AS 1210 Supp2—1999

AS 1210 Supplement 2—1999

Pressure vessels—Cold-stretchedaustenitic stainless steel vessels

(Supplement to AS 1210—1997)

This Australian Standard was prepared by Committee ME/1, Pressure Equipment. Itwas approved on behalf of the Council of Standards Australia on 30 June 1999 andpublished on 5 September 1999.

The following interests are represented on Committee ME/1:

A.C.T. WorkCover

Australasian Corrosion Association

Australasian Institute of Engineer Surveyor

Australian Aluminium Council

Australian Building Codes Board

Australian Chamber of Commerce and Industry

Australian Industry Group

Australian Institute of Energy

Australian Institute of Petroleum

Australian Liquefied Petroleum Gas Association

Boiler and Pressure Vessel Manufacturers Association of Australia

Bureau of Steel Manufacturers of Australia

Department for Administration and Information Services, S.A.

Department of Employment Training and Industrial Relations, Qld

Department of Industries and Business, N.T.

Department of Infrastructure, Energy and Resources, Tas.

Department of Labour, New Zealand

Electricity Corporation of New Zealand

Electricity Supply Association of Australia

Institute of Materials Engineering Australasia

Institution of Engineers, Australia

Institution of Professional Engineers, New Zealand

National Association of Testing Authorities, Australia

New Zealand Engineering Federation

New Zealand Heavy Engineering Research Association

New Zealand Institute of Welding

New Zealand Petrochemical Users Group

Victorian WorkCover Authority

Welding Technology Institute of Australia

WorkCover N.S.W.

WorkSafe Western Australia

Review of Australian Standards.To keep abreast of progress in industry, Australian Standards are subjectto periodic review and are kept up to date by the issue of amendments or new editions as necessary. It isimportant therefore that Standards users ensure that they are in possession of the latest edition, and anyamendments thereto.Full details of all Australian Standards and related publications will be found in the Standards AustraliaCatalogue of Publications; this information is supplemented each month by the magazine ‘The AustralianStandard’, which subscribing members receive, and which gives details of new publications, new editionsand amendments, and of withdrawn Standards.Suggestions for improvements to Australian Standards, addressed to the head office of Standards Australia,are welcomed. Notification of any inaccuracy or ambiguity found in an Australian Standard should be madewithout delay in order that the matter may be investigated and appropriate action taken.

This Standard was issued in draft form for comment as DR 98308.

AS 1210 Supp2—1999

AS 1210 Supplement 2—1999

Pressure vessels—Cold-stretchedaustenitic stainless steel vessels

(Supplement to AS 1210—1997)

Originated as part of SAA Rul PE/1.Revised and redesignated in part as AS 1210 Supplement 2—1999.

Published by Standards Australia(Standards Association of Australia)1 The Crescent, Homebush, NSW 2140

ISBN 0 7337 2824 3

AS 1210 Supp2 — 1999 2

PREFACE

This Supplement was prepared by the Joint Standards Australia/Standards New ZealandCommittee ME/1, Pressure Equipment to supersede SAA Rul PE/1*,Rulings to thepressure equipment Standards—Enquiry 101/95and incorporate requirements for cold-stretched austenitic stainless steel vessels into AS 1210—1997,Pressure vesselsas a newSupplement 2.

In this Supplement, significant changes are made to the above Ruling to take account ofrecent research, developments and extensive successful experience, and to clarify anumber of areas where interpretation difficulties have arisen. These changes are asfollows:

(a) Adoption of design factor for tensile strength equal to 2.5.

(b) Elimination of minimum amount of cold stretch.

(c) Revision of requirements on thickness variations.

(d) Provision for the use of rings and doubling pads.

(e) Provision to utilize increased strength at low temperature.

(f) Increased range of temperature application.

(g) Clarification of opening reinforcement.

(h) Introduction of conditions for use in transportable vessels.

(i) Alternative fatigue requirements.

(j) Inclusion of selected requirements from Pressure Equipment Note PEN—E15, Cold-stretched Vessels(now withdrawn) which aimed to clarify a number of matters inthe interim.

The Supplement uses AS 1210 and its Supplement 1 as its general basis of design andmanufacture and provides additional or modified requirements and conditions for pressurevessels cold-stretched to enhance proof strength.

Reference should be made to general background information in the prefaces of AS 1210and Supplement 1.

A supporting technical note is to be prepared to provide answers to a number of queriesrelating to cold-stretched vessels, to record the background and basis of this Supplement,and to provide some useful references and examples.

