( C) o 0 -10 -20 -30 (Secondary-40 -50
0 -10 -20 -30 -40 -50 (Primary) 0 -50 -10 20 -30 -40 (Special)
14
TCVN 5317:2001
Fig. 3.2-3 : Application of High Strength Quenched and Tempered Rolled Steel(AQ1,DQ1,EQ1 vµ FQ1)
Thickness (mm)
AQ1
*
DQ1 EQ1 FQ1
At the
discrection
of the VR
50
40
30
20
10
0 Service Temp. ( C) o 0 -10 -20 -30 -40 -50 (Secondary)
0 -10 -20 -50 (Primary)-30 -40 -50 (Special)0 -10 -20 -30 -40
Fig. 3.2-4 : Application of High Strength Quenched and Tempered Rolled Steel(AQ2,DQ2,EQ2 vµ FQ2)
AQ2
Thickness (mm)
*
EQ2DQ2 FQ2
At the
discrection of
the VR
50
40
30
20
10
0
o -10 -20 -30 -40 Service temp. ( C) -50 (Secondary)
0 -10 -20 -30 -40 -50 (Primay)
-10 (Special) 0 -20 -30 -40 -50
15
TCVN 5317:2001
3. Castings
3.1. General
1 Steel castings used for unit has to comply with the requirements in this standard as well as
requirements of Chapter 5, Part 7 - Materials TCVN 6259-7:1997.
2 Steel castings used for making welded structures as well as machinery items and equipment working
at minus degree is to have adequate impact energy. Absorbed energy and temperature are specified
in specification and dependent on minimum specified yield strength for each type of steel, temperature
for each structure is to be approved by VR.
3 Reduction of area in tensile test for steel casting is not to be less than 50%.
4. Steel forging
4.1. General
1 Steel forgings are to conform to the requirements of this standard as well as requirements of Chapter
6, Part 7, Materials, TCVN 6259-7:1997.
2 Steel forging used for special purpose welded structure is to undergo impact testing at a temperature
which is equal to the design temperature for the structure in question, but is not higher than minus
20oC.
3 The guaranteed impact energy value obtained at impact testing is to be stated in the technical
documentation proceeding from the tensile strength of a steel grade and is to be agreed with the VR,
but in no case shall it be less than 30 J when V-notch specimens are tested.
5. Z - steel
5.1. General provision
1 The steel is to be manufactured by the open hearth, electric or basic oxygen process, and is to be
subsequently treated to obtain the required plastic properties of the rolled products in the through
thickness direction. The procedure of treating the steel should be indicated in the type approvall
Certificate and/or Recognition Certificate issued for the works .
16
TCVN 5317:2001
5.2. Chemical composition
1 The basic element and impurities content in carbon and carbon-manganese steel is not to exceed the
values indicated in Table 5.1.
2 As Z-steel, hull structural steel conforming to the Rules may be used provided the requirements of this
Chapter are complied with VR
Table 5.1 Chemical composition of Z-steel (%) (max)
C Mn Si P S
0,18 1,16 0,50 0,03 0,01
3 Z-steel of alternative chemical compositions will be approved by the Register provided that adequate
weldability in conditions under which MODU structure are assembled and resistance to brittle fracture
are guaranteed .
4 If the carbon equivalent (Cdl) in per cent , is to be determined, the following formula should be used:
Mn Cr + Mo + V Ni + Cu Cdl = C + ⎯⎯⎯ + ⎯⎯⎯⎯⎯⎯ + ⎯⎯⎯⎯⎯ (%)
6 5 15
and the value is to be stated in the Certificate
5 Z-steel is to be full killed and treated with grainrefining elements the content of which is determined
when approving the steel .
5.3. Mechanical properties
1 The reduction (Zz) of area after the tensile testing of Z-steel speciments the longitudinal axis of which
is perpendicular to the rolled product surface is not to be less 30%.
Proceding from the minimal service temperature of the structure, the impact test temperature for Z-steel
is to be in accordance with Table 5.2
Table 5.2 Minimal service temperature of structure
Minimal service temperature of structure, (oC) Impact test temperature, (oC)
-10 -20
-20 -40
17
TCVN 5317:2001
-40 -60
2 The required impact energy value for testing V-notch speciments is not to be determined proceeding
from the minimal yield stress for Z-steel according to Table ( Table 5.3).
Table 5.3 The required impact energy value for testing V-notch speciments
Yield stress, (MPa) 235 315 355 390
Impact energy (J) KVL 27 31 34 39
(min ) KVT 18 21 24 26
Where:
KVL : Impact energy for longitudinal specimens
KVT : Impact energy for trensverse specimens
3 The energy is determined on three specimens which are to be cut out transverse to or longtitudinally
along the direction of rolling. Where the impact energy is determined on longitudinal specimens the
required impact energy value for transverse specimens is to be guaranteed by the manufacturer .
4 When Z-steel is tested for the purpose of recognizing the manufacturer the Register may require the
weldability to be checked and the brittle transition temperature to be determined by the method
approved by the Register. The transition temperature is to the in accordance with the service
temperature of the structure .
5 The Register may require the Z-steel resistance to brittle fracture to be confirmed by fracture
mechanics method, dropped weight testing, etc.
5.4. Heat treatment
1 Z-steel is to undergo heat treatment. The heat treatment procedure is to be chosen by the
manufacturer and stated in the Type Approval Certificate and/ or Recognition Certificate, or due to
both .
5.5. Sampling and scope of testing
1 For the purpose of Z-steel testing, fromeach end of a piece sample should be taken of which
specimens for tensile testing, a set of specimens for impact testing and a set of specimens for the
tensile testing in the through-thickness direction are then to be machined .
2 The sequence of machining and the dimensions of specimens as well as the prosedure of tensile and
impact testing are to be in accordance with Chapter 2, Part 7-A TCVN 6259-7:1997 .
18
TCVN 5317:2001
3 The procedure of machining the specimens and the procedure of tensile testing in the through-
thickness direction should be agreed with the Register
4 The percentage reduction of area (Z0) os to be determined as an average value of tensile testing on
three specimens and is not to be lower than the required value .
5 Of each sample the following specimens are to be machined and tested:
(1) One specimen for tensile testing;
(2) One set of three specimens for impact testing;
(3) One set of three specimens for tensile testing in the through-thickness direction
6 For pieces 50 mm or over in thickness, an additional set of three specimens is to be machined to
undergo impact testing, the specimens being cut out with their axes coinciding with the module of the
liece thickness .
7 The Z-steel pieces are to undergo ultrasonic examination procedure as well as kinds and dimensions
of permissible defects are to be agreed with the .
⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯⎯
19