1.
GENERAL
This
specification defines the minimum technical requirements for the supply of
seamless line pipe.
The
following are cited as reference documents to this specification.
•
Basis
of Design 84506-60-20-2L-060
•
General
Specification 84506-60-00-2L-000 - Definitions and Specification
Directory
•
General
Specification 84506-60-00-2L-010 - Quality Assurance / Quality
Control
•
General
Specification 84506-60-00-2L-020 – General Offshore Specification
•
DNV
OS-F101 : Submarine Pipeline Systems 2000
•
API
RP 5L 1 - Recommended Practice for Railroad Transportation of Linepipe
•
API
RP 5L W - Recommended Practice for Marine Transportation of Linepipe
•
API
RP 5L 6 - Recommended Practice for Transportation of Linepipe on
Inland Waterways.
1.2 Pipe furnished to this specification
shall conform to the applicable portions of Section 6 of the latest edition of
the DNV OS-F101 for Submarine Pipeline Systems.
The requirements contained in this specification are inclusive of
Attachment A and the requirements specified in the contract documents including
the minimum design temperature (Tmin). The latest edition of API
Spec 5L shall be used, as a reference for requirements not covered by the DNV
OS-F101 or this specification.
Manufacturer shall be licensed to use the API monogram.
1.3 The following supplementary requirements
in DNV OS-F101 are required:
|
D200
|
Supplementary
Requirement, Fracture Arrest Properties (F)
|
|
D400
|
Supplementary
Requirements for Dimensions (D)
|
|
D500
|
Supplementary
Requirements for High Utilization (U)
|
1.4 COMPANY has the right to require an audit
of the manufacturing facility to determine the current condition of the
facility and to re-certify the facility as being capable of producing pipe to
this specification.
1.5 COMPANY has the right to require
pre-qualification of the manufacturing route proposed for the linepipe.
1.6 CONTRACTOR shall maintain an effective
program for quality assurance and quality control, planned and developed in
conjunction with all functions necessary to meet the requirements of this
specification. The requirement shall be
met by the establishment and implementation of procedures presented to COMPANY.
The program shall demonstrate both recognition of the quality requirements of
the contract and an organized approach to satisfy these requirements. The
program shall ensure that quality requirements are determined prior to
commencement of the work and subsequently satisfied throughout all phases of
production.
1.7 This specification requires the
preparation and submittal of a complete and detailed Manufacturing Procedure
Specification (MPS), which shall be submitted for COMPANY approval after
contract award. MPS shall be approved based on MPQT success. The MPS will be
qualified by performing Manufacturing Procedure Qualification Tests (MPQT) on
joints selected during the first day’s production as detailed in this
specification and Attachment A.
2. MANUFACTURING
2.1 Linepipe shall be quenched and tempered
seamless. The minimum tempering temperature shall be 932°F. COMPANY shall approve manufacturing
procedures and any subsequent modifications during production in writing,
before start or modification of production.
2.2
Linepipe may be non-expanded, cold expanded or cold reduced at
CONTRACTOR option. If pipe is cold expanded or cold reduced and/or end sized by
means of cold deformation, the total maximum fibre strain due to the expansion
or reduction or end sizing shall not exceed one point five percent (1.5%), and
CONTRACTOR shall state minimum and maximum strain values proposed. Cold straightening of pipe joints is not to
induce a permanent strain exceeding 1%.
3. MANUFACTURING MATERIALS
3.2 Chemical composition shall be controlled
within more stringent limits than the maximum values given in table 3.1. CONTRACTOR shall submit the target value and
proposed range of each chemical element to COMPANY for approval. Agreed target values and ranges shall be given
in the approved manufacturing procedures.