Acknowledgment is gratefully made for the assistance provided by theSwedish Cold-stretching Directive 1991produced by the Swedish Pressure Vessel Commission.

The sections and clauses in this Supplement (Supplement 2) are prefixed with‘2S’ asdistinct from clauses in AS 1210 Supplement 1—1990, Unfired pressure vessels—Advanced design and construction, which are prefixed with‘S’.

* SAA Rul PE/1 is published as a subscription service whereby enquiries from subscribers about theapplication of pressure equipment Standards are answered. For further information, contact any StandardsAustralia Office.

3 AS 1210 Supp2 — 1999

CONTENTS

Page

SECTION 2S1 SCOPE AND GENERAL REQUIREMENTS2S1.1 SCOPE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52S1.3 APPLICATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52S1.6 CLASSES OF VESSEL CONSTRUCTION. . . . . . . . . . . . . . . . . . . . . . 52S1.7 APPLICATION OF VESSEL CLASSES AND TYPES. . . . . . . . . . . . . . 52S1.8 DEFINITIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62S1.12 DESIGNATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

SECTION 2S2 MATERIALS2S2.1 MATERIAL SPECIFICATIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72S2.3 ALTERNATIVE MATERIAL AND COMPONENT SPECIFICATIONS . . 72S2.7 MATERIAL FOR HIGH TEMPERATURE SERVICE. . . . . . . . . . . . . . . 7

SECTION 2S3 DESIGN2S3.2 DESIGN CONDITIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82S3.3 DESIGN STRENGTHS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82S3.5 WELDED AND BRAZED JOINTS. . . . . . . . . . . . . . . . . . . . . . . . . . . . 92S3.7 CYLINDRICAL AND SPHERICAL SHELLS SUBJECT TO INTERNAL

PRESSURE AND COMBINED LOADINGS . . . . . . . . . . . . . . . . . . . . 102S3.8 THICK-WALLED CYLINDRICAL AND SPHERICAL VESSELS SUBJECT

TO INTERNAL PRESSURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102S3.9 CYLINDRICAL AND SPHERICAL SHELLS SUBJECT TO EXTERNAL

PRESSURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102S3.12 DISHED ENDS SUBJECT TO INTERNAL PRESSURE. . . . . . . . . . . . . 102S3.18 OPENINGS AND REINFORCEMENTS. . . . . . . . . . . . . . . . . . . . . . . . 102S3.19 CONNECTIONS AND BRANCHES. . . . . . . . . . . . . . . . . . . . . . . . . . . 112S3.23 JACKETED VESSELS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112S3.24 VESSEL SUPPORTS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112S3.25 ATTACHED STRUCTURES AND EQUIPMENT. . . . . . . . . . . . . . . . . 112S3.26 TRANSPORTABLE VESSELS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112S3.33 VESSELS WITH INCREASED DESIGN STRENGTH

AT LOW TEMPERATURE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

SECTION 2S4 MANUFACTURE2S4.2 WELDED CONSTRUCTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 142S4.5 BRAZED CONSTRUCTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

SECTION 2S5 TESTING AND QUALIFICATION2S5.3 NON-DESTRUCTIVE EXAMINATION . . . . . . . . . . . . . . . . . . . . . . . . 152S5.10 HYDROSTATIC TESTS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152S5.11 PNEUMATIC TESTS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 162S5.17 SPECIAL EXAMINATIONS AND TESTS . . . . . . . . . . . . . . . . . . . . . . 16

SECTION 2S6 ASSURANCE OF PRODUCT QUALITY. . . . . . . . . . . . . . . . . . . . 17

AS 1210 Supp2 — 1999 4

PageSECTION 2S7 MARKING

2S7.1 MARKING REQUIRED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 172S7.7 REPORTS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

SECTION 2S8 PROTECTIVE DEVICES AND OTHER FITTINGS. . . . . . . . . . . . . 17

SECTION 2S9 PROVISIONS FOR DESPATCH. . . . . . . . . . . . . . . . . . . . . . . . . . 17

SECTION 2S10 NON-METALLIC VESSELS. . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

APPENDIX 2SR LIST OF REFERENCED DOCUMENTS. . . . . . . . . . . . . . . . . . 18

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5 AS 1210 Supp2 — 1999

STANDARDS AUSTRALIA

Australian Standard

Pressure vessels—Cold-stretched austenitic stainless steel vessels

(Supplement to AS 1210—1997)

S E C T I O N 2 S 1 S C O P E A N D G E N E R A LR E Q U I R E M E N T S

Section 1 of AS 1210 shall apply, with the following additions to particular Clauses.

