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103343 ASNZS1252.1 Public Comment.doc - 09/03/2016 9:29:19

COMMITTEE ME-029

DR AS/NZS 1252.1:2016

(Project ID: 103343)

Draft for Public Comment

Australian/New Zealand Standard

LIABLE TO ALTERATION—DO NOT USE AS A STANDARD

BEGINNING DATEFOR COMMENT:

16 March 2016

CLOSING DATEFOR COMMENT:

18 May 2016

Important: The procedure for public comment has changed – please

read the instructions on the inside cover of this document .

High-strength steel bolt assemblies comprising bolts,nuts and washers for structural engineeringPart 1: Technical requirements(Revision of AS/NZS 1252:1996)

COPYRIGHT

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The committee responsible for the issue of this draft comprised representatives of organizationsinterested in the subject matter of the proposed Standard. These organizations are listed on theinside back cover.

Comments are invited on the technical content, wording and general arrangement of the draft.The method for submission of comment on this document is to register and fill in an online form viaStandards Hub Website. Instructions and examples of comment submission are available on the website. . P lease use the fol lowing link—

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The coordination of the requirements of this draft with those of any related Standards is of particularimportance and you are invited to point out any areas where this may be necessary.

Please provide supporting reasons and suggested wording for each comment. Where you considerthat specific content is too simplistic, too complex or too detailed please provide an alternative.

If the draft is acceptable without change, an acknowledgment to this effect would be appreciated.

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Normally no acknowledgment of comment is sent. All comments received via the Standards HubWebsite by the due date will be reviewed and considered by the relevant drafting committee. Wecannot guarantee that comments submitted in other forms will be considered along with thosesubmitted via the Standards Hub online form. Where appropriate, changes will be incorporatedbefore the Standard is formally approved.

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STANDARDS AUSTRALIA/STANDARDS NEW ZEALAND

Committee ME-029—Fasteners

DRAFT


High-strength steel bolt assemblies comprising bolts, nuts and washers forstructural engineering

Part 1: Technical requirements

(Revision of AS/NZS 1252:1996)

(To be AS/NZS 1252.1:201X)

Comment on the draft is invited from people and organizations concerned with this subject.

It would be appreciated if those submitting comment would follow the guidelines given on

the inside front cover.

Important: The procedure for public comment has changed – pleaseread the instructions on the inside cover of this document

This document is a draft Australian/New Zealand Standard only and is liable to alteration in

the light of comment received. It is not to be regarded as an Australian/New Zealand

Standard until finally issued as such by Standards Australia/Standards New Zealand.

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DRAFT ONLY 2 DRAFT ONLY


PREFACE

This Standard was prepared by the Joint Standards Australia/Standards New Zealand

Committee ME-029, Fasteners, to supersede AS/NZS 1252:1996, High-strength steel boltswith associated nuts and washers for structural engineering .

The objective of this Standard is to provide manufacturers of high-strength steel bolt

assemblies with requirements and tests to ensure that such assemblies are suitable for bolted

connections in steelwork construction, consistent with the steel design Standards AS 4100

and NZS 3404.

The major technical changes incorporated in this edition relate to updated testing and

conformity requirements and the inclusion of a specific nominated European fastener

Standard as a ‘deemed to satisfy’ alternative product. This latter aspect is designed to

improve procurement outcomes in the Australian marketplace. The specific changes include

the following:

(a) Updating and expansion of definitions to align, where relevant, with ISO definitions.

(b) Revision of dimensions to align with ISO requirements.

(c) Nomination of bolt assemblies to EN 14399-3 Type HR property class 8.8 as an

alternative assembly type.

(d) Addition of the k-class definition and testing requirements, which defines the torque-

tension relationship during tightening of the bolt assemblies.

NOTE: This is designed to facilitate use of torque as a tightening method if writ ten into a

future revision of AS 4100 or NZS 3404.

(e) New Section 5 specifically defining the performance requirements of the bolt

assembly. This is supported with an updated normative appendix, Appendix D, whichsets out bolt assembly tests.

(f) New Section 6 on identification, certification and testing.

(g) Inclusion of the M12 product.

(h) New informative Appendix A, describing the differences between the European ‘HR’

and ‘HV’ bolt types.

(i) New Appendix B on product conformity.

This Standard is based on and, except for the marking requirements for the nuts and bolts, is

technically equivalent to, the following withdrawn ISO Standards for the relevant property

class:

ISO

4775:1984 Hexagon nuts for high-strength structural bolting with large width across

flats—Product grade B—Property classes 8 and 10

7411:1984 Hexagon bolts for high-strength structural bolting with large width across

flats (thread lengths according to ISO 888)—Product grade C—Property

classes 8.8 and 10.9

7415:1984 Plain washers for high-strength structural bolting, hardened and tempered

Statements expressed in mandatory terms in notes to tables are deemed to be requirements

of this Standard.

The terms ‘normative’ and ‘informative’ have been used in this Standard to define the

application of the appendix to which they apply. A ‘normative’ appendix is an integral part

of a Standard, whereas an ‘informative’ appendix is only for information and guidance.

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This revision is compatible with AS 4100—1998 incorporating Amendment No.1 (2012).

NOTE: It is the intent of the committee to replace this Standard with the EN 14399 series, which

will require further amendment of AS 4100.

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CONTENTS

Page

SECTION 1 SCOPE AND GENERAL

1.1 SCOPE ......................................................................................................................... 5

1.2 APPLICATION ........................................................................................................... 5

1.3 REFERENCED DOCUMENTS ................................................................................... 5

1.4 DEFINITIONS............................................................................................................. 6

1.5 ALTERNATIVE ASSEMBLY TYPE ......................................................................... 9

1.6 MARKING .................................................................................................................. 9

1.7 DESIGNATION ........................................................................................................ 10

1.8 PRODUCT REQUIREMENTS .................................................................................. 12

SECTION 2 HIGH-STRENGTH STEEL BOLTS2.1 METHOD OF MANUFACTURE .............................................................................. 13

2.2 SHAPE, DIMENSIONS AND FINISH ...................................................................... 13

2.3 MATERIALS AND MECHANICAL PROPERTIES................................................. 15

SECTION 3 HIGH-STRENGTH STEEL NUTS

3.1 METHOD OF MANUFACTURE .............................................................................. 22

3.2 SHAPE, DIMENSIONS AND FINISH ...................................................................... 22

3.3 MATERIAL AND MECHANICAL PROPERTIES ................................................... 23

SECTION 4 FLAT ROUND WASHERS

4.1 METHOD OF MANUFACTURE .............................................................................. 26

4.2 SHAPE, DIMENSIONS AND FINISH ...................................................................... 264.3 MATERIAL AND MECHANICAL PROPERTIES ................................................... 26

SECTION 5 BOLT ASSEMBLIES

5.1 GENERAL ................................................................................................................. 28

5.2 FUNCTIONAL CHARACTERISTICS OF THE BOLT ASSEMBLY ...................... 28

SECTION 6 IDENTIFICATION, CERTIFICATION AND TESTING

6.1 GENERAL ................................................................................................................. 30

6.2 IDENTIFICATION .................................................................................................... 30

6.3 TESTING AND TEST REPORTS ............................................................................. 30

6.4 TESTING OF DIMENSIONAL REQUIREMENTS .................................................. 31

6.5 TESTING OF MECHANICAL CHARACTERISTICS ............................................. 32

6.6 TESTING OF FUNCTIONAL CHARACTERISTICS............................................... 34

APPENDICES

A A DISCUSSION OF THE BASIS FOR ‘HR’ AND ‘HV’ SYSTEM TYPES

IN THE EN 14399 SERIES ....................................................................................... 35

B PRODUCT CONFORMITY ...................................................................................... 37

C PURCHASING GUIDELINES .................................................................................. 42

D ASSEMBLY TESTING FOR FASTENERS .............................................................. 44

E SQUARE TAPER WASHERS .................................................................................. 48

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STANDARDS AUSTRALIA/STANDARDS NEW ZEALAND


High-strength steel bolt assemblies comprising bolts, nuts and washersfor structural engineering

Part 1: Technical requirements

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 the dimensional, material and marking requirements for steel bolt

assemblies comprising steel bolts of property class 8.8, steel nuts of property class 8 with

ISO metric coarse pitch series threads, in diameters from 12 mm to 36 mm, and associated

hardened and tempered steel washers intended for use in steel structures. The bolt

assemblies are intended to be fully tensioned but may also be used in a snug tight condition

or where designed to be partially tensioned. This Standard also sets out tests to verify the

suitability of high-strength bolt/nut/washer assemblies for tensioning (preloading) for

bolted connections in steelwork construction.

1.2 APPLICATION

Bolts, nuts and washers shall comply with the requirements of this Section and the

following Sections as applicable:(a) Bolts ............................................ ............................................ .................... Section 2.

