accuracy for as-constructed survey are incorporated. Since padding and backfilling are two activities that impact on the pipeline integrity, the 2005 revision incorporates additional requirements for these activities reflecting outcomes from APIA research on backfilling.
14) Section 11 (Inspection and Testing). This section has been revised to align it with the requirements of AS 2885.5. It specific strength test endpoint requirements for pipelines with a pressure design factor of 0.80, and references APIA research and associated software designed to enable the analysis of the pipe in a proposed (and constructed) test section to be analysed to determine the presence and location of pipe that may be exposed to excessive strain at the intended strength test pressure.
15) Section 12 (Records) Obligations on the developer of a new pipeline to document the design and construction, and to transfer this information to the pipeline operator are clarified and expanded.
16) Appendices Each appendix in the 1997 revision of the standard has been critically reviewed and revised as appropriate. New appendices are provided
reflecting the findings of APIA research, clarification of concepts in the Standard, and providing detailed calculation methods.
In addition to the items identified above, there are a great many changes of lesser significance incorporated in the document to the extent that users should consider it as a familiar, but new Standard.
CONTENTS
Page
SECTION 1 SCOPE AND GENERAL
1.1 SCOPE... 9
1.2 REFERENCE DOCUMENTS ... 9
1.3 DEFINITIONS... 9
1.4 SYMBOLS AND UNITS... 15
1.5 ABBREVIATIONS ... 16
SECTION 2 SAFETY 2.1 BASIS OF SECTION ... 18
2.2 ADMINISTRATIVE REQUIREMENTS... 19
2.3 OVERVIEW OF PROCESS ... 21
2.4 PIPELINE RISK MANAGEMENT ... 24
2.5 STATIONS, PIPELINES FACILITIES AND PIPELINE CONTROL SYSTEMS .... 31
2.6 ENVIRONMENTAL RISK MANAGEMENT ... 31
2.7 ELECTRICAL ... 34
2.8 CONSTRUCTION & COMMISSIONING ... 34
SECTION 3 MATERIALS AND COMPONENTS 3.1 BASIS OF SECTION ... 36
3.2 QUALIFICATION OF MATERIALS AND COMPONENTS... 36
3.3 REQUIREMENTS FOR COMPONENTS TO BE WELDED... 39
3.4 ADDITIONAL MECHANICAL PROPERTY REQUIREMENTS ... 39
3.5 REQUIREMENTS FOR TEMPERATURE AFFECTED ITEMS... 40
3.6 MATERIALS TRACEABILITY AND RECORDS ... 40
3.7 RECORDS... 41
SECTION 4 PIPELINE GENERAL 4.1 BASIS OF SECTION ... 42
4.2 ROUTE... 45
4.3 PIPELINE MARKING ... 46
4.4 CLASSIFICATION OF LOCATIONS ... 48
4.5 SYSTEM DESIGN ... 51
4.6 ISOLATION ... 53
4.7 SPECIAL PROVISIONS FOR HIGH CONSEQUENCE AREAS... 55
4.8 FRACTURE CONTROL ... 57
4.9 LOW TEMPERATURE EXCURSIONS ... 63
4.10 ENERGY DISCHARGE RATE... 64
4.11 RESISTANCE TO PENETRATION ... 64
SECTION 5 PIPELINE DESIGN 5.1 BASIS OF SECTION ... 67
5.2 DESIGN PRESSURE ... 67
5.3 DESIGN TEMPERATURES ... 68
5.4 WALL THICKNESS ... 68
5.5 EXTERNAL INTERFERENCE PROTECTION... 70
5.6 PRE-QUALIFIED PIPELINE SAFETY DESIGN ... 77
5.7 STRESS AND STRAIN... 79
5.8 SPECIAL CONSTRUCTION ... 85
5.9 PIPELINES ASSEMBLIES ... 118
5.10 JOINTING ... 120
5.11 SUPPORTS AND ANCHORS... 121
SECTION 6 STATION DESIGN 6.1 BASIS OF SECTION ... 124
6.2 DESIGN ... 124
SECTION 7 INSTRUMENTATION AND CONTROL DESIGN 7.1 BASIS OF SECTION ... 133
7.2 CONTROL AND MANAGEMENT OF PIPELINE SYSTEM ... 133
7.3 FLUID QUALITY ASSURANCE ... 135
7.4 SCADA... 135
7.5 COMMUNICATION ... 136
7.6 CONTROL FACILITIES... 136
7.7 CRITICAL EQUIPMENT AND REDUNDANCY/BACKUP ... 136