3.3 Pipe steel shall conform to the chemical
analysis requirements given in the following table.
table 3-1: CHEMICAL composition
|
Element
|
Ladle
% (1)
|
Check
% (1)
|
|
Carbon(6)
|
0.12
|
0.14
|
|
Manganese
|
1.60
|
1.65
|
|
Silicon
|
0.35
|
0.40
|
|
Sulfur
|
0.008
|
0.008
|
|
Phosphorus
|
0.020
|
0.020
|
|
Copper (5)
|
0.20
|
0.20
|
|
Niobium (2)
|
0.060
|
0.060
|
|
Vanadium (2)
|
0.080
|
0.080
|
|
Titanium (2)
|
0.025
|
0.025
|
|
Aluminum (4)
|
0.060
|
0.060
|
|
Nitrogen (4)
|
0.010
|
0.010
|
|
Chromium (5)
|
0.20
|
0.20
|
|
Nickel (5)
|
0.30
|
0.30
|
|
Molybdenum (7)
|
0.30
|
0.30
|
|
Calcium
|
0.005
|
0.005
|
|
Boron (3)
|
0.0005
|
0.0005
|
Notes:
1.
Maximum
value except where range is indicated.
2. If Nb, V, and Ti are employed in any
combination, the combined total shall not exceed 0.12% as indicated by ladle
analysis.
3. Boron shall not be added intentionally.
4. Minimum Al:N ratio shall be 2:1.
5. The total percentage of chromium,
nickel, and copper shall not exceed 0.60%
6. The minimum carbon based on product
analysis shall be 0.05%.
3.4 The maximum carbon equivalent, calculated by the following
formula, shall not exceed the values specified in DNV OS-F101 for the
appropriate steel grade as indicated by ladle analysis.
C.E. = C + Mn + Cr + Mo + V
+ Ni + Cu
6 5 15
For
carbon less than or equal to 0.12 maximum, the Pcm shall not exceed
the values specified in DNV
OS-F101 for the appropriate steel grade and wall thickness.
Pcm
= C + V + Mo + Cr + Mn + Cu + Si + Ni + 5B
10 15 20 30 60
3.5 Chemical Analysis: Each chemical
analysis taken and reported shall include the percentage of each element
specified or restricted by this specification.
4. NON-DESTRUCTIVE TESTING
4.1 All non-destructive testing (NDT) for
inspection release of pipe shall be carried out after completion of heat treatment
and cold straightening.
4.2 Each pipe joint shall be subject to the
NDT in the following table as a minimum:
table 4-1: TYPE and extent of non-destructive testing1,6
|
Scope
of Testing
|
Method2
|
Extent
of Testing
|
|
Laminar
imperfections at pipe ends covering a circumferential band 50 mm wide
|
UT
|
100%
|
|
Laminar
surface imperfections at end face/bevel
|
MT
|
100%
|
|
Imperfections
in untested ends
|
UT + MT
|
100%
|
|
Residual
magnetism
|
--
|
R3
|
|
Laminar
imperfections in pipe body
|
UT
|
100%
|
|
Thickness
testing
|
UT
|
100%
|
|
Longitudinal
imperfections, pipe body
|
UT
|
100%
|
|
Transverse
imperfections, pipe body
|
UT
|
100%
|
|
Longitudinal
surface imperfections
|
MT5
|
100/10%4
|
|
Transverse
surface imperfections
|
MT
|
100/10%4
|
|
Notes:
1. All testing is to be performed in
accordance with the requirements of Appendix D of the DNV Rules and the
requirements in paragraphs 4.3 through 4.7 below.
2.
UT
= Ultrasonic testing
MT = Surface imperfection testing by Magnetic Particle Techniques
3.
R
= Random testing of approximately 5% of the pipes
4.
100/10%
= 100% testing of the first 20 pipes manufactured, thereafter 10% of the
remaining pipes
5.
EMI
may be substituted for MT provided the untested areas are tested by MT.
|
||
4.3
The UT equipment and method shall be
capable of detecting longitudinal, transverse and laminar defects.
Calibration shall be based on the
requirements of DNV OS-F101 Appendix D and all International Standards as
detailed therein.