(b) Nuts ....................................... ............................................ .......................... Section 3.

(c) Washers ...................................... ............................................ ..................... Section 4.

(d) Assemblies ...................................... ............................................ ................ Section 5.

(e) Identification, certification and testing .......................................... ............... Section 6.

1.3 REFERENCED DOCUMENTS

The following documents are referred to in this Standard:

AS

1214 Hot-dip galvanized coatings on threaded fasteners (ISO metric coarse thread

series)

1275 Metric screw threads for fasteners

1815.1 Metallic materials—Rockwell hardness test

Method 1: Test method (scales A, B, C, D, E, F, G, H, K, N, T)

1817.1 Metallic materials—Vickers hardness test

Method 1: Test method (ISO 6507-1:1997, MOD)

1897 Electroplated coatings on threaded components (metric coarse series)4100 Steel structures

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AS

4291 Mechanical properties of fasteners made of carbon steel and alloy steel

4291.1 Part 1: Bolts, screws and studs

AS/NZS

4291 Mechanical properties of fasteners4291.2 Part 2: Nuts with specified proof load values—Coarse thread

4680 Hot-dip galvanized (zinc) coatings on fabricated ferrous articles

NZS

3404 Steel structures

ISO

4042 Fasteners—Electroplated coatings

6157 Fasteners—Surface discontinuities

6157-1 Part 1: Bolts, screws and studs for general requirements

6157-2 Part 2: Nuts16228 Fasteners—Inspection documents

EN

14399 High-Strength Structural Bolting Assemblies For Preloading (series)

14399-1 Part 1: General requirements

14399-2 Part 2: Suitability For preloading

14399-3 Part 3: System HR—Hexagon bolt and nut assemblies

14399-4 Part 4: System HV—Hexagon bolt and nut assemblies

14399-5 Part 5: Plain washers

14399-6 Part 6: Plain chamfered washers

1.4 DEFINITIONS

For the purpose of this Standard, the definitions below apply.

1.4.1 Assembly

The assembly of the matching high-strength bolt, nut and washer supplied together as a set.

1.4.2 Assembly lot

Assemblies supplied together as a set comprising bolts from a single manufacturing lot,

nuts from a single manufacturing lot and washers from a single manufacturing lot.

1.4.3 Concentricity tolerance

Of a bolt, is the allowable deviation of the shank with respect to the pitch diameter of thescrew thread.

1.4.4 Factory production control (FPC)

Comprises operational techniques and all measures necessary to regulate and maintain the

conformity of the product to the requirements of this Standard.

1.4.5 Full tensioning

A method of installing and tensioning a bolt to a minimum level of tension, as defined in

AS 4100 or NZS 3404, as appropriate.

1.4.6 Grip length

Of a bolt, is the thickness of materials which can be clamped.

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1.4.7 HR bolting system

A technical solution that provides ductility in direct tension through ensuring the failure

mode involves tension failure in the bolt shank, which is consistent with the performance

expectations of bolts to this Standard.

NOTE: Refer to EN 14399-3 for more detail.

1.4.8 HV bolting system

A technical solution that provides ductility in direct tension through deformation of the

threads.

NOTE: Refer to EN 14399-4 for more detail.

1.4.9 Inspection documents (for fasteners)

Fastener declaration of compliance F2.1, or test reports F2.2, F3.1 and F3.2, in accordance

with ISO 16228.

1.4.10 k-class

The designation of a bolt assembly which relates the torque applied to the nut to the tension

developed in the bolt.

NOTES:

1 The k-class and designations of K0, K1 and K2 are defined in EN 14399-1.

2 A K0 designation indicates bolt assemblies that do not have a defined torque-tension

relationship. These bolt assemblies cannot be tensioned by torque controlled methods but may

be tensioned by the part turn method or direct tension indicator (DTI) method detailed in

AS 4100 and NZS 3404.

1.4.11 Manufacturer (fastener)

Organization that manufactures fasteners and puts them on the market under its name or

identification mark, or organization that puts fasteners on the market which are marked withits own name or identification mark.

1.4.12 Manufacturing lot

Quantity of fasteners of a single designation including product grade, property class and

size (thread diameter and length), manufactured from bar, wire, rod or flat product from a

single cast, processed through the same or similar steps at the same time or over a

continuous time period, including the same heat treatment and/or coating process, if any.

1.4.13 Manufacturing lot number

Unique alphanumeric code assigned by the fastener manufacturer to a manufacturing lot

enabling its traceability.

1.4.14 May

Indicates the existence of an option.

1.4.15 Nominal length (l )

Of a bolt, is the distance from the bearing surface of the head to the extreme end.

1.4.16 Partial tensioning

A defined degree of tensioning of the bolt assembly that is intermediate between snug tight

and full tensioning.

1.4.17 Preloading

Terminology used to indicate bolt assemblies that are capable of being fully tensioned

(preloaded) to the requirements of the relevant EN Standards.

NOTE: Preloading is referenced in the EN 14399 series.

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1.4.18 Purchaser

Organization or person that buys fasteners, but is not necessarily the user.

NOTE: This may include an importer or distributor.

1.4.19 Shall

Indicates that a statement is mandatory.

1.4.20 Should

Indicates a recommendation.

1.4.21 Supplier

Organization that provides fasteners.

NOTE: The supplier may be the manufacturer, an importer or a distributor.

1.4.22 Symmetry tolerance

1.4.22.1 Of a bolt

The allowable deviation of the across-flats dimension with respect to the shank or the pitch

diameter of the screw thread.

1.4.22.2 Of a nut

The allowable deviation of the across-flats dimension with respect to the pitch diameter of

the screw thread.

1.4.23 Thread length (b)

Of a bolt, is the difference between the nominal length of the bolt and the distance between

the bearing surface of the head and the nearest face of a 6g GO screw ring gauge, screwed

as far as practicable on to the bolt by hand.

1.4.24 Thread run out

1.4.24.1 Bolts with rolled threads

The distance from the top of the extrusion angle to the nearest face of a 6g GO screw ring

gauge, screwed on as far as practicable by hand.

1.4.24.2 Bolts with cut threads

The distance from the last witness of thread to the nearest face of a 6g GO screw ring

gauge, screwed on as far as practicable by hand.

1.4.25 Trace lot number

Unique alphanumeric code assigned by a fastener manufacturer or distributor, whichidentifies the original manufacturing lot number in an unequivocal manner.

1.4.26 Transition diameter (d a)

The diameter of a circle formed at the transition between the fillet radius and the bearing

surface of the head.

1.4.27 Type testing

Testing performed to prove that the product is capable of conforming to the requirements of

this Standard.

1.4.28 Unthreaded shank length (l s)

Of a bolt, is the distance from the bearing surface of the bolt head to the last scratch of

thread, or top of the extrusion angle, whichever is closer to the head.

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1.5 ALTERNATIVE ASSEMBLY TYPE

High-strength structural bolt assemblies for preloading that are manufactured in accordance

with EN 14399-3, System HR, property class 8.8 are the only alternative assembly type that

is deemed to satisfy the requirements of this Standard, and may be used where reference is

made to fasteners conforming to this Standard. NOTE: High-strength bolt assemblies to ‘System HR’ provide ductili ty in direct tension through

ensuring the failure mode involves tension failure in the bolt shank, which is consistent with the

performance expectations of bolts that are manufactured in accordance with this Standard. The

alternative, ‘System HV’, defined in EN 14399-4, provides ductility in direct tension through

failure by thread stripping, a failure mode that may not provide obvious indication that the

assembly has failed. Refer to Appendix A for further information.

1.6 MARKING

1.6.1 Bolts

Except where applicable under Clause 1.6.4, high-strength steel bolts shall be marked with

the following information:

(a) The property class symbol with or without the separating point embossed or indented

on top of the head or indented or rolled into one of the hexagon flats.

(b) Three radial lines approximately 120 degrees apart embossed or indented on top of

the head.

(c) The trade (identification) mark of the manufacturer embossed or indented on top of

the head.

See Figure 1.1(a).

1.6.2 Nuts

Except where applicable under Clause 1.6.4, high-strength steel nuts shall be marked with

the following information:

(a) The property class symbol indented or rolled into a hexagon flat or the bearing surf

ace, or embossed or indented on the external chamfer.

(b) Three circumferential arcs approximately 120 degrees apart embossed or indented on

the non-bearing face, or for double-chamfered nuts, indented on one or both bearing

faces. See Figure 1.1(b).

(c) The trade (identification) mark of the manufacturer embossed or indented on an

external chamfer or indented on the bearing face.

1.6.3 Washers

Except where applicable under Clause 1.6.4, flat round washers for use with high-strength

steel bolts and nuts for structural engineering shall be identified by the provision of three

nibs as shown in Figure 1.1(c).