2S1.1 SCOPE Clause 1.1 of AS 1210 applies with the following additions:

Supplement 2 (hereafter referred to as‘the Supplement’ or ‘this Supplement’) specifiesrequirements for two additional classes of vessel identified as Class 1S and Class 2SA.This Supplement specifies requirements for pressure vessels designed and fabricated fromaustenitic stainless steel, cold-stretched to enhance proof strength; and hence permitshigher design strengths than those specified in AS 1210 and Supplement 1.

Only those requirements which supplement or differ from those specified in AS 1210 arespecified in this Supplement.

2S1.3 APPLICATION Clause 1.3 of AS 1210 applies with the following additions:

Cold-stretched vessels shall be limited to static and transportable, insulated and non-insulated vessels—

(a) made of austenitic stainless steel cold-stretched after welding is completed (exceptfor small minor welds);

(b) with a maximum nominal wall thickness not exceeding 30 mm;

(c) with design temperature not exceeding 400°C;

(d) used only with substances known to have no deleterious effect on the stainless steelof the vessel under the intended service conditions; and

(e) which are not of riveted or brazed construction.

Vessels which contain lethal substances shall be of Class 1S construction.

2S1.6 CLASSES OF VESSEL CONSTRUCTION Clause 1.6 of AS 1210 applieswith the following additions:

This Supplement specifies requirements for the following two additional classes of vessel:

(a) Class 1S Cold-stretched, with welded joint efficiency as for Class 1 of AS 1210,and non-destructive examination and fatigue requirements as forClass 1H vessels of AS 1210 Supplement 1.

(b) Class 2SA As for Class 1S but with non-destructive examination and fatiguerequirements as for Class 2HA of AS 1210 Supplement 1.

2S1.7 APPLICATION OF VESSEL CLASSES AND TYPES Clause 1.7 of AS 1210applies with the following additions to particular Clauses:

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AS 1210 Supp2 — 1999 6

2S1.7.2.4 Mixed classes of welded construction

A vessel may consist of cold-stretched section(s) constructed to Class 1S or 2SA joined tosections or parts constructed to other classes covered by AS 1210 and Supplement 1,provided each part complies with the respective class or classes, and Clause 1.7.2.4 iscomplied with.

2S1.8 DEFINITIONS Clause 1.8 of AS 1210 applies with the following additions:

2S1.8.32 Cold-stretched pressure vessel—a pressure vessel subjected to a calculatedand controlled internal pressure at ambient temperature (cold-stretching pressure) aftercompletion. This pressure stretches the steel, as necessary, and within limits to raise itsproof strength and to ensure that the actual thickness × proof strength satisfies the design.

NOTE: Vessels made of cold-stretched or work hardened plate will normally have very littleplastic deformation during cold-stretching.

2S1.8.33 Cold-stretched plate—plate, sheet or strip cold-stretched in a cold-stretchingmachine, after solution heat treatment, to a controlled 0.2% residual proof strength e.g.350–450 MPa (or 400–500 MPa for nitrogen-alloyed steels).

2S1.12 DESIGNATION Clause 1.12 of AS 1210 applies with the following additions:

Cold-stretched vessels shall be designated as:

For Class 1S welded construction. . . . . . . . . . . . . . . . . . . . . . . . . . . . AS1210—1S.

For Class 2SA welded construction. . . . . . . . . . . . . . . . . . . . . . . . AS1210—2SA.

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7 AS 1210 Supp2 — 1999

S E C T I O N 2 S 2 M A T E R I A L S

Section 2 of AS 1210 shall apply, with the following additions to the particular Clauses.

2S2.1 MATERIAL SPECIFICATIONS Clause 2.1 of AS 1210 applies with thefollowing additions to particular Clauses.

2S2.1.1 General The material used for pressure parts or parts attached to pressureparts of cold-stretched vessels shall be restricted to one of the types of austenitic stainlesssteels listed in AS 1210 or an equivalent Standard, e.g. ISO 9328-5.

The steel shall be in the annealed (solution heat-treated) condition with an elongation ofnot less than 35% on a gauge length of 50 mm or equivalent except for cold-stretched orwork hardened plate as specified in this Clause (2S2.1.1).

Only grades which are proven to be metallurgically stable at the intended servicetemperatures are permitted e.g. ASTM A240 Types 304, 304L, 304LN, 316, 316L,316LN, 317L, 321, 347 for use between −196°C and +400°C. For other types or lowertemperature, suitable type tests shall establish that the properties of parent metal, heataffected zone and weld metal are in accordance with this Supplement after 1000 hours atmaximum and minimum design temperatures.