SECTION 8 MITIGATION OF CORROSION 8.1 BASIS OF SECTION ... 137
8.2 PERSONNEL ... 137
8.3 RATE OF DEGRADATION ... 137
8.4 CORROSION MITIGATION ... 138
8.5 CORROSION MONITORING ... 139
8.6 INTERNAL CORROSION MITIGATION METHODS ... 139
8.7 EXTERNAL CORROSION MITIGATION METHODS ... 140
8.8 EXTERNAL ANTI-CORROSION COATING ... 143
8.9 INTERNAL LINING ... 144
SECTION 9 UPGRADE OF MAOP 9.1 BASIS OF SECTION ... 146
10.4 INSPECTION OF PIPE AND COMPONENTS... 151
10.5 CHANGES IN DIRECTION ... 152
10.6 COLD-FIELD BENDS ... 153
10.7 FLANGED JOINTS... 154
10.8 COVERING SLABS, BOX CULVERTS, CASINGS AND TUNNELS... 154
10.9 SYSTEM CONTROLS ... 154
10.10 ATTACHMENT OF ELECTRICAL CONDUCTORS ... 155
10.11 LOCATION... 156
10.12 CLEARING AND GRADING... 156
10.13 TRENCH CONSTRUCTION ... 156
10.14 INSTALLATION OF A PIPE IN A TRENCH ... 157
10.15 PLOUGHING-IN AND DIRECTIONALLY DRILLED PIPELINES... 158
10.16 SUBMERGED CROSSINGS ... 159
10.17 REINSTATEMENT... 159
10.18 CLEANING AND GAUGING PIPELINES ... 159
SECTION 11 INSPECTIONS AND TESTING 11.1 GENERAL... 160
11.2 INSPECTION AND TEST PLAN AND PROCEDURES... 160
11.3 PERSONNEL ... 160
11.4 PRESSURE TESTING ... 160
11.5 COMMENCEMENT OF PATROLLING ... 163
SECTION 12 DOCUMENTATION 12.1 RECORDS ... 164
12.2 RETENTION OF RECORDS ... 165
APPENDICES A REFERENCED DOCUMENTS... 166
B DESIGN CONSIDERATIONS FOR EXTERNAL INTERFERENCE PROTECTION... 171
C INTEGRITY ASSESSMENT OF PIPELINE RISK ASSESSMENTS CONDUCTED IN ACCORDANCE WITH AS 2885 ... 174
D EFFECTIVENESS OF PROCEDURAL MEASURES FOR THE PREVENTION OF EXTERNAL INTERFERENCE DAMAGE TO PIPELINES... 184
E PREFERRED METHOD FOR TENSILE TESTING OF WELDED LINE PIPE DURING MANUFACTURE ... 191
F FRACTURE TOUGHNESS TEST METHODS ... 192
G FRACTURE CONTROL PLAN FOR STEEL PIPELINES ... 194
H STATION PIPING STANDARDS AND DESIGN FACTORS ... 198
I ... J FATIGUE ... 200
K MAOP UPGRADE ... 203
L SUITABILITY OF ASSOCIATED STATION EQUIPMENT... 204
M FACTORS AFFECTING CORROSION... 205
N ENVIRONMENT RELATED CRACKING ... 208
O INFORMATION FOR CATHODIC PROTECTION ... 215
P MITIGATION OF A.C. EFFECTS FROM HIGH VOLTAGE ELECTRICAL POWERLINES ... 217
Q CHANGE IN INTEGRITY (DUE TO DEFECTS IN SERVICE) KNOWN CORROSION DEFECTS PAPER 5.13 ... 225
R PROCEDURE QUALIFICATION FOR COLD FIELD BENDS... 226
S GUIDELINES FOR THE TENSIONING OF BOLTS IN THE FLANGED JOINTS OF PIPING SYSTEMS... 231
T STRATEGIC SPARES PAPER 5.21 ... 245
U RECORD KEEPING PAPER 5.2 ... 246
V STRESS TYPES & DEFINITIONS ... 247
W EXTERNAL LOADS ... 254
X COMBINED EQUIVALENT STRESS... 258
Y PIPE STRESS ANALYSIS... 269
STANDARDS AUSTRALIA Australian Standard
Pipelines—Gas and liquid petroleum Part 1: Design and construction
S E C T I O N 1 S C O P E A N D G E N E R A L 1.1 SCOPE
This Standard specifies requirements for the design and construction of carbon and carbon-manganese steel pipelines falling within the scope of AS2885 Part 0 and associated piping and components that are used to transmit single phase and multiphase hydrocarbon fluids, such as natural and manufactured gas, liquefied petroleum gas, natural gasoline, crude oil, natural gas liquids and liquid petroleum products. AS 2885 Part 0 defines the principles for design, construction, operation and abandonment of petroleum pipelines that form the basis for Design and construction, Welding, Operation and maintenance and Field hydrostatic testing in accordance with AS2885 Parts 1, 2, 3, and 5.