(c) Washer marking(b) Nut marking(a) Bolt marking

8.8

X Y Z

FIGURE 1.1 IDENTIFICATION MARKING

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1.6.4 Alternative bolt assembly type

For the alternative bolt assembly type, as defined in Clause 1.5, the bolt, nut and washer

shall be identified as shown in Figure 1.2.

(c) Washer marking(b) Nut marking(a) Bolt marking

XYZXYZ

8 8 HR8.8 HR

XYZXYZ

8 HR8 HR

XYZXYZ

HH

NOTE: The identification marking shown in Figure 1.2 is consistent with that required in EN 14399-3.

FIGURE 1.2 IDENTIFICATION MARKING FOR ALTERNATIVE ASSEMBLY TYPE

1.7 DESIGNATION

1.7.1 Bolts

Except where applicable under Clause 1.7.4, the designation of high-strength steel bolts for

structural engineering shall be composed of the following:

(a) General product description.

(b) The number of this Australian/New Zealand Standard, i.e. AS/NZS 1252.

(c) The letter ‘M’ indicating that the product has a metric coarse pitch series thread

followed by the nominal size (thread diameter), in millimetres.

(d) The nominal length, in millimetres.

(e) The property class symbol.

(f) The coating, where applicable in accordance with the appropriate Standard.

(g) Any other features.

Example:

Hot-dip galvanized high-strength steel bolts, 20 mm diameter and 100 mm long, are

designated—

High-strength steel bolts for structural engineering to AS/NZS 1252—M20 × 100— 8.8 (hot dip galvanized to AS 1214).

1.7.2 Nuts

Except where applicable under Clause 1.7.4, the designation of high-strength steel nuts for

structural engineering shall be composed of the following:



(c) The letter ‘M’ indicating that the product has a metric coarse pitch series thread


(d) The property class symbol.

(e) The coating, where applicable, in accordance with the appropriate Standard.

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(f) Any other features.

Example:

Uncoated high-strength steel nuts with 20 mm threads are designated—

High-strength steel nuts for structural engineering to AS/NZS 1252—M20—8.1.7.3 Washers

Except where applicable under Clause 1.7.4, the designation of hardened and tempered

washers for structural bolting shall be composed of the following:



(c) The nominal size (nominal bolt diameter), in millimetres.

(d) The coating, where applicable, in accordance with the appropriate Standard.

(e) Any other features.

Example:

20 mm hot-dip galvanized hardened and tempered steel washers for structural engineering

are designated—

Steel washers for structural bolting to AS/NZS 1252—20 (hot-dip galvanized to

AS/NZS 4680).

NOTE: Bolts, nuts and washers should be supplied as assemblies.

1.7.4 Alternative bolt assembly types

For alternative bolt assembly types, as defined in Clause 1.5, the designation of the bolt, nut

and washer shall be as required in the applicable product standard.

NOTE: This should be as follows:

(a) For bolts:

(i) General product description.

(ii) The number of the relevant Standard, i.e. EN 14399-3.

(iii) The letter ‘M’ indicating that the product has a metric coarse pitch series thread


(iv) The nominal length, in millimetres.

(v) The property class symbol and HR designation.

(vi) The surface finish, where applicable, in accordance with the appropriate Standard.

(vii) Any other features.(b) For nuts:



(iii) The letter ‘M’ indicating that the product has a metric coarse pitch series thread


(iv) The property class symbol and HR designation.

(v) The surface finish, where applicable, in accordance with the appropriate Standard.

(vi) Any other features.

(c) For washers:



(iii) The nominal size (thread diameter), in millimetres.

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(iv) The surface finish, where applicable, in accordance with the appropriate Standard.

(v) Any other features.

Example:

Designation of a bolt/nut assembly and washer for high-strength structural bolting for preloading,

system HR, consisting of a hexagon head bolt with thread M16, nominal length of 80 mm andproperty class 8.8; a hexagon nut with thread M16 and property class 8; and a hardened and

tempered plain washer for preloading of nominal size to suit M16 bolt, uncoated—

Bolt/nut assembly EN 14399-3—M16 × 80–8.8/8-HR

Washer EN 14399-5—16

1.8 PRODUCT REQUIREMENTS

1.8.1 General

Means for demonstrating compliance with this Standard are specified in Appendix B.

1.8.2 Dimensions, tolerances, materials and mechanical properties

Bolts, nuts and washers manufactured to this Standard shall conform to the requirements in

Sections 2, 3 and 4 of this Standard, respectively.

Components of alternative bolt assemblies, as defined in Clause 1.5, shall conform to the

requirements of the applicable product standard cited in Clause 1.5.

1.8.3 Galvanized nut threading process

Hot-dip galvanized nuts shall be galvanized before they are threaded. Nuts shall not be

re-threaded.

1.8.4 Finish and coating

Finish and coating shall be as specified in the relevant part of this Standard.

Coatings of all components of an assembly shall be compatible and shall have similar

corrosion resistance.

Hot dip galvanizing of each component shall be under the control of the manufacturer of the

assemblies.

1.8.5 Functional characteristics of the assembly

The performance of the structural bolt assembly shall conform to the requirements given in

Section 5 of this Standard.

Alternative bolt assemblies, as defined in Clause 1.5, shall conform to the requirements of

the applicable product standard cited in Clause 1.5.

1.8.6 Delivery conditions

Bolt assemblies shall be supplied to the purchaser either in the original unopened single

sealed container or alternatively in the separate sealed containers of the manufacturer of the

assemblies with identification in accordance with Section 6.

High-strength bolts, nuts and washers shall be supplied as a complete assembly from the

one manufacturer.

Different bolt assembly types shall not be supplied mixed in the same box.

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S E C T I O N 2 H I G H - S T R E N G T H S T E E L B O L T S

2.1 METHOD OF MANUFACTURE

High-strength steel bolts shall be—

(a) hot or cold forged with or without secondary machining; or

(b) machined from bar stock.

2.2 SHAPE, DIMENSIONS AND FINISH

2.2.1 Head

The heads of high-strength steel bolts shall be in accordance with Figure 2.1 and Table 2.1.

The dimensions given in Table 2.1 apply before hot-dip galvanizing.

2.2.2 LengthThe length of high-strength steel bolts shall be as given in Table 2.2.

2.2.3 Ends

The ends of high-strength steel bolts shall be finished with a 45-degree chamfer to a depth

slightly exceeding the depth of thread (see Figure 2.1).

2.2.4 Screw threads

2.2.4.1 General

The form of thread, diameters and associated pitches of high-strength steel bolts shall be the

ISO coarse pitch series in accordance with AS 1275.

Screw threads shall be formed by thread rolling or thread cutting.

2.2.4.2 Tolerances

The screw threads shall be made to tolerance class 6g in accordance with AS 1275.

Where bolts are to be hot-dip galvanized, the 6g tolerance class applies before hot-dip

galvanizing.

2.2.5 Thread length (b)

The nominal thread lengths for high-strength steel bolts shall be as given in Table 2.3.

The tolerances on the thread length shall be such that the grip lengths ( l g) and unthreaded

shank lengths (l s) given in Table 2.2 are maintained.

The grip length (l g) shall be determined as the distance between the bearing surface of the

head and the nearest face of a 6g GO screw ring gauge, screwed as far as practicable on to

the bolt by hand. This dimension applies before hot-dip galvanizing.

2.2.6 Squareness, concentricity and symmetry

2.2.6.1 Squareness of bearing face

When determined as shown in Figure 2.2(a), the bearing face of the head shall be square,

within the values given in Table 2.1, to the shank. The values are based on an angle of two

degrees.

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2.2.6.2 Concentricity of shank to screw thread

When determined as shown in Figure 2.2(b), the shank for a distance of 1.5 diameters from

the nearest face of a 6g GO screw ring gauge screwed as far as practicable on to the thread

by hand shall be concentric, within the values given in Table 2.1, to the pitch diameter of

the screw thread.2.2.6.3 Symmetry of head to shank

When determined as shown in Figure 2.2(c), the head shall be symmetric, within the values

given in Table 2.1, to the shank.

2.2.7 Chamfering and washer facing

High-strength steel bolts shall have heads with a chamfer of 15 to 30 degrees on their upper

faces. The diameter of the circle formed by this chamfer shall be not less than 90 percent of

the minimum width across-flats of the bolts.

Bolts shall have a washer face on the underside of the head (see Figure 2.1). The diameter

and depth of washer faces shall be as given in Table 2.1.2.2.8 Shank

2.2.8.1 Diameter

The diameter (d s) of the shank of high-strength steel bolts shall be as given in Table 2.1.

2.2.8.2 Straightness

High-strength steel bolts shall be straight within the tolerance shown in in Figure 2.3.