Cold-stretched plate or work hardened (cold rolled) steel may be used provided that thefollowing requirements are satisfied:

(a) The ratio actual 0.2 percent proof strengthactual tensile strength

shall not exceed 0.80 .

(b) The maximum hardness shall not exceed that permitted by the original materialspecification.

(c) The elongation of the steel as supplied shall be not less than 30 percent on a gaugelength of 50 mm or equivalent.

(d) The steel shall be shown, by suitable testing, to have a lateral expansion of at least0.38 mm at the minimum operating temperature in the final operating condition.Suitable testing by the vessel manufacturer or steel maker shall be at least one set ofCharpy tests on the steel type in both the maximum and minimum work hardenedconditions, both welded and non-welded.

(e) The vessel manufacturer or steel maker shall document that the steel is suitable forthe design and service conditions.

2S2.3 ALTERNATIVE MATERIAL AND COMPONENT SPECIFICATIONSClause 2.3 of AS 1210 applies with the following addition.

2S2.3.3 Clause 2.3.3 of AS 1210 does not apply except when permitted by Clause 2.3.4.

2S2.7 MATERIAL FOR HIGH TEMPERATURE SERVICE Clause 2.7 of AS 1210applies with the following addition.

2S2.7.1 General The maximum service temperature for cold-stretched vessels shall be400°C.

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AS 1210 Supp2 — 1999 8

S E C T I O N 2 S 3 D E S I G N

Section 3 of AS 1210 with the exception of Clauses 3.8, 3.13 to 3.17 and 3.27 to 3.32shall apply, with the following additions and modifications to particular Clauses.

2S3.2 DESIGN CONDITIONS Clause 3.2 of AS 1210 applies with the followingadditions.

S3.2.8 Design for cold-stretching This Clause provides additional design requirementsfor cold-stretched vessels. Specific reference should also be made to Clause 3.2.5 (low-temperature service) of AS 1210.

Particular care shall be taken to ensure that all openings and attachments (e.g. nozzles,pads and supports) are designed, located and fabricated so as to avoid discontinuities andsudden changes in stiffness or rigidity and to limit localized strain to 10% particularly inthe circumferential direction. Calculations for the vessel support system shall be subjectedto design verification. The calculations shall take account of all combinations of stressesdue to restraint, discontinuities, thermal effects and vessel loadings including those undernormal operating conditions and cold stretching.

It is recommended that, where practical, attachment welds be arranged axially wherepossible to allow free stretching.

In addition to the design requirements specified in this Supplement, it shall be shown bycalculation or test that the permanent strain from cold stretching will not exceed 10% inareas of local strain concentration, except this is not required for dished ends complyingwith this Supplement.

NOTE: The amount of local strain may be determined in accordance with AS 1210Supplement 1, BS 5500 or equivalent.

The vessel shall meet the fatigue requirements of Clause S3.1.5 of AS 1210 Supplement 1or BS 5500 or equivalent.

The vessel shall be constructed to Class 1 requirements of AS 1210 except where thisSupplement specifies other requirements.

2S3.3 DESIGN STRENGTHS Clause 3.3 of AS 1210 applies with the followingmodification.

2S3.3.1.1 General

For cold-stretched pressure vessels the maximum allowable design tensile strength (f)shall be:

(a) For design temperatures up to and including 20°C, f is the lower of:

Re/1.5 (Note 1); and

. . . 2S3.3.1(1)Rm (Note 2)

2.5 (Note 3)

(b) For temperatures over 20°C and up to and including 400°C, the value from Item (a)shall be reduced by the amount in Table 2S3.3.1.

(c) For temperatures below 0°C, the provisions of Clause 3.33 of AS 1210 may also beapplied.

NOTES:

1 Re = specified minimum yield or proof stress (0.2% offset) at 20°C in the solution heat-treated condition, or in the specified supply condition, or it may be taken as the stressactually developed at the cold-stretch pressure.

2 Rm = specified minimum tensile strength at 20°C in the solution heat-treated condition or inthe specified supply condition. Alternatively, this may be increased for each plate, by 50%

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9 AS 1210 Supp2 — 1999

of the difference in strength betweenRm and the value of the actual tensile strength of theplate used in the vessel, as recorded on the steel maker’ s material test certificate. In thiscase the actual tensile strength is also limited to 125% ofRm. Also suitable tests arerequired to assess the actual strength of formed ends or other parts where fabricationmethods may reduce tensile strength.