The principles are expressed in practical rules and guidelines for use by competent persons.
The fundamental principles and the practical rules and guidelines set out in AS2885 Parts 1, 2, 3, and 5 are the basis on which an engineering assessment is to be made where these Standards do not provide detailed requirements appropriate to a specific item.
NOTE: AS 2885.4 for offshore pipelines is a standalone document.
Where approved, this Standard may also be used for design and construction of pipelines made with corrosion resistant alloy steels or fibreglass. Where this Standard is used for pipelines fabricated from these materials appropriate requirements shall be established to replace the provisions of this standard in relation to nominated standards for Materials (Section 3), Fracture Control (Section 4.8), Stress and Strain (Section 5.7) and Corrosion (Section 8) and the provisions of AS 2885.2 in relation to Welding and Non Destructive Examination. For fibreglass appropriate requirements shall be established to replace the hydrostatic strength test endpoint provisions of AS2885.5.
This standard is complementary to AS2885.0 but the requirements of this standard take precedence over any corresponding requirements in AS2885.0.
1.2 REFERENCE DOCUMENTS
The documents referred to in this Standard are listed in Appendix A.
1.3 DEFINITIONS
For the purpose of this standard the definitions in AS2885.0 shall apply.
Where this standard imposes requirements, which add to or override the requirements of a permitted Standard or Code, the additional requirements are explicitly stated in this standard and shall be met.
For the purpose of the Standard, the definitions given in AS 1929, AS 2812, AS 2832.1 and those below, apply.
1.3.1 Accessory
A component of a pipeline other than a pipe, valve or fitting, but including a relief device, pressure-containing item, hanger, support and every other item necessary to make the pipeline operable, whether or not such items are specified by the Standard.
1.3.2 Approved and approval
Approved by the Licensee, and includes obtaining the approval of the relevant regulatory authority where this is legally required.
Approval requires a conscious act and is given in writing.
1.3.3 As Low as Reasonably Practicable
Means the cost of further risk reduction measures is grossly disproportionate to the benefit gained from the reduced risk that would result.
NOTE: Guidance on the demonstration of ALARP and grossly disproportionate is given Appendix ALARP
1.3.4 Buckle
An unacceptable irregularity in the surface of a pipe caused by a compressive stress.
1.3.5 Casing
A conduit through which a pipeline passes, to protect the pipeline from excessive external loads or to facilitate the installation or removal of that section of the pipeline.
1.3.6 Collapse
A permanent cross-sectional change to the shape of a pipe (normally caused by instability, resulting from combinations of bending, axial loads and external pressure).
1.3.7 Competent person
A person who has acquired through training, qualification, or experience, or a combination of these, the knowledge and skills enabling the person to perform the task required.
1.3.8 Common threats
Threats which occur at similar locations along the pipeline and which can therefore be treated by a standard design solution for that location type (e.g. road crossings).