2.2.9 Underhead fillet

The fillet junction of the head and shank shall be a smooth concave curve lying within an

envelope defined by the minimum radius under the head (r) and a maximum profile defined

by a tangent to a radius equal to the minimum value of r blending to the maximum

transition diameter on the underside of the head and the fillet length ( l f ) on the shank as

shown in Figure 2.1. The minimum values of r and the maximum values of l f are given in

Table 2.1.

2.2.10 Finish

2.2.10.1 General

High-strength steel bolts shall be cleanly finished, sound, and free from defects detrimental

to their end use. The surface discontinuities on high-strength steel bolts shall be not greater

than the limits given in ISO 6157-1.

2.2.10.2 Surface roughness

All surfaces of high-strength steel bolts, except screw threads, may be in the as-forged or

machined condition. Screw threads shall be machined or have a surface quality equivalent

to machining.

2.2.10.3 Surface finish and coating

High-strength steel bolts may be supplied with either decorative or corrosion-resistant

coatings. Coatings of all components of an assembly shall be compatible and shall have

similar corrosion resistance.

High-strength hot-dip galvanized steel bolts shall be supplied in accordance with AS 1214

unless otherwise specified.

Electroplated high-strength steel bolts shall be supplied in accordance with either AS 1897

or ISO 4042 unless otherwise specified. Electroplated high-strength steel bolts shall not be

coated in cadmium or cadmium alloy.

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Uncoated bolts shall be in the dull black as-heat-treated condition.

NOTE: Where the purchaser requires coated products, coatings should be specified to the relevant

coating specification, e.g. AS 1897, and indicated in the enquiry or order.

2.3 MATERIALS AND MECHANICAL PROPERTIES

The materials and mechanical properties of high-strength steel bolts shall be as given in

AS 4291.1 for property class 8.8.

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1 0 3 3 4 3 A S NZ S 1 2 5 2 .1 P u b l i c

C omm en t . d o c - 0 9 / 0 3 / 2 0 1 6 9 : 2 9 : 1 9

TABLE 2.1

GENERAL DIMENSIONS OF HIGH-STRENGTH STEEL BOLTS

Thread

(see

Note 1)

Pitch

Shank

diameter

Width

across flats

Width

across corners

Washer face

dia.

Depth of

washer face

Fillet details

Height of

headTran-

sition

dia.

Radius

under

head

Fillet

length

(d s) ( s) (e) (d w) (c) (d a) (r ) (l f ) (k )

(p) Max. Min. Max. Min. Max. Min. Max. Min. Max. Min. (max.) (min.) (max.) Max. Min

M12 1.75 12.70 11.30 21 20.16 24.25 22.78 19.2 0.8 0.4 14.70 0.6 3.0 7.95 7.0

M16 2.0 16.70 15.30 27 26.16 31.2 29.56 Actual 24.9 0.8 0.4 18.70 0.6 3.0 10.75 9.2

M20 2 .5 20.84 19 .16 32 31 .00 36.9 35.03 s ize 29.5 0 .8 0.4 23 .24 0.8 4.0 13.90 12 .1

(M22) 2 .5 22.84 21 .16 36 35 .00 41.6 39 .55 across 33.3 0 .8 0.4 25 .24 0.8 4.5 14.90 13 .1

M24 3.0 24.84 23.16 41 40.00 47.3 45.20 f la ts 38.0 0.8 0.4 27.64 1.0 5.0 15.90 14.

(M27) 3 .0 27.84 26 .16 46 45 .00 53.1 50 .85 42.8 0 .8 0.4 31 .24 1 .2 6.0 17.90 16 .1

M30 3.5 30.84 29.16 50 49.00 57.7 55.37 46.5 0.8 0.4 34.24 1.2 6.0 19.75 17.6

M36 4.0 37.00 35.00 60 58.80 69.3 66.44 55.9 0.8 0.4 41.00 1.5 7.5 23.55 21.4

NOTES:

1

Threads in parentheses are non-preferred.

2

For hot-dip galvanized bolts, the dimensions apply before galvanizing.

3

Values equal to FIM (full indicator movement).

Licensed to Mr Andrew Brown on 17 March 2016. Personal use licence only. Storage, distribution or use on netwo

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1 0 3 3 4 3 A S NZ S 1 2 5 2 .1 P u b l i c

C omm en t . d o c - 0 9 / 0 3 / 2 0 1 6 9 : 2 9 : 1 9

TABLE 2.2

LENGTH OF HIGH-STRENGTH STEEL BOLTS

Overall length

Thread

M12 M16 M20 (M22) M24 (M27)

Unthreaded shank lengths (l s) and grip lengths (l g)

(l ) l s l g l s l g l s l g l s l g l s l g l s l g

Nom. Min. Max. (min. ) (max.) (min. ) (max. ) (min.) (max. ) (min. ) (max.) (min.) (max. ) (min.) (max.)

35 33.75 36.25 6 11 — — — — — — — — — —

40 38.75 41.25 6 11 8 14 — — — — — — — —

45 43.75 46.25 6 15 8 14 10 17.5 — — — — — —

50 48.75 51.25 11 20 8 14 10 17.5 11 18.5 — — — —

55 53.5 56.5 16 25 11 17 10 17.5 11 18.5 12 21 — —

60 58.5 61.5 21 30 16 22 10 17.5 11 18.5 12 21 — —

65 63.5 66.5 26 35 21 27 11.5 19 11 18.5 12 21 13.5 22.5

70 68.5 71.5 31 40 26 32 16.5 24 12.5 20 12 21 13.5 22.5

75 73.5 76.5 36 45 31 37 21.5 29 17.5 25 12 21 13.5 22.5

80 78.5 81.5 41 50 36 42 26.5 34 22.5 30 17 26 13.5 22.5

85 83.25 86.75 46 55 41 47 31.5 39 27.5 35 22 31 16 25

90 88.25 91.75 51 60 46 52 36.5 44 32.5 40 27 36 21 30

95 93.25 96.75 56 65 51 57 41.5 49 37.5 45 32 41 26 35

100 98.25 101.75 61 70 56 62 46.5 54 42.5 50 37 46 31 40

110 108.25 111.75 — — 66 72 56.5 64 52.5 60 47 56 41 50

120 118.25 121.75 — — 76 82 66.5 74 62.5 70 57 66 51 60

130 128 132 — — 80 86 70.5 78 66.5 74 61 70 55 64

140 138 142 — — 90 96 80.5 88 76.5 84 71 80 65 74

150 148 152 — — 100 106 90.5 98 86.5 94 81 90 75 84


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1 0 3 3 4 3 A S NZ S 1 2 5 2 .1 P u b l i c

C omm en t . d o c - 0 9 / 0 3 / 2 0 1 6 9 : 2 9 : 1 9

Overall length

Thread

M12 M16 M20 (M22) M24 (M27)

Unthreaded shank lengths (l s) and grip lengths (l g)

(l ) l s l g l s l g l s l g l s l g l s l g l s l g

Nom. Min. Max. (min. ) (max.) (min. ) (max. ) (min.) (max. ) (min. ) (max.) (min.) (max. ) (min.) (max.)

160 156 164 — — — — — — — — 91 100 85 94

170 166 174 — — — — — — — — 101 110 95 104

180 176 184 — — — — — — — — 111 120 105 114

190 186 194 — — — — — — — — 121 130 115 124

200 196 204 — — — — — — — — 131 140 125 134

220 216 224 — — — — — — — — 138 147 132 141

240 236 244 — — — — — — — — 158 167 152 161

NOTES:

1 Threads in parentheses are non-preferred.

2 For bolts below the dotted line—

l g = l b; and

l s = l g 3 p

For bolts above the dotted line—

l s = 0.5d ; and

l g = l s + 3 p

where

l g = maximum grip length, in millimetres

l = nominal length of bolt, in millimetres (see Table 2.2)

b = nominal thread length, in millimetres

l s = minimum unthreaded shank length, in millimetres

p = pitch of thread, in millimetres

d = nominal diameter of thread, in millimetres

3 Bolts above the dotted line have shortened thread lengths.

4 The difference between l s (min.) and l g (max.) shall be not less than 1.5p.

5 Inclusion of diameter/length combinations in Table 2.2 does not necessarily mean that these are stock items. The

manufacturer’s listings for stock availability.

TABLE 2.2 (continued )


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TABLE 2.3

NOMINAL THREAD LENGTHS

millimetres

Nominal bolt

lengthBasis for

thread

length*

Nominal length of thread (b)

(l ) M12 M16 M20 (M22) M24 (M27) M30 M36

>125

>200

≤125

≤200

2d + 6

2d + 12

2d + 25

30

—

—

38

44

—

46

52

65

50

56

69

54

60

73

60

66

79

66

72

85

78

84

97

* d = nominal thread diameter, in millimetres

NOTES:

1


2

The thread lengths specified in Table 2.3 are not applicable to bolts above the dotted line in Table 2.2.