3 The factor 2.5 may be changed to 2.25 under the following conditions:

(a) f does not exceed 258 MPa.

(b) Hydrostatic test pressure is not less than 1.5× calculation pressure for all parts of theshell and ends.

(c) Design temperature does not exceed 20°C and the design minimum temperature is below−50°C.

(d) At least two pressure relief devices are fitted, one set at the design pressure (withinallowable tolerance) and the other not greater than 1.21 times the design pressure.

(e) If the vessel is transportable, it also has external mechanical and thermal protection asspecified in Clause 2S3.26.

TABLE 2S3.3.1

DESIGN TENSILE STRENGTH REDUCTION VALUES

Steel type(ASTM A240)

Design tensile strength, reduction values, MPa

Design temperature °C

20 50 75 100 125 150 175 200 225 250 275 300 325 350 375 400

Standard types

304, 304L, 316.316L

0 40 55 70 80 90 100 110 115 120 125 130 135 140 145 150

Ti or Nb - Alloyedtypes

321, 3470 30 40 50 58 65 72 80 82 85 88 90 92 95 98 100

N - Alloyed types

304LN, 316LN 0 60 80 100 112 125 138 150 158 165 172 180 188 195 202 210

2S3.5 WELDED AND BRAZED JOINTS Clause 3.5 of AS 1210 applies with thefollowing additions and modifications.

2S3.5.1.3 Location of joints Special reference should be made to Clause 3.5.1.3 ofAS 1210.

2S3.5.1.4.6 Welded joints with backing stripsJoggled joints shall not be used.

Circumferential joints with retained backing strips may be used.

2S3.5.1.8 Butt-weld between plates of unequal thicknessThe thickness of plates inadjacent shell strakes and in ends of cold-stretched vessels may be varied provided—

(a) all plates in any one strake or in an end are the same nominal thickness;

(b) the difference in thickness between plates in adjacent shell strakes do not exceed20 percent of the thickness of the thinner plate; and

(c) weld details between plates of different thickness comply with Clause S3.5.1.8 ofAS 1210 Supplement 1.

NOTE: The thickness of ends and adjacent shell strakes is not limited by Item (b).

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AS 1210 Supp2 — 1999 10

2S3.5.3 Brazed joints Brazed joints shall not be used in cold-stretched vessels exceptfor attached piping.

2S3.5.4 Soldered joints Soldered joints shall not be used in cold-stretched vesselsexcept for attached piping.

2S3.7 CYLINDRICAL AND SPHERICAL SHELLS SUBJECT TO INTERNALPRESSURE AND COMBINED LOADINGS Clause 3.7 of AS 1210 applies with thefollowing additions.

2S3.7.5 Vertical cylindrical vessels under combined loading For cold-stretchedvessels, suitable provision shall be made to avoid axial buckling due to shells distortedunequally by stretching. See Clause 2S3.7.6 for design for hydrotesting in the horizontalposition.

2S3.7.6 Horizontal cylindrical vessels under combined loading Additionally, thedesign shall cater for axial buckling during hydro stretching and for modified shell shape.

2S3.8 THICK-WALLED CYLINDRICAL AND SPHERICAL VESSELS SUBJECTTO INTERNAL PRESSURE Clause 3.8 of AS 1210 does not apply.

2S3.9 CYLINDRICAL AND SPHERICAL SHELLS SUBJECT TO EXTERNALPRESSURE Clause 3.9 of AS 1210 applies with the following modifications.

2S3.9.2 Notation The value off shall be taken as that given in AS 1210, Clause 3.9.2.

2S3.9.6.2 Form of stiffening rings Circumferential rings are permitted as stiffeners orsupports of cold-stretched shells provided the rings are complete so that no openings ornotches are formed which cause localized strain in the shell or ring in excess of 10%. Anyopenings or notches in the rings should be located clear of joints in the ring and shall besmooth. The joints in the ring itself shall be full penetration welds, subject to radiographybefore stretching and to close visual examination after stretching, where accessible. Toesof welds on the shell plate, of welds attaching the ring to shell, shall blend smoothly andbe free of undercut. See Clause 2S3.25.

2S3.12 DISHED ENDS SUBJECT TO INTERNAL PRESSURE Clause 3.12 ofAS 1210 applies with the following addition.

2S3.12.1 General Ends shall be spherical or ellipsoidal with an outside major to minoraxis ratio not greater than 2:1.

CLAUSES 2S3.13 TO 2S3.17 INCLUSIVE Clauses 3.13 to 3.17 of AS 1210 do notapply to cold-stretched vessels.