Calibration shall be carried out
dynamically at production speed.
During first day production tests, the CONTRACTOR shall
demonstrate the effectiveness of the equipment to detect the inside notches,
outside notches and holes.
4.4 All non-destructive inspection equipment shall be calibrated
and checked as per DNV OS-F101 and Section 4.3
to demonstrate effectiveness, calibration and operational procedure. The
inspection equipment also shall be re calibrated and checked immediately
following any equipment failure, equipment adjustment or start up. These
equipment checks shall be regularly
scheduled in accordance with DNV OS-F101 and sufficient notice given so that company representative may witness
equipment checks each time.
4.5 In all cases where grinding repairs are made as a result of
imperfections disclosed by non-destructive testing, the pipe containing such
repairs shall be given an additional non-destructive test after the grinding
operation. At the option of the CONTRACTOR, the entire length of pipe
may be re-inspected by the method that originally revealed the flaw or the
outside surface of the repaired area shall be re-inspected by magnetic particle
testing and the inside surface by ultrasonic methods.
4.6 All non-destructive inspection procedures described herein
shall be performed at the pipe mill, unless specific approval has been granted
by COMPANY to perform the inspection at the facilities of a third-party
inspection contractor.
4.7 The CONTRACTOR shall demonstrate to the satisfaction of
COMPANY representative the effectiveness of all equipment and procedures during
first-day production qualification.
5. PHYSICAL PROPERTIES AND TESTS
5.1 Testing shall be carried out after heat treatment and cold
straightening. Mechanical properties
required, and the tests to assess them, shall comply with the requirements of
DNV OS-F101 with the additions/changes given in the following sections:
5.2 Testing may be carried out prior to hydrostatic pressure
testing provided it can be demonstrated that there is no significant difference
in mechanical properties in regard to before or after hydrostatic test. This shall be demonstrated on one pipe.
5.3 The mechanical testing is to include the testing shown in
Table 5-1. The tests required for
qualification of the MPS are denoted “Q” and the tests required for production
testing are denoted “P”. Additional
qualification testing is also included in Attachment A.
table 5-1: SEAMLESS linepipe –
mechanical testing1
|
Type
of Test
|
Testing
|
|
Tensile
|
Q&P
|
|
Charpy
V-notch
|
Q&P
|
|
CTOD2
|
see Note 2
|
|
Hardness
|
Q&P
|
|
Charpy
V-notch transition curve
|
Q
|
|
Strain
aging transition curve
|
Q
|
|
Drop
weight tear (if required)
|
Q&P
|
Notes:
1.
All testing is to be performed in accordance with the requirements of
Appendix B
of the DNV OS-F101 as amended by paragraphs 5.3 through 5.4.
of the DNV OS-F101 as amended by paragraphs 5.3 through 5.4.
2. CTOD
tests are not required unless ECA analysis is to be performed for installation
purposes.
5.4 Charpy Impact Tests: Charpy impact
tests shall be performed as per DNV OS-F101 Section 6 and DNV OS-F101 Appendix
B. Specimens shall be tested at least 10° C below the minimum design
temperature. The minimum design temperature shall consider the potential
effects of blow down, gas filling and upset conditions.
6. MILL PRESSURE TEST
6.1 Pipe joints shall be hydrotested in
accordance with the DNV OS-F101 with the following additions:
•
Test
pressure shall be held for a least 10 seconds.
•
Hydrostatic
testing apparatus shall be equipped to provide test pressure and duration
records for every pipe joint length, and shall be available for Company review.
•
Each
hydrostatic test failure or mechanical expansion failure shall be made known to
Company. All failed pipe joints shall be placed aside
and shall be available for Company
inspection.
•
The
hydrostatic test pressure shall be based on the hoop stress as required in
Section 6, E1103 of DNV OS-F101 unless COMPANY permits the use of combined
stresses. The hoop stress as calculated
in Section 6, E1103 shall in no case fall below 90% SMYS.