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s

e

k ℓ

ℓg

b

ℓs

da

ds

ds

Point shall

be chamfered

See detai l (b)

15° to 30°

da

dw

r r

0.1 mm Reference datum for dw

ℓf

k

c

Maximum underhead f i l let

(a) Hexagon bolt

(b) Enlarged detai l of f i l let

FIGURE 2.1 HIGH-STRENGTH STEEL BOLTS

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t Ø t

Ø t

Ø 0.8 sd sds d

d * 1.5d d

d *

d(3p max.)

d

ds

* See (d), Posit ion of datum

* See (d), Posit ion of datum

(a) Squareness of bearing face

(c) Head symmetry (d) Pos it ion of datum

(b) Concentr ic i ty of shank

NO TE: The datum may be the

length of the 6 g GO screw r i ng

gauge.

NO TE: The datum shal l not be the

par t ial ly th rea ded shank. I f necassar ythe datum should be displaced at a

suff icient distance (3 p max.) f rom the

head of the bolt to avoid thread ru nout.

FIGURE 2.2 SQUARENESS, CONCENTRICITY AND SYMMETRY OF

HIGH-STRENGTH STEEL BOLTS

d

Ø t

2d ℓ´*

t = 2(0.0025 ℓ´ + 0.05)

* Straightness is applicable only for ℓ´

DIMENSIONS IN MILLIMETRES

FIGURE 2.3 TOLERANCE ON STRAIGHTNESS OF HIGH-STRENGTH

STEEL BOLTS

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S E C T I O N 3 H I G H - S T R E N G T H S T E E L N U T S


High-strength steel nuts shall be—

(a)

hot or cold formed with or without subsequent machining; or

(b) machined from bar stock.


3.2.1 General

The shape of nuts shall be in accordance with Figure 3.1.

The thread form, diameters and associated pitches of nuts shall be those of the ISO coarse

pitch series in accordance with AS 1275.

3.2.2 Tolerances

The screw threads of uncoated nuts shall be made to tolerance class 6H in accordance with

AS 1275.

For hot-dip galvanized nuts, the dimensions in Figure 3.1 apply before hot-dip galvanizing.

Hot-dip galvanized nuts shall be galvanized before they are threaded. Re-threading shall not

be permitted. Hot-dip galvanized nuts shall be tapped oversize to tolerance class 6AZ in

accordance with AS 1214 after galvanizing.

For electroplated nuts, the dimensions in Figure 3.1 apply before plating. Threads on

electroplated nuts shall meet tolerance class 6H in accordance with AS 1897 (ISO 4042)

after electroplating.

3.2.3 Squareness and symmetry

3.2.3.1 Squareness of thread to bearing face(s)

When determined as shown in Figure 3.2(a), the bearing face(s) of the nut shall be square,

within the values given in Figure 3.1, to the pitch diameter of the screw thread.

3.2.3.2 Symmetry of hexagon

When determined as shown in Figure 3.2(b), the hexagon shall be symmetrical, within the

values given in Figure 3.1, to the pitch diameter of the screw thread.

3.2.4 Chamfering, washer facing and countersinking

3.2.4.1 Chamfering and washer facing

Nuts shall have a chamfer of 15 to 30 degrees on both faces, or a chamfer of 15 to

30 degrees on their upper face and a washer face on the bearing surface. The bearing faces

shall be smooth and flat. The minimum washer face or chamfer diameter (d w) shall be not

less than that given in Figure 3.1.

3.2.4.2 Countersinking

Nuts shall be radiused or countersunk on the bearing face or faces. The maximum

countersink diameter (d a ) shall be not greater than the value given in Figure 3.1.

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3.2.5 Finish

3.2.5.1 General

High-strength steel nuts shall be cleanly finished, sound and free from defects detrimental

to their end use. The surface discontinuities shall be not greater than the limits given in

ISO 6157-2.3.2.5.2 Surface roughness

All surfaces of high-strength steel nuts, except screw threads, may be in the as-forged or

machined condition. Screw threads shall be machined or have a surface quality equivalent

to machining.

3.2.5.3 Surface finish and coating

High-strength steel nuts may be supplied with either decorative or corrosion resistant

coatings. Coatings of all components of an assembly shall be compatible and shall have

similar corrosion resistance.

Hot-dip galvanized nuts shall be supplied in accordance with AS 1214 unless otherwisespecified.

Electroplated nuts shall be supplied in accordance with AS 1897 (ISO 4042) unless

otherwise specified. Electroplated nuts shall not be coated in cadmium or cadmium alloy.

Uncoated nuts shall be in the dull black as-heat-treated condition.

NOTES:

1 The assembly test in Appendix D is a suitable test for the effectiveness of the lubricant

coating.

2 Coatings should be specified to the relevant coating specification, e.g. AS 1897, and indicated

in the enquiry or order.

3.2.5.4 Lubrication

All coated nuts shall be provided with an additional lubricant coating to prevent seizure on

assembly. The coating shall be clean and dry to the touch.

All uncoated nuts shall be provided with an additional lubricant coating to prevent seizure

on assembly.

3.3 MATERIAL AND MECHANICAL PROPERTIES

The material of high-strength steel nuts shall be as given in AS/NZS 4291.2 for property

class 8. The mechanical properties shall be as given in Tables 3.1 and 3.2 of this Standard.

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1 0 3 3 4 3 A S NZ S 1 2 5 2 .1 P u b l i c

C omm en t . d o c - 0 9 / 0 3 / 2 0 1 6 9 : 2 9 : 1 9

s m m

c

e dw dw

15° to 30°15° to 30°

(a) Double-chamfered nut (b) Washer-faced nut

Thread*

Pitch

of

thread

Width across

flat

Width across

cornersNut height Squareness

tolerance†

Symmetry

tolerance†

Washer-face or

chamfer dia.

(s) (e) (m) (d w)

(p) Max. Min. Max. Min. Max. Min. (Max.) (Min.) Max. Min.

M12 1.75 21.0 20.16 24.25 22.78 13.1 12.0 0.22 1.04 19.20

M16 2.0 27.0 26.16 31.2 29.56 17.1 16.4 0.76 1.04 Actual 24.90

M20 2.5 32.0 31.00 36.9 35.03 21.3 20.0 0.90 1.24 size 29.50

(M22) 2.5 36.0 35.00 41.6 39.55 23.6 22.3 1.00 1.24 cross 33.30

M24 3.0 41.0 40.00 47.3 45.20 24.2 22.9 1.04 1.24 flats 38.00

(M27) 3.0 46.0 45.00 53.1 50.85 27.6 26.3 1.28 1.24 42.80

M30 3.5 50.0 49.00 57.7 55.37 30.7 29.1 1.40 1.24 46.50

M36 4.0 60.0 58.80 69.3 66.44 36.6 35.0 1.68 1.48 55.90

*

†


Values equal to FIM (full indicator movement).

FIGURE 3.1 SHAPE AND DIMENSIONS OF HIGH-STRENGTH STEEL NUT


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Ø 0.8s d d

t Ø t

s

(a) Squareness to lerance (b) Symmetry tolerance

FIGURE 3.2 SQUARENESS AND SYMMETRY OF HIGH-STRENGTH

STEEL NUTS

TABLE 3.1

MECHANICAL PROPERTIES OF HIGH-STRENGTH STEEL NUTS

Nut finish

Proof

stress

Hardness

Vickers HV Rockwell HRC HRB

MPa Max. Min. Max. Min.

Hot-dip galvanized 1165 353 260 36 24 —

Other than hot-dip

galvanized1075

353 188 36 — 89

NOTE: The coat ing sha ll be removed before hardness testing.

TABLE 3.2

PROOF LOADS FOR HIGH-STRENGTH STEEL NUTS

Thread

Tensile stress area of

threaded test mandrel

( As)

Proof load

kN

mm2 Hot-dip

galvanized

Other than hot-dip

galvanized

M12

M16

M20

84.3

157

245

98.2

182.9

285.4

90.6

168.9

263.4

M22

M24

M27

303

353

459

353.0

411.2

534.7

325.7

379.5

493.4

M30

M36

561

817

653.6

951.8

603.1

878.3

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S E C T I O N 4 F L A T R O U N D W A S H E R S


Washers shall be manufactured from steel produced by a basic oxygen or an electric arc

process.


4.2.1 Shape and dimensions

The shape and dimensions of washers for high-strength structural bolting shall be in

accordance with Figure 4.1. For coated washers, the dimensions apply before coating.

NOTE: Dimensions of square taper washers are given in Appendix E.

