AS 1228-1997

1 - AS 1228-1997 PRESSURE EQUIPMENT - BOILERS
4 - PREFACE
5 - CONTENTS
7 - SECTION 1 SCOPE AND GENERAL
7 - 1.1 SCOPE
7 - 1.2 APPLICATION
7 - 1.3 REFERENCED DOCUMENTS
7 - 1.4 DEFINITIONS
7 - 1.4.1 Actual thickness
7 - 1.4.2 Calculation pressure
8 - 1.4.3 Design temperature
8 - 1.4.4 Design lifetime
8 - 1.4.5 Design pressure
8 - 1.4.6 Design strength
8 - 1.4.7 Drum
8 - 1.4.8 Electrode boiler
8 - 1.4.9 Element boiler
8 - 1.4.10 Fire-tube boiler
8 - 1.4.11 Forced or assisted circulation boiler
8 - 1.4.12 Header
8 - 1.4.13 Integral piping
9 - 1.4.14 Miscellaneous boilers
9 - 1.4.15 Natural circulation boiler
9 - 1.4.16 Nominal thickness
9 - 1.4.17 Once-through boiler
9 - 1.4.18 Tube
9 - 1.4.19 Water-tube boiler
9 - 1.4.20 Organic fluid heater and vaporizer
13 - 1.5 DESIGNATION
13 - 1.6 VALVES, FITTINGS AND BOILER INSTALLATION
13 - 1.7 RATING
13 - 1.8 RESPONSIBILITIES
14 - SECTION 2 MATERIALS AND DESIGN STRENGTHS
14 - 2.1 MATERIALS
14 - 2.1.1 General
14 - 2.1.2 Material identification
14 - 2.1.3 Welding materials
14 - 2.1.4 Prohibition of use of certain materials
14 - 2.1.5 Alternative material specifications
14 - 2.1.6 Use of structural or similar quality steels
15 - 2.1.7 Specifically tested materials
40 - 2.2 DESIGN STRENGTHS
40 - 2.2.1 General
40 - 2.2.2 Carbon and carbon-manganese steels
40 - 2.2.3 Alloy steels
40 - 2.2.4 Cast steels
40 - 2.2.5 Design temperature for water-tube boilers
42 - 2.2.6 Design temperature for tube and tube plates for fire-tube boilers
45 - 2.3 DESIGN LIFETIME
46 - SECTION 3 DESIGN
46 - 3.1 DESIGN CRITERIA
46 - 3.1.1 General
46 - 3.2 CYLINDRICAL SHELLS, DRUMS AND HEADERS SUBJECT TO INTERNAL PRESSURE
46 - 3.2.1 Shell thickness
46 - 3.2.2 Minimum thickness
47 - 3.2.3 Fire-tube and miscellaneous boilers
47 - 3.2.4 Longitudinal ligament efficiency
49 - 3.2.5 Equivalent longitudinal ligament efficiency for drilling on a diagonal line
51 - 3.2.6 Circumferential ligaments
51 - 3.2.7 Combined stresses in drum or header shells
58 - 3.2.8 Drum stress due to supports
58 - 3.2.9 Other drum stresses
58 - 3.2.10 Openings in cylindrical shells
60 - 3.2.11 Unreinforced openings
61 - 3.2.12 Reinforcement of single openings in shells
62 - 3.2.13 Limits of available reinforcement
65 - 3.2.14 Strength of reinforcement
65 - 3.2.15 Reinforcement of multiple openings
66 - 3.2.16 Openings in furnaces of fire-tube boilers
66 - 3.2.17 Fillet welds attaching parts, compensating plates and cylindrical shells of boilers
67 - 3.3 DISHED ENDS SUBJECT TO INTERNAL PRESSURE
67 - 3.3.1 General
67 - 3.3.2 Required shape
68 - 3.3.3 Thickness
70 - 3.3.4 Openings in dished ends
73 - 3.3.5 Dished and flanged crowns for vertical boilers
75 - 3.4 RECTANGULAR SECTION HEADERS
75 - 3.4.1 Straight rectangular headers
78 - 3.4.2 Rectangular headers other than straight
78 - 3.5 HEADER ENDS
78 - 3.5.1 General
78 - 3.5.2 Ends attached by welding