2S3.18 OPENINGS AND REINFORCEMENTS Clause 3.18 of AS 1210 applies withthe following additions and modifications:

NOTE: Allowance should be made for possible distortion of the opening and nozzle, e.g. by useof reduced value off.

2S3.18.5 Location of openings Any opening exceeding 325 mm diameter shall belocated in the end of the vessel and shall be concentric with the vessel shell except whereproof is provided that the local strain in the end does not exceed 10%. Additionally,designs should aim to have all attachments fitted to the vessel ends wherever this ispracticable.

2S3.18.6 Unreinforced openings Unreinforced openings shall comply withClause S3.18.6 of AS 1210 Supplement 1.

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11 AS 1210 Supp2 — 1999

Nozzles should be of the same type of material as the shell. Integral reinforcement of theopening by increased nozzle wall thickness is preferred in all cases. Doubling plates orpads (or reinforcing rings around the nozzle) should be avoided where practicable toprevent excessive local strain in the shell near the pad.

2S3.18.7 Reinforcement of single openings in shells and dished endsFor cold-stretched vessels the design of openings and reinforcements shall be on the areareplacement method (i.e. plastic design) assuming the shell and nozzle have an‘ f ’ valuenot in excess of that in Clause S3.3.1.1.

2S3.19 CONNECTIONS AND BRANCHES Clause 3.19 of AS 1210 applies with thefollowing addition.

2S3.19.3.4 Tell-tale holes Tell-tale holes are not required in internal doubling orwrapper plates where heat treatment is not required and avoidance of contentcontamination is necessary.

2S3.23 JACKETED VESSELS Clause 3.23 of AS 1210 applies but not for partiallyjacketed cold-stretched vessels.

2S3.24 VESSEL SUPPORTS Clause 3.24 of AS 1210 applies in conjunction withClause 2S3.25.

2S3.25 ATTACHED STRUCTURES AND EQUIPMENT Clause 3.25 of AS 1210applies with the following additions.

2S3.25.4 Attachment for cold-stretched vesselsRings and similar structural partsattached to cold-stretched shells or ends shall comply with the following:

(a) Clause 3.9 of AS 1210 for rings designed for prevention of buckling.

(b) Clause 3.24.4 of AS 1210, AS 3990, or other appropriate reference for supportsusing design strength (‘ f’ ) as in AS 1210 or AS 1210 Supplement 1 (as desired) at adesign temperature equal to—

(i) at least 20°C, to ensure adequacy at the combined pressure and loadingduring the hydro or other pressure test; and

(ii) the highest temperature of liquid adjacent to the vessel part under coincidentservice pressure and load conditions, e.g. for cryogenic transportable vessels,supports and internal stiffeners may be designed for the required‘G’loading, with ‘ f ’ at the boiling point of the contained gas at the safety valvepressure setting.

(c) As an alternative to Item (b), comply with AS 4100 but with yield strength equal tothe 1% proof strength of the steel at the temperatures specified in Item (b).

(d) Calculations for support rings shall include determination of transverse bendingstress in the ring flange.

(e) Welds attaching rings to the shell shall be continuous on both sides of the web witha minimum total throat thickness equal to the web thickness. See Clause 2S3.19.3.4

2S3.26 TRANSPORTABLE VESSELS Clause 3.26 of AS 1210 applies with thefollowing additions.

2S3.26.3.1 Class of construction Transportable vessels for the carriage of products byroad, rail or sea can be manufactured as cold-stretched stainless steel vessels shall beClass 1S construction in place of Class 1 and Class 2SA in place of Class 2A and 2B.

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AS 1210 Supp2 — 1999 12

(c) The design shall be assessed and comply with the fatigue requirements ofClause 2S3.2.8 taking into account actual shape of welds permitted, local distortion,location of attachments and the additional transport loads. This shall also apply tothe supports.

(d) Before use with lethal or very harmful fluids (see AS 4343), the design shall beproven by operation of a vessel fully representative of the design and construction,for a service period of at least one year using fluid other than lethal or veryharmful; or by accelerated fatigue testing a full size vessel under equivalent loadingand cycling.

(e) For ISO tank container type pressure vessels, the total assembly of the frame andvessel shall meet the requirements of the relevant authority for the particular modeof transport to be carried by sea and the relevant rail authority for containers to becarried by rail.