7. REJECTION OF PIPE JOINTS
7.1 The following requirements shall
supersede those in DNV OS-F101:
•
If
more than ten (10) percent of any day’s production fails to meet the
requirements herein, COMPANY acceptance inspection shall cease and all
continuing production shall be marked and set aside until CONTRACTOR ascertains
and corrects the failure cause.
•
Before
resumption of COMPANY acceptance inspection, CONTRACTOR and COMPANY shall agree
on any additional or increased CONTRACTOR inspection required to assure pipe
joints accepted from the lot produced under upset conditions comply with
minimum requirements herein. CONTRACTOR
inspection shall return to that specified in the manufacturing procedures,
after correction of production difficulties and clearance of all pipe joints on
hold.
7.2 If any test fails because of a machining
or testing error verified by COMPANY, a single replacement test piece shall be
cut from the original test ring, and the initial failure shall be ignored. In all other instances, if any test fails,
then two retest pieces shall be cut from that batch. If either of these fails, the heat will be
rejected.
7.3 If any heat is rejected because of failures in both original
tests and permitted retests, CONTRACTOR may test individual pipe joints from
that heat, and those pipe joints that pass shall be
accepted.
8. CORRECTION OF DEFECTS
8.1 Correction of defects shall comply with the DNV OS-F101.
8.2 Weld repairs are not permitted.
9. DIMENSIONAL TOLERANCES
9.1 Pipe joint lengths shall be between 11.9
and 12.5 meters, with a minimum average of 12.2 meters.
9.2 The bevel angle shall be 30º ± 2.5º.
The root face shall be 1/8-inch (3.2 mm) – 3/16-inch (4.8 mm) or to suit
approved automatic welding process. Bidder may specify an alternate bevel angle
compatible with the proposed welding scheme.
9.3 Dimensions and weights of pipe joints as
well as extent of testing shall comply with DNV OS-F101 section 6 E 1200 and
table 6-15.
10. MARKINGS AND COATING
10.1 Marking and coating shall comply with the
requirements of API 5L and any instructions included in the Purchase
Order. The sequential pipe number shall
be applied to the inside surface of the pipe near one end of the pipe joint,
and other markings may be applied on the inside or outside of the pipe. All markings shall be in English.
10.2 For all pipes, bevels shall
have hard stamp numbers to ensure traceability using a round soft-nosed die.
11. QUALITY CONTROL
CONTRACTOR
shall have as part of its usual business practice an established, routine, and
documented quality control program. This
program shall be used to provide verifiable evidence that materials, design,
fabrication, examination, inspection and testing conform to the SPECIFICATIONS
and requirements established in the Purchase Order. This program shall ensure that all factors
affecting reliability, safety and durability have been evaluated and properly
tested and controlled.
•
CONTRACTOR
shall submit its quality control program for COMPANY review and approval.
•
CONTRACTOR
shall supply materials and pipe joints only from contractors or sub-contractors
that have been approved by COMPANY.
12. INSPECTION AND REJECTION
12.1 CONTRACTOR shall maintain continuous
supervision of its inspection procedures. CONTRACTOR shall allow adequate time
on its schedule for final COMPANY approval of manufacturing and inspection
procedures.
12.2 COMPANY will witness all first-day
production tests. COMPANY shall be
permitted to witness all chemical testing, mechanical testing, equipment
calibration, and steelmaking and to inspect all pipe joints. Sufficient notice (at least 14 days) shall be
given of the time at which the steel production and also pipe production will
start.
12.3 COMPANY shall have free entry at all times
to all parts of the CONTRACTOR’s works that will be concerned with the
manufacture, testing, inspection, quality control and shipping of the pipe
ordered. This includes the steel mill
and the pipe mill. The CONTRACTOR shall
make available to COMPANY, all reasonable facilities to inspect, measure and
test the pipe in all stages of production.
For example, this includes ultrasonic equipment for wall thickness
confirmation.