1.3.9 Component
Any part of a pipeline other than the pipe.
1.3.10 Construction
Activities required to fabricate, construct and test a pipeline, and to restore the right of way of a pipeline.
1.3.11 Control piping
Ancillary piping used to interconnect control or instrument devices or testing or proving equipment.
1.3.12 Controlled threat
A threat is considered to be controlled when the application of multiple independent protective measures (physical and procedural for external interference and design and/or procedures for other threats) in accordance with this Standard means that for all practical purposes failure as a result of that threat has been removed at that location.
1.3.13 Critical Defect Length
The length of a through wall axial flaw that if exceeded, will grow by plastic failure and result in pipeline rupture. When the defect is smaller than this length, the pipeline will leak.
A critical defect length also exists for part through wall flaws.
1.3.14 Defect
A discontinuity or imperfection of sufficient magnitude to warrant rejection on the basis of the requirements of this Standard.
1.3.15 Dent
A depression in the external surface of the pipe caused by mechanical damage that produces a visible irregularity in the curvature of the pipe wall without reducing the wall thickness (as opposed to a scratch or gouge, which reduces the pipe wall thickness).
1.3.16 Diameter
The outside diameter nominated in the material order.
1.3.17 Failure Analysis
Threats which have not been reduced to accepted risk by external interference protection design or other design measures are then assessed to determine whether or not they will cause failure of the pipeline at the location of the threat. This combination of the characteristics of the threat and the characteristics of the pipeline is called failure analysis.
Failure analysis determines the outcome from the identified threat.
1.3.18 Failure
For the purpose of safety assessment, failure within the Pipeline System has occurred if one or more of the of the following conditions apply:
(a) Any loss of containment (b) Supply is restricted (c) MAOP is reduced
(d) Immediate repair is required
NOTE: It is emphasised that failure is not restricted to loss of containment.
1.3.19 Failure Event
An event that has not been reduced to an accepted risk by external interference protection or design processes, and which involves failure. Failure events are subject to risk evaluation and risk management. Threats that are not reduced to accepted risk become failure events, where their effect on a pipeline results in failure.
1.3.20 Fitting
A component, including the associated flanges, bolts and gaskets used to join pipes, to change the direction or diameter of a pipeline, to provide a branch, or to terminate a pipeline.
1.3.21 Fluid
Any liquid, vapour, gas or mixture of any of these.
1.3.22 Gas
Any hydrocarbon gas or mixture of gases, possibly in combination with liquid petroleum condensates or water.
1.3.23 Heat
Material produced from a single batch of steel processed in the final steel making furnace at the steel plant.
1.3.24 High Consequence Areas
Locations where pipeline failure can be expected to result in multiple fatalities or major environmental damage.
1.3.25 High Consequence Events Failure events in high consequence areas.
1.3.26 High vapour pressure liquid (HVPL)
A liquid or dense phase fluid which releases significant quantities of vapour when its pressure is reduced from pipeline pressure to atmospheric, e.g. LP gas.
1.3.27 Hoop stress
Circumferential stress in a cylindrical pressure containing component arising from internal pressure.
1.3.28 Hot tap
A connection made to an operating pipeline containing hydrocarbon fluid.
1.3.29 Imperfection
A material discontinuity or irregularity that is detectable by inspection in accordance with this Standard.
1.3.30 Inert gas
A non-reactive and non-toxic gas such as argon, helium and nitrogen.
1.3.31 Inspector
A person appointed by the licensee to carry out inspections required by this Standard.
1.3.32 Leak test
A pressure test that determines whether a pipeline is free from leaks.
1.3.33 Location class
An area classified according to its general geographic and demographic characteristics.
1.3.34 Mainline pipework
Those parts of a pipeline between stations, including fabricated assemblies (see AS 2885.1) 1.3.35 Maximum allowable operating pressure (MAOP)
The maximum pressure at which a pipeline or section of a pipeline may be operated.
1.3.36 May
Indicates the existence of an option.
1.3.37 Mechanical interference-fit joint
A joint for pipe, involving a controlled plastic deformation and subsequent or concurrent mating or pipe ends.