79 - 3.5.3 Ends attached by bolting
79 - 3.5.4 Reinforcement of openings in flat ends
81 - 3.6 PRESSURE PARTS OF IRREGULAR SHAPE
81 - 3.6.1 General
81 - 3.6.2 Test pressure
81 - 3.7 TUBES AND INTEGRAL PIPES
81 - 3.7.1 Minimum thickness subjected to internal pressure
82 - 3.7.2 Tubes subject to external pressure
82 - 3.7.3 Bending of boiler, superheater, reheater, and economizer tubes
82 - 3.7.4 Flexibility of piping systems
84 - 3.8 STRUCTURAL ATTACHMENTS TO TUBES
84 - 3.8.1 Welding of attachments
84 - 3.8.2 Maximum thickness of attachment
84 - 3.8.3 Intensity of radial loading
85 - 3.8.4 Maximum force due to radial loading
89 - 3.9 INSPECTION OPENINGS
89 - 3.9.1 Access openings water-tube and fire-tube boilers
89 - 3.9.2 Externally-fitted cover plates
89 - 3.9.3 Internally fitted doors
92 - 3.9.4 Openings in flat plates of fire-tube boilers
93 - 3.9.5 Inspection and cleaning for fire-tube and miscellaneous boilers
98 - 3.10 STAYS, STIFFENERS AND SUPPORTED SURFACES FOR FIRE-TUBE AND MISCELLANEOUS BOILERS
98 - 3.10.1 End plates
98 - 3.10.2 Breathing spaces
111 - 3.10.3 Stayed flat surfaces
112 - 3.10.4 Flat crown plates for vertical boilers
113 - 3.10.5 Girders for fire box and reversal chamber crowns
116 - 3.10.6 Stays for fire boxes, circular furnaces and reversal chambers
126 - 3.10.7 Firebox crown stays and stiffeners for loco-type boilers
126 - 3.10.8 Longitudinal bar stays
126 - 3.10.9 Loads on stay tubes and bar stays
126 - 3.10.10 Gusset and link stays (corner stays)
130 - 3.11 TUBES AND TUBE PLATES FOR FIRE-TUBE AND MISCELLANEOUS BOILER
130 - 3.11.1 Stay tubes and plain tubes
130 - 3.11.2 Pitch of tubes
133 - 3.11.3 Thickness of tube plates within tube nests
133 - 3.11.4 Horizontal shelves of tube plates forming part of the shell
133 - 3.11.5 Horizontal tube nests in vertical boilers
134 - 3.12 FURNACES, REVERSAL CHAMBERS AND FIREBOXES OF CYLINDRICAL FORM SUBJECT TO EXTERNAL PRESSURE
134 - 3.12.1 Furnaces
137 - 3.12.2 Circular reversal chambers
137 - 3.12.3 Fireboxes and associated components
147 - 3.13 BOILER SETTINGS
147 - 3.14 BRANCHES AND STUDDED CONNECTIONS
147 - 3.14.1 Thickness
147 - 3.14.2 Forms of connections
148 - 3.14.3 Seatings for mountings
151 - 3.14.4 Integral piping branches
171 - SECTION 4 MANUFACTURE AND WORKMANSHIP
171 - 4.1 PRESSURE PARTS
171 - 4.1.1 General
171 - 4.1.2 Cylindrical shells and drums
171 - 4.1.3 Welded construction
172 - 4.1.4 Headers and similar pressure parts
172 - 4.1.5 Plain tubes and stay tubes for fire-tube and miscellaneous boilers
173 - 4.1.6 Attachment of tubes - General
173 - 4.1.7 Furnaces for fire-tube and miscellaneous boilers
173 - 4.1.8 Fireboxes for fire-tube and miscellaneous boilers
178 - 4.1.9 Stays for fire tube and miscellaneous boilers
179 - 4.2 WELDING
179 - 4.2.1 General
179 - 4.2.2 Welds of main joints
179 - 4.2.3 Welding of pipes and tubes