4.2.2 Flatness

When a straight edge is placed along a line passing through the centre of the hole, thedeparture from flatness determined by inserting thickness gauges at a point midway

between the edge of the hole and the edge of the washer shall be not greater than 0.25 mm.

4.2.3 Finish

4.2.3.1 General

Washers for high-strength steel bolts shall be cleanly finished, sound and free from defects

detrimental to the end use.

4.2.3.2 Surface roughness

All surfaces of washers for high-strength structural bolting may be in the as-rolled or

machined condition.4.2.3.3 Surface finish and coating

Washers may be supplied with either decorative or corrosion-resistant coatings. Coatings of

all components of an assembly shall be compatible and shall have similar corrosion

resistance.

Hot-dip galvanized washers shall be supplied in accordance with AS 1214 or AS/NZS 4680

unless otherwise specified.

Electroplated washers shall be supplied in accordance with AS 1897 (ISO 4042) unless

otherwise specified. Electroplated washers shall not be coated with cadmium or cadmium

alloy.

Uncoated washers shall be in the dull black as-heat-treated condition.

4.3 MATERIAL AND MECHANICAL PROPERTIES

All washers shall be hardened and tempered and the hardness shall be 345–455 HV (35–

45 HRC).

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DRAFTING NOTE: The hardness of structural washers in accordance with AS 1252-1983

was 35HRC (345HV)–45HRC (455HV). This was since changed to 26HRC (275HV) –

45HRC (455HV) in AS 1252-1996.

This change has made certain concerns when used in combination with the Load Indicating

Washers (LIW). As the maximum hardness for LIW in accordance with I.S. EN 14399-9 is380HV or 38HRC, a lower hardness on the structural washer would indent the washer

instead of deforming the LIW making LIW not reliable. In order to address this issue (at

least partially), the hardness range for structural washers in the new revision of AS 1252.1

is set at 35HRC (345HV)–45HRC (455HV) which is same as that of the AS1252-1983.

There is a concern by the HDG applicators that achieving a minimum hardness of 35HRC

(345HV) is not practical due to 550C bath temperature used in some HDG processes.

HDG structural washers having hardness greater than 35HRC are currently and were

previously available in the Australian Market while some currently available HDG

structural washers are below this hardness.

We seek your comments on this matter. NOTES:

1 These hardness requirements are for all coating types.

2 Where direct tension indicators (DTI) are used, if the minimum hardness is below 35 HRC,

the DTI indentation may indent the steel and provide erroneous results.

d2

1

d1

h

millimetres

Nominal

diameter of

bolt

Inside diameter Outside diameter Thickness

(d 1) (d 2) (h)

(d )* Max. Min. Max. Min. Max. Min.

12

16

20

14.43

18.43

22.52

14.0

18.0

22.0

26.0

34.0

42.0

24.4

32.4

40.4

3.3

4.6

4.6

2.7

3.1

3.1

(22)

24

(27)

24.52

26.52

30.52

24.0

26.0

30.0

44.0

50.0

56.0

42.4

48.4

54.1

4.6

4.6

4.6

3.4

3.4

3.4

30

36

33.62

39.62

33.0

39.0

60.0

72.0

58.1

70.1

4.6

4.6

3.4

3.4

* Values in parentheses are non-preferred.

FIGURE 4.1 SHAPE AND DIMENSIONS OF FLAT ROUND WASHERS FOR

HIGH-STRENGTH STRUCTURAL BOLTING

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S E C T I O N 5 B O L T A S S E M B L I E S

5.1 GENERAL

A bolt assembly shall comprise a bolt meeting the requirements of Section 2, a nut meeting

the requirements of Section 3 and a washer meeting the requirements of Section 4.

Bolt assemblies shall be supplied containing components only from the same manufacturing

lot.

5.2 FUNCTIONAL CHARACTERISTICS OF THE BOLT ASSEMBLY

5.2.1 General

The functional characteristics of the bolt assembly shall meet the requirements defined in

Clauses 5.2.2, 5.2.3 and 5.2.4 when tested in accordance with the basic assembly test or

extended assembly test, as appropriate, detailed in Appendix D.

5.2.2 Minimum bolt tension force

The minimum tension force developed in the bolt during the basic assembly test shall be in

accordance with Table 5.1.

TABLE 5.1

MINIMUM BOLT TENSION

FOR ASSEMBLY TEST

Nominal diameter

of bolt

Minimum bolt tension

kN

M12

M16

M20

M22

M24

M27

M30

M36

63

117

183

227

264

343

419

610

NOTE: The minimum bol t tensions given in Table 5.1

are approximately equivalent to 0.9 × (minimum

ultimate tensile load) as specified in AS 4291.1.

5.2.3 Minimum nut rotation

The minimum nut rotation shall be assessed using the basic assembly test.

The minimum nut rotation from when the tension of the bolt is equal to 0.7 × (minimum

ultimate tensile load) condition achieved during the basic assembly test without fracture of

the bolt or stripping of the bolt or nut thread or reaching the bolt tension of 0.7 × (minimum

ultimate tensile load) again shall be as given in Table 5.2.

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TABLE 5.2

NUT ROTATION REQUIREMENTS

Bolt length

(nominal)

Nut rotation (minimum)

after snug tightdegrees

≤3d 300

>3d ≤7d 360

>7d ≤11d 420

5.2.4 Torque-tension relationship

Where the bolt installation procedure relies on a known and documented relationship

between the torque applied to the nut (or bolt) and the tension developed in the bolt

assembly, the relationship shall be defined by—

M r,i = k m d F p,C where

M r,i = torque required to develop minimum bolt tension F p,C

k m = k m for k-class K1 or K2 as appropriate (refer to Appendix D)

d = nominal diameter of the bolt

F p,C = minimum bolt tension (preload) defined in the relevant Standard

The extended assembly test detailed in Appendix D shall be used to establish the relevant

values of k m for k-class K1 or K2 as appropriate.

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S E C T I O N 6 I D E N T I F I C A T I O N ,

C E R T I F I C A T I O N A N D T E S T I N G

6.1 GENERAL

6.1.1 Availability of test certificates

A test certificate shall be available to the purchaser for all products manufactured to this

Standard for each manufacturing lot produced.

NOTE: The term ‘certificate’ is in common use, however, for fastener inspection documents the

terminology used by ISO is ‘test report’.

6.1.2 Transmission of test certificates

An original or a copy of the inspection documents provided by the manufacturer or its

approved representative, without any alteration, shall be provided. This documentation shall

be accompanied by suitable means of identification of the product, in order to ensure the

traceability between the manufacturing lot and the corresponding test certificate.

Copying of the original documentation is permitted, provided that—

(a) traceability of product is maintained; and

(b) the original document is available on request.

When producing copies, the information on the original delivered quantity may be replaced

by the actual delivered partial quantity.

6.2 IDENTIFICATION

Each package or box of bolt assembly components shall be from the same manufacturing

lot. Each package or box shall be identified with the following:

(a)

Product designation (see Clause 1.7).

(b)

The name and address of the manufacturer or supplier.

(c)

Batch and heat identification number for the manufacturing lots from which the bolt,

nut and washer were taken.

(d) The k-class (K0, K1 or K2) with the corresponding values required by the applicable

Standard. Where not shown, K0 shall be assumed. See Clause 5.2.4.

(e) A manufacturing lot number. A trace lot number may replace or complement the

manufacturing lot number.

6.3 TESTING AND TEST REPORTS

6.3.1 General

Testing shall be performed by a laboratory accredited by a signatory to the International

Laboratory Accreditation Corporation (ILAC) through their Mutual Recognition Agreement

(MRA) for the specific tests set out in this Standard. The appropriate logo or further details

of the ILAC (MRA) signatory shall be noted on the test certificate.

NOTE: In Australia, ILAC (MRA) bodies include the National Association of Testing Authorit ies

(NATA); in New Zealand, they include International Accreditation New Zealand (IANZ).

Additional tests not considered in this Standard may also be reported, as agreed between the

purchaser and supplier.

NOTE: To comply with ILAC requirements, any additional tests will either need to have

accreditation or, if not accredited, be reported such that it is clear the testing is not accredited. A

separate report may be necessary.

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6.3.2 Minimum requirements for test reports

All test reports shall be in English alphanumeric characters, issued by the manufacturer or

supplier as appropriate, and have the following:

(a) The name and address of the fastener manufacturer or supplier who establishes the

inspection document.(b)

The report number (unique identification allocated by the fastener manufacturer or

supplier for its own traceability to test/inspection results).

(c) Indication of the quality system(s) operated by the fastener manufacturer or supplier.

(d) Product designation (see Clause 1.7).

(e) Batch, heat and manufacturing lot number (or trace lot number) for each

manufacturing lot.

(f)

Size of the manufacturing lot.

(g)

The fastener marking (see Clause 1.6).