12.4 COMPANY shall have the option to examine
all materials rejected for any reason.
COMPANY must be informed of any pipe fractures occurring during cold
expansion or hydrostatic testing and of any test specimen failures. All failed materials shall be retained until
examined by COMPANY.
12.5 The CONTRACTOR shall allow COMPANY to
inspect (at a frequency of 10% per quantity) each length of pipe after
manufacture and testing is completed but prior to loading for shipment. COMPANY
shall be provided with, by CONTRACTOR, a means for rotating the pipe and ample
lighting to facilitate thorough visual inspection of both internal and external
surfaces. COMPANY and the CONTRACTOR’s inspectors shall not inspect the pipe
concurrently.
12.6 All pipe joints having repetitive
imperfections must be segregated and COMPANY informed of the extent and cause
of the imperfections. The CONTRACTOR
shall inform COMPANY of actions taken to prevent the imperfections.
12.7 COMPANY shall be given the opportunity to
witness the calibration of each piece of NDT equipment each time that it is
calibrated or re-calibrated.
12.8 After production has commenced on the
Order, CONTRACTOR shall notify COMPANY at least twenty-four (24) hours in
advance of any changes in production schedules.
12.9 COMPANY shall operate
independently of CONTRACTOR inspectors.
13. SHIPMENT
13.1 CONTRACTOR shall submit to Company for approval, procedures for
handling, stacking during storage, and stacking and securing pipe for
shipment.
13.2 All handling, loading and unloading shall
be performed in such a manner as to avoid mechanical damage and corrosion,
using slings or pipe-shaped padded hooks with a spreader bar attached.
13.3 Rail cars, trucks, lighters, ships or other
conveyances shall be cleaned of debris or any substance that might damage the
pipe prior to loading.
13.4 Suitable timber and other dunnage shall be
used to protect the pipe against damage in transit.
13.5 Loading onto or into rail cars, trucks,
lighters, ships or other conveyances shall be performed in accordance with
Project Specification 84506-60-30-2L-270 and API 5L1 or API 5LW as appropriate.
13.6 No on-deck overseas shipment is allowed
without prior written approval by Company.
13.7 Finished pipe shall be stored at the mill
or marshalling yard in a manner to prevent damage and excessive corrosion of
the pipe.
13.8 Pipe shall not rest on projections that
could result in point stress or be allowed to rub on an adjacent object.
13.9 Bevel protectors shall be provided for all
pipe ends.
14. RECORDS
All
records indicated herein shall be fully identified with the specific materials
they represent. Records shall be
available for COMPANY examination at the time and place of inspection, whether
at the point of manufacture or other CONTRACTOR locations. CONTRACTOR shall
keep these records for three years after pipe joints have been shipped:
•
Certificates
of Compliance of required nondestructive testing.
•
All
NDE reports records and charts for review by COMPANY or third party inspectors.
•
Pyrometer
charts or other detailed records for all heat treatment performed, such as
postweld, normalizing, and heating for forming.
•
Charts
or other records of required hydrostatic, pneumatic and other tests. Test logs shall include test data, testing
fluid, test duration, test fluid temperature, test pressure, a description of
the item tested, a traceable identifying number such as a shop order number,
and the signature of CONTRACTOR shop inspector witnessing the test.
15. DOCUMENT SUBMITTALS
All
documentation shall be compiled into a data book. CONTRACTOR shall submit to
COMPANY for approval, all documentation produced during the WORK as required by
the DNV OS-F101, including but not limited to the following:
|
a.)
Q.C. Procedures
|
|
b.)
Ladle Analysis (each heat)
|
|
c.)
Product Check Analysis (each heat)
|
|
d.)
Results of Manufacturing Procedure Qualification
|
|
e.)
Certified Examination Reports
|
|
f.)
Certified Mechanical Test Reports
|
|
g.)
Mill Certificates
|
|
h.)
Special Tests Results required by this Specification
|
|
i.)