1.3.38 Non-credible threat
A threat for which the frequency of occurrence is so low that it does not exist for any practical purpose at that location.
1.3.39 Non-location specific threat
Threats which can occur anywhere along the pipeline (e.g. corrosion).
1.3.40 Pipeline Licensee
The organization responsible for the design, construction, testing, inspection, operation and maintenance of pipelines and facilities within the scope of this Standard.
1.3.41 Petroleum
Any naturally occurring hydrocarbon or mixture of hydrocarbons in a gaseous or liquid state and which may contain hydrogen sulfide, nitrogen, helium and carbon dioxide.
1.3.42 Pig
A device that is propelled inside a pipeline by applied pressure.
1.3.43 Pig trap (scraper trap)
A fabricated component to enable a pig to be inserted into or removed from an operating pipeline.
1.3.44 Piping
An assembly of pipes, valves and fittings connecting auxiliary and ancillary components associated with a pipeline.
1.3.45 Pre-tested
The condition of a pipe or a pressure-containing component that has been subjected to a pressure test in accordance with this Standard before being installed in a pipeline.
1.3.46 Pressure strength
The maximum pressure measured at the point of highest elevation in a test section.
NOTE: Pressure strength for a pipeline or a section of a pipeline is the minimum of the strength test pressures of the test sections comprising the pipeline or the section of the pipeline.
1.3.47 Proprietary item
An item made or marketed by a company having the legal right to manufacture and sell it.
1.3.48 Protection measures–Procedural
Measures for protection on a pipeline which minimize the occurrence of activities by third parties, which could cause failure.
1.3.49 Protection measures–Physical
Measures for protection of a pipeline which prevent external interference from causing failure.
1.3.50 Regulatory authority
An authority with legislative powers relating to petroleum pipelines.
1.3.51 Riser
The connection between a submarine pipeline and a fixed structure, such as processing a platform, jetty or pier.
1.3.52 Risk
The combination of the frequency, or probability, of occurrence and the consequence of a specified failure event (Note: The concept of risk always has two elements: the frequency or probability of which a failure event occurs and the consequences of the failure event).
1.3.53 Rupture
Rupture occurs when a defect size exceeds a critical value, dependent on the applied stress followed by rapid growth until the pipe cylinder has opened to a size equivalent to the diameter of the pipeline. Rupture may initiate propagation of the defect by brittle or tearing fracture until it is arrested.
1.3.54 Shall
Indicates that a statement is mandatory.
1.3.55 Should
Indicates a recommendation.
1.3.56 Sour service
Piping conveying crude oil or natural gas containing hydrogen sulfide together with an aqueous liquid phase in a concentration that may affect materials.
1.3.57 Specified minimum yield stress (SMYS)
The minimum yield stress for a pipe material that is specified in the manufacturing standard with which the pipe or fittings used in the pipeline complies.
1.3.58 Station pipework
Those parts of a pipeline within a station (e.g. pump station, compressor station, metering station) that begin and end where the pipe material specification changes to that for the mainline pipework.
1.3.59 Strength test
A pressure test that confirms that the pipeline has sufficient strength to allow it to be operated at maximum allowable operating pressure.
1.3.60 Telescoped pipeline
A pipeline that is made up of more than one diameter of MAOP, tested as a single unit.
1.3.61 Threat
A threat is any activity or condition that can adversely affect the pipeline if not adequately controlled.
NOTE: Additional information on what constitutes a threat is provided in Appendix ZZZ / HB105
1.3.62 Wall thickness, nominal
The thickness of the wall of a pipe that is nominated for its manufacture, ignoring the manufacturing tolerance provided in the nominated Standard to which the pipe is manufactured. Quantity symbol δN.
1.3.63 Nominated Standard
1.3.64 Loss of integrity
Loss of integrity has occurred if one or more of the following conditions apply:
(a) MAOP is reduced.
(b) Supply is restricted.
(c) Immediate repair is required.
It will generally occur as a result of significant metal damage to the pipeline.