180 - SECTION 5 INSPECTION AND TESTING
180 - 5.1 GENERAL
180 - 5.2 NON-DESTRUCTIVE EXAMINATION
180 - 5.3 TEST PLATES AND MECHANICAL TESTS OF PRODUCTION WELDS
180 - 5.3.1 Provision of test plates
181 - 5.4 HYDROSTATIC TESTS
181 - 5.4.1 General requirements
181 - 5.4.2 Test pressure
181 - 5.4.3 Component testing
182 - 5.4.4 Requirements for once-through boilers
182 - 5.4.5 Hydrostatic test procedure
184 - SECTION 6 DOCUMENTATION AND MARKING
184 - 6.1 DRAWINGS, DOCUMENTS, AND DATA SHEETS
184 - 6.2 CERTIFICATES
184 - 6.3 MARKING
184 - 6.3.1 General
184 - 6.3.2 Marking required
185 - SECTION 7 MISCELLANEOUS BOILERS AND COIL-TYPE FORCED CIRCULATION BOILERS
185 - 7.1 ELECTRIC BOILERS
185 - 7.1.1 General
185 - 7.1.2 Electricity supply
185 - 7.1.3 Load adjustment
185 - 7.1.4 Current balance
185 - 7.1.5 Electrodes, elements and internal parts
186 - 7.1.6 Pressure and temperature control
186 - 7.1.7 Hydrostatic tests
186 - 7.1.8 Access
186 - 7.2 CAST IRON BOILERS
186 - 7.2.1 General
186 - 7.2.2 Maximum design pressure
186 - 7.2.3 Maximum design temperature
186 - 7.2.4 Materials
186 - 7.2.5 Witnessing of bursting tests
186 - 7.3 MINIATURE BOILERS
186 - 7.3.1 General
187 - 7.3.2 Designation
187 - 7.3.3 Design and construction
187 - 7.3.4 Materials
187 - 7.3.5 Inspection openings
187 - 7.3.6 Valves, gauges and other fittings
187 - 7.4 COIL-TYPE FORCED CIRCULATION BOILERS
187 - 7.4.1 General
187 - 7.4.2 Limitations
188 - 7.4.3 Requirements
188 - 7.5 ORGANIC FLUID HEATERS AND VAPORIZERS
188 - 7.5.1 General
188 - 7.5.2 Materials
188 - 7.5.3 Design
188 - 7.5.4 Valves and fittings
188 - 7.6 WATER MANAGEMENT SYSTEMS
189 - APPENDIX A - LIST OF REFERENCED DOCUMENTS
192 - APPENDIX B - EXAMPLE OF PRINCIPAL INTEGRAL WATER-TUBE BOILER PIPEWORK COVERED BY THIS STANDARD
193 - APPENDIX C - INFORMATION TO BE SUPPLIED BY THE PURCHASER AND THE MANUFACTURER
193 - C1 INFORMATION TO BE SUPPLIED BY THE PURCHASER
194 - C2 INFORMATION TO BE SUPPLIED BY THE MANUFACTURER
195 - APPENDIX D - DERIVATION OF MATERIAL DESIGN STRENGTH
195 - D1 GENERAL
195 - D2 NOTATION
195 - D3 TIME-INDEPENDENT DESIGN STRENGTH
195 - D3.1 General
196 - D3.2 Carbon, carbon-manganese, and low alloy steels
196 - D3.3 Austenitic steels
197 - D4 TIME-DEPENDENT DESIGN STRENGTHS
198 - APPENDIX E - CALCULATION OF TUBEPLATE TEMPERATURES
198 - E1 GENERAL
198 - E2 NOTATION
199 - E3 CALCULATION METHOD
199 - E3.1 Radiation coefficients
200 - E3.2 Convection coefficients
200 - E3.3 Weighted average gas-side heat transfer coefficient
201 - E3.4 Tubeplate thermal conductance
201 - E3.5 Water-side heat transfer
201 - E3.6 Tubeplate temperatures
201 - E4 EXAMPLE OF A CALCULATION
201 - E4.1 Design data assumed
202 - E4.2 Calculation of radiation coefficient
202 - E4.3 Calculation of convection coefficients
202 - E4.4 Calculation of weighted average gas-side heat transfer coefficient
202 - E4.5 Calculation of tube plate thermal conductance