(h)

The manufacturer identification (trade) mark of the labelling, if any, unless identical

to the fastener marking.

(i) Identification and address of the test laboratory and accreditation details of the test

laboratory and the test identification number(s) for the measured values [refer to

Item (j)] date of issue, page number and total number of pages on each page.

(j) Measured values in comparison to specified values for each of the properties required

to be reported in this Standard.

The test report shall be accompanied by a declaration of conformity from the manufacturer

that the products supplied comply with the requirements of this Standard and Items (a) to (j)

above. This shall be validated by the manufacturer’s or supplier’s authorized representative,

including their name, signature and position.

NOTE: The above requirements are consistent with a Type F3.1 test report according to

ISO 16228. A Type F3.1 test report is acceptable for alternative bolt assembly types (see

Clause 1.7.4).

6.4 TESTING OF DIMENSIONAL REQUIREMENTS

6.4.1 Bolts

The critical dimensions to be tested and tolerances for bolts are provided in Table 6.1.

Standard gauges or measuring equipment of the required accuracy shall be used.

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TABLE 6.1

DIMENSIONAL TESTS FOR BOLTS

Critical dimension1 Accuracy (mm) Method

Width across flats (s) ≤0.05 Measurement

Width across corners (e) ≤0.05 Measurement

Head height (k ) ≤0.05 Measurement

Shank diameter (d s) ≤0.05 Measurement

Nominal length (l ) ≤0.1 Measurement

Shank length (l s) ≤0.1 Measurement

Grip length (b) ≤0.1 Measurement

Thread dimensions — Gauge

Underhead radius (r) — Gauge

1 Symbols are defined in Figure 2.1.

6.4.2 Nuts

The critical dimensions to be tested and tolerances for nuts are provided in Table 6.2.


TABLE 6.2

DIMENSIONAL TESTS FOR NUTS


Width across flats (s) ≤0.05 Measurement

Width across corners (e) ≤0.05 Measurement

Nut height (m) ≤0.05 Measurement

Thread dimensions — Gauge


6.4.3 Washers

The critical dimensions to be tested and tolerances for washers are provided in Table 6.3.


TABLE 6.3

DIMENSIONAL TESTS FOR WASHERS


Hole diameter (d 1) ≤0.1 Measurement/gauge

Outer diameter (d 2) ≤0.1 Measurement

Thickness (h) ≤0.05 Measurement


6.5 TESTING OF MECHANICAL CHARACTERISTICS

6.5.1 Bolts

The mechanical properties of bolts shall be tested in accordance with Table 6.4.

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TABLE 6.4

TESTS FOR MECHANICAL PROPERTIES OF BOLTS

Mechanical property Test

Reference Standard

for the test procedureAS 4291.1:2015

Test assessment

criteria(Note 1)

AS 4291.1:2015

Minimum tensile strength

Rm, MPa

Tensile test under

wedge loading(Note 2)

Clause 9.1 Clause 9.1.6.1.2

Tensile test Clause 9.2 Clause 9.2.6.2

Stress at 0.2% non-

proportional elongation

R0.2 , MPa


Stress under proof load S p,

MPa

Proof load test Clause 9.6 Clause 9.6.6

Percentage elongation after

fracture for machined testpieces A, %


Percentage reduction of

area after fracture for

machined test pieces Z , %


Hardness Hardness test Clause 9.9 Clause 9.9.5

Height of non-carburization

thread zone E , mm

Decarburization test Clause 9.10 Clause 9.10.3.4

Reduction of hardness after

retempering, HV

Retempering test Clause 9.12 Clause 9.12.4

Impact strength K V, J Impact test Clause 9.14 Clause 9.14.6

Surface integrity Surface discontinuity

inspection

Clause 9.15 Clause 9.15

NOTES:

1 The test assessment criteria column specifies the relevant Clause in AS 4291.1.

2 Applicable to bolts of length ≥2.5d .

6.5.2 Nuts

The mechanical characteristics of nuts shall be tested in accordance with Table 6.5.

TABLE 6.5

TESTS FOR MECHANICAL CHARACTERISTICS OF NUTS

Mechanical

characteristicTest

Reference Standard for

the test procedure

Test assessment criteria

Hardness Hardness test AS/NZS 4291.2 Table 3.1 of this Standard

Stress under proof load Proof load test AS/NZS 4291.2 Table 3.2 of this Standard

6.5.3 Washers

The mechanical characteristics of washers shall be tested in accordance with Table 6.6.

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TABLE 6.6

TESTS FOR MECHANICAL CHARACTERISTICS

OF WASHERS

Mechanical

characteristic

TestReference Standard for

the test procedure

Test assessment criteria

Hardness Hardness testAS 1817.1 for Vickers method

AS 1815.1 for Rockwell methodClause 4.3 of this Standard

The Vickers method shall be used for any referee tests.

6.6 TESTING OF FUNCTIONAL CHARACTERISTICS

The functional characteristics of the bolt assembly shall be tested in accordance with

Table 6.7.

TABLE 6.7

TESTS FOR FUNCTIONAL CHARACTERISTICS OFBOLT ASSEMBLY

Functional characteristic Test Test procedure

Suitability for tensioning Assembly test Refer to Appendix D

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APPENDIX A

A DISCUSSION OF THE BASIS FOR ‘HR’ AND ‘HV’ SYSTEM TYPESIN THE EN 14399 SERIES

(Informative)

A1 CONTEXT

The European EN 14399 series introduced two parallel systems for achieving the necessary

ductility in tensioned (‘preloaded’) bolt, nut and washer assemblies. This was largely a

response to the two approaches implemented in Europe at the time. The HR (British/French)

and HV (German) systems adopted in the EN 14399 series reflect these two approaches.

A2 THE HR (BRITISH/FRENCH) SYSTEM

The HR system uses thick nuts and long thread lengths in the bolt assembly to obtainductility. The failure mechanism is predominantly by plastic elongation of the bolt, with

eventual tensile failure of the bolt shank, usually in the threaded portion. The longer thread

length is necessary to ensure that the induced strain is not localized.

A3 THE HV (GERMAN) SYSTEM

In contrast to the HR system, the HV system uses thinner nuts and shorter thread lengths to

obtain the required ductility by plastic deformation of the threads within the nut. The failure

mechanism is essentially local thread stripping.

A4 COMPARING THE SYSTEM BEHAVIOUR

HR bolts are relatively insensitive to overtightening during tensioning, although control isstill necessary to ensure gross overtightening and failure does not occur. Failure of the bolt

is predominantly by bolt breakage, which is readily detectable. The form of the failure

surface can indicate whether the bolt has failed in essentially pure tension (desirable) or

whether excessive torque (not desirable) has occurred. A failure due to torque may be

symptomatic of excessive binding of the nut on the bolt shank during the tensioning

operation, caused by factors such as galling of the galvanized coatings or bolts and nuts that

have been allowed to weather and rust before installation. Figure A1 indicates typical

failure modes for tension predominant and torque predominant failures respectively.

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(a) Tension predominant failure form (b) Torque predominant failure form

NOTE: Figure A1 provided courtesy of Research Council on Structural Connections.

FIGURE A1 FAILURE FORMS FOR HR BOLTS

HV bolts fail by thread deformation. It may be argued that in the event of failure by thread

plastic deformation, the assembly still acts as a non-tensioned assembly. HV assemblies are

more sensitive to over-tightening during tensioning and therefore require more site control.

The mode of failure by deformation of the engaged thread provides little indication of

failure.

A5 AUSTRALIAN AND NEW ZEALAND STANDARDS CONTEXT

The bolt and nut geometries in this Standard are most closely aligned with those of the HR

bolt system. Therefore, the ductility assumptions and methodology for bolting outlined in

AS 4100 and NZS 3404 has been based on performance requirements for bolts closely

aligned with the HR bolt system. Adoption of the HV bolt system would require review of

the performance requirements in AS 4100 and NZS 3404 and how those might be affected

by HV bolt system performance attributes.

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APPENDIX B

PRODUCT CONFORMITY

(Normative)

B1 SCOPE

This Appendix sets out the means by which product conformity evaluation can be

demonstrated by the manufacturer or supplier by—

(a) initial type testing (ITT); and

(b)

factory production control (FPC) including a minimum testing and inspection

frequency plan.

B2 INITIAL TYPE TESTING

B2.1 General

An initial type testing program shall be carried out in accordance with Paragraph B2.2

before the products are first placed onto the market.

Initial type testing shall be performed on first application of this Standard. Tests previously

performed in accordance with the provisions of this Standard (same product,

characteristic(s) test method, sampling procedure, system of attestation of conformity, etc.)

may be taken into account.

In addition, the initial type testing shall be performed at the beginning of a new method of

production or where using a new facility or equipment.