(f) For vessels covered by Item (e), the design strength‘ f’ used in the design of shellsand ends shall comply with IMDG code; and the thickness of the shell and ends (orthe combined wall thickness of jacket and the shell or ends of a vacuum insulatedvessel)tmin shall be not less than—

(i) 5 mm;

(ii) that required in Clause 3.4.3; and

(iii) for shell and ends over 1000 mm diameter in contact with the pressurizedcontents not less than that given by Equation 2S3.26:

. . . 2S3.26tmin = C3

Rm × Awhere

A = guaranteed minimum percentage elongation (L = 5d)

C = 107 for vessels≤1.8 m diameter

C = 128 for vessels >1.8 m diameter

C = 64 for vacuum insulated vessels≤1.8 m diameter

C = 85 for vacuum insulated vessels >1.8 m diameter

Rm = ‘guaranteed’ minimum tensile strength at design temperature, inmegapascals

tmin = minimum thickness of shell and ends at design temperature, inmillimetres

(g) The type of material, its design strength, thickness and any insulation shall besufficient to give a period of at least 15 minutes from the time of fire engulfment torupture of the shell. The rupture of the shell shall not result in fragmentation.Supporting calculations or tests shall be made but are not required for Item (h)(i) or(ii) where the jacket metal is of steel.

Calculations shall be based on any insulation provided being intact except for lossof any vacuum, uninsulated gas backed surfaces reaching 650°C, the pressureequalling the design pressure, and reasonably reliable short-term mean creep rupturedata of the steel at 650°C.

(h) Transportable non-vacuum, cold-stretched vessels shall have external protectionagainst impact at least equivalent to—

(i) 2 mm metal jacket with 100 mm powder or fibre insulation;

(ii) 2.5 mm metal jacket with multi-layer (super) insulation; or

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13 AS 1210 Supp2 — 1999

(iii) 1 mm metal jacket (see below for lethal, toxic and flammable contents) with100 mm rigid fire retardant foam.

NOTE: Insulation for impact may also be used for fire protection.

For lethal or very harmful (toxic or flammable) contents, the combined thickness of themetal jacket and the vessel wall shall be at least 9 mm. The minimum thickness of themetal jacket shall be 2 mm.

For harmful or non-harmful contents, the combined thickness of the metal jacket andvessel wall shall be at least 7 mm.

CLAUSES 2S3.27 TO 2S3.32 INCLUSIVE Clauses 3.27 to 3.32 of AS 1210 do notapply to cold-stretched vessels.

2S3.33 VESSELS WITH INCREASED DESIGN STRENGTH AT LOW TEMPERA-TURE Clause 3.33 of AS 1210 applies with the provision that alternative reliable andconservative strength values for cold-stretched steel may be used where fully justified atdesign verification.

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AS 1210 Supp2 — 1999 14

S E C T I O N 2 S 4 M A N U F A C T U R E

Section 4 of AS 1210 shall apply with the following additions and modifications toparticular Clauses.

2S4.2 WELDED CONSTRUCTION Clause 4.2 of AS 1210 applies with the followingaddition and modification.

2S4.2.1 General welding requirements Butt weld reinforcement limits to AS 1210and AS 4458 apply, but lower values are recommended for longitudinal type welds.Dressing of welds is only required where necessary to meet these limits or the shaperequired by fatigue design.

2S4.5 BRAZED CONSTRUCTION Brazing shall not be used on main shells and endsof cold-stretched vessels.

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15 AS 1210 Supp2 — 1999

S E C T I O N 2 S 5 T E S T I N G A N DQ U A L I F I C A T I O N

Section 5 of AS 1210 shall apply, with the following additions and modifications toparticular Clauses.

2S5.3 NON-DESTRUCTIVE EXAMINATION Clause 5.3 of AS 1210 applies withthe following additions:

Each vessel after cold-stretching shall be examined at accessible surfaces at thecircumferential rings (and other areas of potential high localized strain) to ensure localstrain has not exceeded the 10% limit.

Radiographic examination shall be done before the hydrostatic test. In Class 1S vessels,longitudinal and circumferential type welds shall have 100% radiographic examination. InClass 2SA vessels longitudinal type welds shall have 100% radiographic examination andcircumferential type welds shall have at least 10% radiographic examination. All tee jointsshall be radiographed.

Penetrant examination shall be done after the hydrostatic test at areas which are accessibleand the local strain may exceed 5%.

2S5.10 HYDROSTATIC TESTS Clause 5.10 of AS 1210 applies with the followingaddition and modification.

2S5.10.2.1 Hydrostatic test—Single wall vessels designed for internal pressure

The vessel shall be hydrostatically tested and cold-stretched at the higher pressurecalculated in accordance with Equations 2S5.10.2.1(1) and 2S5.10.2.1(2).