203 - E4.6 Calculation of tube plate temperatures
213 - BIBLIOGRAPHY
214 - APPENDIX F - ANALYTICAL DESIGN METHOD FOR REINFORCEMENT OF OPENINGS ALTERNATIVE TO THE DESIGN METHOD SHOWN IN CLAUSE 3.2.10
214 - F1 GENERAL
216 - F2 LIMITS OF APPLICATION
216 - F3 DESIGN METHOD FOR ISOLATED OPENINGS OR BRANCHES
218 - F4 EXTENT OF REINFORCEMENT
218 - F5 DESIGN METHOD FOR GROUPS OF OPENINGS OR BRANCHES
224 - APPENDIX G - EXAMPLE OF MANUFACTURER'S REPORT

This Standard sets out requirements for materials, design, construction, inspection and testing of boilers as defined in AS/NZS 1200. Specifically applies to design and construction of boilers including superheaters, reheaters and economizers. Incorporates the existing AS 1228-1990, Boilers-Water-tube, and AS 1797-1986, Boilers-Fire-tube, shell and miscellaneous, into one document. This incorporation eliminates duplication and possible conflict when considering the core documents for the Pressure Equipment suite of Standards.

This Standard sets out requirements for materials, design, construction, inspection and testing of boilers as defined in AS/NZS 1200.NOTE: The Scope of this Standard covers requirements for cast iron in addition to welded boilers inclusive of vapour-generating and hot fluid units subject to internal vapour or liquid pressure. Other forms of construction should be by agreement between the parties concerned.This Standard specifically applies to design and construction of boilers including superheaters, reheaters and economizers. It also applies to all pressure parts containing fluid up to and including the valves separating the pressure parts from -(a) steam piping to and from other equipment; (b) water piping to and from other equipment; (c) drain piping; (d) the surrounding atmosphere, except that for safety valves, their vent piping to the atmosphere is also covered; and (e) for equipment such as reheaters which may not incorporate valves at their supply and return connection points, the Standard applies to the equipment included between the inlet to the inlet header and the outlet from the outlet header of such equipment.

First published in Australia in part as AS B31-1931.
AS CB1 first published 1932.
Redated 1932.
Redated 1939.
Second edition 1942.
Redated 1950.
AS CB1.5 first published 1951.
AS CB1-1950 redated 1952.
AS B31-1931 incorporated into AS CB1-1952 as Amendment.
AS CB1-1952 redated 1954.
AS CB1.5-1951 redated 1954.
AS CB1-1954 revised and redesignated in part as AS CB1.1-1962 and AS 1228-1972.
AS CB1.5-1954 revised and redesignated in part as AS 1228-1972.
AS CB1.1-1962 revised and redesignated as AS 1797-1975 and AS 1797-1978.
Second edition AS 1228-1980.
Third edition AS 1797-1981.
Third edition AS 1228-1984.
Fourth edition AS 1797-1986.
Fourth edition AS 1228-1990.
AS 1797-1986 and AS 1228-1990 revised, amagamated and designated AS 1228-1997.