1.3.65 Loss of integrity event
An event that has not been reduced to an accepted risk by external interference protection or design processes, and which involves loss of integrity. Loss of integrity events are subject to risk evaluation and risk management. Threats that are not reduced to accepted risk become loss of integrity events, where their effect on a pipeline results in loss of integrity.
1.3.66 Threat
An activity or condition with the potential to damage the pipeline, cause interruption to service or cause release of fluid from the pipeline.
1.3.67 Risk
Combination of the frequency, or probability, of occurrence and the consequence of a specified loss of integrity event.
NOTE: The concept of risk always has two elements: the frequency or probability of which a loss of integrity event occurs and the consequences of the loss of integrity event.
1.3.68 Pipeline risk assessment
The process comprising Risk Identification, Risk Evaluation and Risk Management set out in Section 2 of this Standard, used to ensure that risks imposed by a pipeline are reduced to ALARP / accepted levels.
1.4 SYMBOLS AND UNITS
NOTE: Unless otherwise noted, pressure and calculations involving pressure are based on gauge pressures
Symbol Description Unit
SH
∆ Stress for longitudinal welds (consistent with API 1102) MPa SL
∆ Stress for girth welds (consistent with API 1102) MPa
σ
Stress MPaσ
E Expansion stress range MPaσflow Flow stress (=SMYS + 68.95 MPa) MPa
σ
H Hoop stress MPaσ
L Longitudinal stress MPaσO Occasional stress MPa
σSUS Sustained stress MPa
σU Ultimate tensile strength MPa
σY Yield strength MPa
µ Poisson’s ratio (stress and strain)
AC Fracture area of the Charpy V Notch specimen mm2
CDL Critical defect length mm
CV Upper shelf CharpyVe Notch energy J
Ca10 Full size specimen (10 x 10 mm) Charpy energy arrest value J c Half of the length of an axial through wall flaw mm D Nominal outside diameter = Pipe diameter = Pipeline diameter mm
Dm Average diameter mm
Dmax Greatest diameter Mm
Dmin Smallest diameter mm
d Branch diameter mm
dW Depth of part through wall flaw mm
E Young’s modulus MPa
FD Design factor for Pressure Containment
FBucket Force exerted at a bucket, correlated against excavator mass kN FMAX Maximum force exerted at bucket (most severe geometry) kN FTP Test Pressure factor
FTPE Equivalent test pressure factor fo Ovality factor
G Sum of allowances mm
L Length of tooth at tip mm
Kc In plane stress intensification factor (fracture initiation toughness) MPa/mm0.5 MT Folias factor
PC Collapse pressure MPa
PD Design pressure MPa
PEXT External pressure MPa
PL Pressure limit MPa
PM Measured pressure from hydrostatic test MPa
PMIN Minimum strength test pressure MPa
Rp Puncture resistance N
RLi Number of runs of np pipe, each run having a length i SDEV Standard deviation of toughness in all heat population
Seff Effective stress (consistent with API 1102) MPa
SF Statistical Factor used to calculate minimum toughness for any heat
SFG Stress limit for girth weld fatigue (consistent with API 1102) MPa SFL Stress limit for longitudinal weld fatigue (consistent with API 1102) MPa
t Wall thickness mm
tDP Wall thickness for internal pressure design mm
tN Nominal wall thickness mm
tW Required wall thickness mm
W Width of tooth at tip mm
WOP Operating weight tonne
1.5 ABBREVIATIONS
Abbreviations Meaning Unit
ALARP As low as reasonably practicable
AS Australian standard
CDL Critical defect length
CHAZOP Control hazard and operability CRA Corrosion resistant alloy
CW Continuously welded
DN Nominal diameter
DWTT Drop weight tear test
EIP External interference protection EIS Environmental impact statement EPRG European Pipeline Research Group
ERW Electric resistance welded
FRP Fibre reinforced plastic
GIS Geographic information system
HAZ Heat affected zone
HAZAN Hazard analysis study HAZOP Hazard and operability study HAZID Hazard identification study HVPL High vapour pressure liquid JSA Job safety analysis
LPG Liquefied petroleum gas
MAOP Maximum allowable operating pressure MPa
MLV Main line valve
MLV Main line valve