. . . 2S5.10.2.1(1)ph 1.5 p ×fh

f

. . . 2S5.10.2.1(2)ph = 1.5fh

f(p + hgρ 10−6) − hh g ρh 10−6

where

ph = hydrostatic test pressure at the top of the vessel, in megapascals

p = design pressure of the vessel at the top of the vessel, in megapascals

fh/f = lowest ratio (for the materials of which the vessel is constructed) of—

design strength at test temperature, MPadesign strength at design temperature, MPa

(Values to be taken from Table 2S3.3.1 or as used in the design.)

h = maximum head of liquid in service, in metres

hh = actual head of test liquid, in metres

ρ = density of liquid in service, in kilograms per cubic metre

ρh = density of test liquid, in kilograms per cubic metre

g = 9.81, in metres per second per second

The test pressure shall be maintained until the measured strain rate does not exceed 0.1%per hour.

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AS 1210 Supp2 — 1999 16

The total circumferential strain shall be determined during pressuring and depressuring bymeasuring the general increase in circumference of at least one strake of each nominalthickness at positions which are judged to have minimum restraint.

NOTE: In a vessel which does not have circumferential stiffening, the above mentionedlocations will normally be at the mid-length of the shell strakes having the lowest value of platethickness multiplied by proof strength (from the steel makers certificates). To facilitatemeasurement this strake may be located at the bottom of large vessels tested in the verticalposition.

The total permanent circumferential strain based on the general increase in circumferenceshall not exceed 5 percent. See also Clause 2S5.4.

In the event the required test pressure is not reached at 5.2% total strain, the vessel shall

be modified, rejected or derated to a design pressure equal to times the maximum test11.5

pressure reached at 5.2% total strain.

2S5.11 PNEUMATIC TESTS Clause 5.11 of AS 1210 applies with the followingmodification:

Pneumatic cold-stretching and testing shall not be used unless done in a safe explosionresistant enclosure or under equivalent conditions and in accordance with a fullydocumented procedure which will ensure no injury in the event of unexpected failure.

2S5.17 SPECIAL EXAMINATIONS AND TESTS Clause 5.17 of AS 1210 applieswith the following addition:

A full scale test shall be made to ensure the transverse strain at the toes of fillet weldsattaching a circumferential ring to the shell are within strain limits. Measurements tocheck this strain shall be taken after completion of the cold-stretch/hydrostatic test at apoint located on the vessel wall showing maximum curvature from the original shape.This location may be determined by visual inspection and shall account for any weldingdistortion which may be present before cold stretching is carried out. This test may bemade on one completed vessel with the highest total circumferential strain or may bemade on a representative test specimen made of the same materials and thickness.

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17 AS 1210 Supp2 — 1999

S E C T I O N 2 S 6 A S S U R A N C E O F P R O D U C TQ U A L I T Y

Section 6 of AS 1210 shall apply.

S E C T I O N 2 S 7 M A R K I N G

Section 7 of AS 1210 shall apply, with the following additions and modifications:

2S7.1 MARKING REQUIRED Clause 7.1 of AS 1210 applies with the followingaddition:

In addition to the marking required by Clause 7.1 of AS 1210, each vessel shall bemarked with the maximum permanent strain actually measured e.g.‘1.2% max coldstretch’ .

2S7.7 REPORTS The Manufacturers Data Report (see AS 4458) shall show themarking specified in Clause 2S7.1 and the location of this strain.

A record of the pressurizing sequence including measured pressures and circumferentialmeasurements versus time and strain rate shall be kept by the manufacturer.

S E C T I O N 2 S 8 P R O T E C T I V E D E V I C E S A N DO T H E R F I T T I N G S

Section 8 of AS 1210 shall apply.

S E C T I O N 2 S 9 P R O V I S I O N S F O R D E S P A T C H

Section 9 of AS 1210 shall apply.

S E C T I O N 2 S 1 0 N O N - M E T A L L I C V E S S E L S

Section 10 does not apply, except Clause 10.2(a) of AS 1210 for non-metallic componentsof cold-stretched vessels.

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AS 1210 Supp2 — 1999 18

APPENDICES

The Appendices of AS 1210 shall apply with the following addition to the particularAppendix.

APPENDIX 2SR

LIST OF REFERENCED DOCUMENTS

Appendix R of AS 1210 shall apply with the following addition:

AS4343 Pressure equipment—Hazard levels

ISO9328 Steel plates and strip for pressure purposes—Technical delivery conditions9328-5 Part 5: Austenitic steels

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