B2.2 Minimum sampling and testing plan

The initial type testing program comprises of routine testing at a higher frequency to

establish the capabilities of the manufacturing process to produce the product. The

minimum sampling and testing frequency plan for type testing is indicated in Table B1.

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TABLE B1

MINIMUM SAMPLING AND TESTING FREQUENCY PLAN FOR

INITIAL TYPE TESTING AND PRODUCTION TESTING

Characteristic

Applicable

Clause Sample size

Bolts

Dimensions 6.4.1 Refer Note

Minimum tensile strength 6.5.1 Refer Note

Stress at 0.2% non-proportional elongation 6.5.1 Refer Note

Stress under proof load 6.5.1 Refer Note

Percentage elongation after fracture for

machined test pieces

6.5.1 Refer Note

Percentage reduction of area after fracture

for machined test pieces

6.5.1 Refer Note

Head soundness 6.5.1 Refer Note

Hardness 6.5.1 Refer Note

Non-carburiza tion, HV 0.3 6.5 .1 Refer Note

Height of non-carburization thread zone 6.5.1 Refer Note

Depth of complete carburization in the

thread

6.5.1 Refer Note

Reduction of hardness after retempering,

HV

6.5.1 Refer Note

Breaking torque 6.5.1 Refer Note

Impact strength 6.5.1 Refer Note

Surface integrity 6.5.1 Refer Note

Nuts

Dimensions 6.4.2 Refer Note

Stress under proof load 6.5.2 Refer Note

Hardness 6.5.2 Refer Note

Washers

Dimensions 6.4.3 Refer Note 1

Hardness 6.5.3 Refer Note 1

Bolt assembly

Suitability for tensioning 6.6 Refer Note 1

k -class and k -factor 6.6 Refer Note 1

NOTE: Five tests for—

(a) each of four different nominal d iameters which should reflect the different

manufacturing methods;

(b) each property class (PC 8.8 only applicable to this Standard);

(c) each type of coating; and

(d) each type and source of material.

The results of all tests shall meet the requirements of this Standard.

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B3 FACTORY PRODUCTION CONTROL

B3.1 General

A factory production control (FPC) system shall be established, documented and maintained

to ensure that the products placed on the market conform to the stated performance

characteristics. The FPC system shall consist of procedures, regular inspections and testsand/or assessments, and the use of the results to control raw and other incoming material or

components, equipment, the production process and the product.

B3.2 Manufacturing controls

B3.2.1 Raw materials and components

The specification of all incoming raw materials shall be documented, as shall the inspection

scheme for ensuring their conformity.

B3.2.2 Manufacturing equipment

All equipment used in the manufacturing process shall be regularly inspected and

maintained to ensure use, wear or failure does not cause inconsistency in the manufacturing process. Inspections and maintenance shall be carried out and recorded in accordance with

the manufacturer’s written procedures.

B3.2.3 Traceability and marking

High-strength structural bolt assemblies, as well as their packaging, shall be identifiable

and traceable in respect to their manufacture. Procedures shall be established to ensure this.

Written procedures shall be utilized to ensure that processes related to affixing

identification and traceability codes are inspected regularly.

B3.2.4 Non-conforming product

Product identified as non-conforming shall be quarantined and disposed of. Documented

procedures shall be in place to record such non-conformance and actions taken.

B3.2.5 Corrective action

Documented procedures shall be established to instigate corrective action to eliminate the

cause of non-conformities.

B3.2.6 Surveillance auditing of the manufacturing process

Surveillance of the FPC shall be undertaken once per year. The surveillance audit shall

include the following:

(a) A review of the FPC test plans and production processes to identify if any changes

have occurred since the last audit, and their significance.

(b)

Checks to ensure that the production equipment is correctly maintained, serviced and

calibrated.

(c) A review of actions taken on any non-compliances.

B3.2.7 Modifications

Where modifications are made to the product, process or FPC system that may affect any of

the product characteristics defined in this Standard, all characteristics that may be affected

by the modification shall be subject to type testing in accordance with Paragraph B2.

The modifications, results of type testing and any re-assessment of the factory or FPC

system that may be required as a result of the modifications shall be reported.

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B3.3 Production testing

B3.3.1 Product testing and sampling plan

Procedures shall be established to ensure that the stated values of all the characteristics are

maintained.

The minimum sampling and testing frequency plan for FPC is indicated in Table B2.

TABLE B2

MINIMUM SAMPLING AND TESTING PLAN FOR

FACTORY PRODUCTION CONTROL

Characteristic Applicable Clause Sample size

Bolts

Head soundness 6.5.1 Refer Notes 1 and 3

Hardness 6.5.1 Refer Notes 1 and 3

Nuts

Stress under proof load 6.5.2 Refer Notes 1 and 4

Hardness 6.5.2 Refer Notes 1 and 4

Washers

Hardness 6.5.3 Refer Note 1

Bolt assembly

Suitability for tensioning 6.6 Refer Note 2

k-class and k-factor 6.6 Refer Note 2

NOTES:

1 One piece per hour for continuous heat treatment or one piece perbatch.

2 Five tests per bolt assembly lot.

3 Either head soundness or hardness may be tested.

4 Either stress under proof load or hardness may be tested.

The results of all tests shall meet the requirements of this Standard.

B3.3.2 Testing equipment

All weighing, measuring and testing equipment shall be calibrated and regularly inspected

according to documented procedures, frequencies and criteria.

B3.3.3 Recording and analysis of test resultsCompliant and non-compliant results of all testing conducted in accordance with the

established sampling and testing plan shall be recorded.

The test data shall be reviewed in a timely manner to ensure that all values obtained are

consistent with the product characteristics defined in this Standard or, where this is not the

case, any instance of non-compliance is investigated and that any non-conforming product

is dealt with in accordance with Paragraph B3.3.4 and that suitable corrective action is

taken in accordance with Paragraph B3.3.5.

B3.3.4 Review of the sampling and testing plan

An annual review shall be undertaken to establish that the sampling and testing plan is

being followed in all respects. The review shall take into account any changes to the product and/or production processes since the last review and their significance in terms of

the application of the sampling and testing plan.

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B3.3.5 Corrective actions

Where non-conforming product is identified, the corrective actions taken shall be recorded.

The results of the corrective actions shall be reviewed in a timely manner to ensure product

compliance has been re-established.

B4 NON-CONFORMING PRODUCT

B4.1 General

Non-conforming product shall be rejected and quarantined. There shall be written

procedures specifying the processing of non-conforming product.

B4.2 Retests

Retesting shall not be performed where testing to this Standard has proved non-

conformance.

B5 DOCUMENTATION

The results of all testing programs shall be recorded and such records shall be maintained

and be made available for inspection for a period of at least five years after the date when

that last product to which the test program refers to was delivered or the date the tests were

undertaken, whichever is later.

The following documentation shall be made available on request:

(a) Test results for initial type testing.

(b) Test results for factory production testing.

(c) Procedures for meeting the requirements, including sample size, for conducting initial

type testing as detailed in Paragraph B2.

(d)

Procedures for meeting the requirements, including sampling frequency, forconducting production testing as detailed in Paragraph B3.5.

(e) Procedures for meeting the requirements for manufacturing controls detailed in

Paragraph B3.

(f)

Procedures for non-conforming product as detailed in Paragraph B4.

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APPENDIX C

PURCHASING GUIDELINES

(Informative)

C1 GENERAL

Australian/New Zealand Standards are intended to include the technical provisions

necessary for the supply of materials referred to in the particular Standard, but do not

purport to comprise all the necessary provisions of a contract. In a number of cases, the

purchaser is asked to state the requirements or is given a choice of optional requirements.

These are contractual matters to be agreed upon between the purchaser and the

manufacturer or supplier.

This Appendix contains detailed explanations, advice and recommendations on the

information to be supplied by the purchaser at the time of enquiry and order. Its aims are to

avoid misunderstandings and to result in the purchaser receiving satisfactory products and

services.

C2 INFORMATION TO BE SUPPLIED BY THE PURCHASER

The purchaser should consider and supply the following information at the time of enquiry

and order, after making due reference to the explanation, advice and recommendations

contained in this Appendix and the requirements of this Standard:

(a)

Quantity, size and length.

(b) Delivery instructions (dates, schedules and delivery point).

(c)

Designation of property class and Standard number (see Clause 1.7).

(d)

Whether a test certificate is required (see Clause 6.1).

(e)

Any information concerning processing or end use that the purchaser considers of

assistance to the manufacturer or supplier.

(f) Any decorative or corrosion resistant coatings required, e.g. galvanizing or

electroplating (see Clause 1.8.5).

(g)

Whether any special testing conditions and procedures are necessary or required.

NOTES:

1 Any special or supplementary requirements additional to the requirement

as1252.1-2016 (draft)

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