Storage Procedures
|
|
j.)
Release Certificates
|
All
certificates shall be in the English language, use metric units of measure and
shall be visibly signed by both CONTRACTOR and COMPANY.
All
data shall be provided in hard copy and in electronic format.
Attachment A
MANUFACTURING PROCEDURE QUALIFICATION
A.1 GENERAL
Pipe
joint production procedures shall be qualified by actual testing. CONTRACTOR
shall submit written procedure, for COMPANY review and approval, with bid.
A.2 WRITTEN PROCEDURE SPECIFICATION
CONTRACTOR
written procedures shall contain the following minimum information:
A.2.1 Steel maker and steel making processes,
including selection and percent of scrap and details of hot metal treatment
secondary refining techniques, ladle treatments, degassing, casting techniques
and equipment used for continuous casting, if applicable.
Amount
of slab or round removed from front and end of pour, method of taking ladle
analysis, procedures for sulfur prints or macros of slab, scarfing practice.
A.2.2 Chemical Composition and Target Chemistry
A.2.3 Details of pipe making and sizing.
A.2.4 Details of heat treatment including:
•
Austenizing
temperature with tolerances
•
Maximum
and minimum time at austenizing temperature
•
Details
of quenching including water flow and water temperature control
•
Tempering
temperature with tolerances
•
Maximum
and minimum time at tempering temperature
•
Methods
used to minimize distortion
A.2.5 Details of cold straightening and cold
sizing including maximum cold strain.
A.2.6 CONTRACTOR shall supply data on pipe joints
with a similar chemistry and manufacturing process, which shows adequate field
weldability to COMPANY. Without such
data, or as directed by COMPANY, CONTRACTOR shall conduct field weldability
trials with COMPANY approved manual (stick) and semi-automatic / automatic
(GMAW) welding procedures.
A.2.7 Pipe joint hydrotest and NDT procedures.
A.2.8 Essential variables for each manufacturing
step are to be established. The
following changes in the manufacturing processes for linepipe will require re-qualification
of the MPS.
•
Any
change in raw material scrap content, when relevant, above that qualified.
•
Any
changes in steelmaking process, alloying practice, rolling or working condition
and heat treatment.
•
Increase
in ladle analysis of 0.02%C or 0.03 in Pcm values above that qualified.
•
Any
change in pipe forming process.
•
Any
change in final heat treatment condition.
•
Any
change in method for cold expansion/reduction and any increase in cold
expansion/sizing/finishing from that used during qualification.
A.3 Manufacturing Procedure Qualification Test
On
the first day of production, COMPANY shall randomly select three (3) pipe
joints for examination and testing in accordance with the requirements of the
DNV-OS-F101 and the following:
A.3.1 Each test pipe joint shall be examined
visually on both surfaces for compliance with the quality requirements of this
specification.
A.3.2 All of the inspection, measurement, testing
and NDT requirements for production pipe contained in the main body of the
specifications shall be performed on each test pipe joint.
A.3.3 CTOD Testing
CTOD
testing shall be conducted in accordance with BS 7448 and Appendix B of the DNV
Rules. CTOD testing shall be performed
on the base metal from each of the test pipe joints. All values shall be greater than 0.15
mm. Values obtained shall be submitted
to Company.
A3.4 Strain Aging Test
Strain
aging testing shall be performed in accordance with DNV OS-F101 Appendix B and
Section 6, D200.
A3.5 Charpy
V-notch transition curve
Charpy
V-notch energy and shear area curves are to be established in accordance with
DNV OS-F101 Appendix B and Section 6, D200.
A3.6 Weldability
Test
Four,
full-length pipe joints shall be selected from the first day’s production for
weldability testing to be conducted by the installation contractor. These joints shall receive all of the
inspections and testing and acceptance required of production pipe joints. The joints shall be shipped as directed in
the Purchase Order.
A.3.7 For procedure approval, the results of all
the above tests shall comply with the minimum requirements of this
specification.