EN 14399-7:2018

SLOVENSKI STANDARD
01-oktober-2018
1DGRPHãþD
SIST EN 14399-7:2008
9LVRNRWUGQRVWQHVWUXNWXUQHYLMDþQH]YH]H]DSUHGQDSHWMHGHO6LVWHP+5
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High-strength structural bolting assemblies for preloading - Part 7: System HR -
Countersunk head bolt and nut assemblies
Hochfeste vorspannbare Garnituren für Schraubverbindungen im Metallbau - Teil 7:
System HR - Garnituren aus Senkschrauben und Muttern
Boulonnerie de construction métallique à haute résistance apte à la précontrainte - Partie
7 : Système HR - Boulons à tête fraisée (vis + écrou)
Ta slovenski standard je istoveten z: EN 14399-7:2018
ICS:
21.060.10 Sorniki, vijaki, stebelni vijaki Bolts, screws, studs
21.060.20 Matice Nuts
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN 14399-7
EUROPEAN STANDARD
NORME EUROPÉENNE
July 2018
EUROPÄISCHE NORM
ICS 21.060.01 Supersedes EN 14399-7:2007
English Version
High-strength structural bolting assemblies for preloading
- Part 7: System HR - Countersunk head bolt and nut
assemblies
Boulonnerie de construction métallique à haute Hochfeste vorspannbare Garnituren für
résistance apte à la précontrainte - Partie 7 : Système Schraubverbindungen im Metallbau - Teil 7: System HR
HR - Boulons à tête fraisée (vis + écrou) - Garnituren aus Senkschrauben und Muttern
This European Standard was approved by CEN on 15 October 2017.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2018 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 14399-7:2018 E
worldwide for CEN national Members.

Contents Page
European foreword . 3
Introduction . 4
1 Scope . 6
2 Normative references . 6
3 Bolts . 7
3.1 Dimensions of bolts . 7
3.2 Specification for bolts and reference standard . 11
3.3 Marking of bolts . 11
4 Nuts . 12
4.1 Dimensions of nuts . 12
4.2 Specification for nuts and reference standards . 14
4.3 Proof load values of nuts . 15
4.4 Decarburisation of the nut thread . 15
4.5 Marking of nuts . 16
5 Designation of the bolt/nut assemblies . 16
6 Associated washers . 16
7 Functional characteristics of the bolt/nut/washer assembly . 17
7.1 General . 17
7.2 Maximum individual value of the bolt force during fitness for purpose test (F ) . 18
bi max
7.3 Values of angle Δθ . 18
7.4 Values of angle Δθ . 19
7.5 Individual values of the k-factor (k ), mean value of the k-factor (k ) and coefficient
i m
of variation of the k-factor (V ) . 19
k
7.5.1 Individual values of the k-factor (k ) for k-class K1 . 19
i
7.5.2 Mean value of the k-factor (k ) and coefficient of variation of the k-factor (V ) for k-
m k
class K2 . 19
Annex A (normative) Clamp lengths and grip lengths . 21
A.1 Clamp lengths for countersunk head bolting assemblies . 21
A.2 Grip lengths for countersunk head bolting assemblies . 24
Bibliography . 27

European foreword
This document (EN 14399-7:2018) has been prepared by Technical Committee CEN/TC 185
“Fasteners”, the secretariat of which is held by BSI.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by January 2019 and conflicting national standards shall
be withdrawn at the latest by January 2019.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN 14399-7:2007.
In comparison with EN 14399-7:2007, the following modifications have been made:
— Table 1 containing the overview of the composition of bolting assemblies and component marking
has been revised;
, was changed from 0,10 to 0,06;
— the coefficient of variation of the k-factor, Vk
— specifications for the designation of the bolting assemblies have been revised;
— Annex A with detailed specifications on clamp lengths and grip lengths has been added.
EN 14399 consists of the following parts, under the general title High-strength structural bolting
assemblies for preloading:
— Part 1: General requirements
— Part 2: Suitability for preloading
— Part 3: System HR — Hexagon bolt and nut assemblies
— Part 4: System HV — Hexagon bolt and nut assemblies
— Part 5: Plain washers
— Part 6: Plain chamfered washers
— Part 7: System HR — Countersunk head bolt and nut assemblies
— Part 8: System HV — Hexagon fit bolt and nut assemblies
— Part 9: System HR or HV — Direct tension indicators for bolt and nut assemblies
— Part 10: System HRC — Bolt and nut assemblies with calibrated preload
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta,
Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.
Introduction
This document on structural bolting reflects the situation in Europe where two technical solutions exist
to achieve the necessary ductility of bolt/nut/washer(s) assemblies. These solutions consist of two
different types (HR and HV) of bolt/nut/washer assemblies, see Table 1. Both types are well proven and
it is the responsibility of the experts using structural bolting whether they use the one or the other type.
It is, however, important for the performance of the assembly to avoid mixing up the components of
both types. Therefore, bolts and nuts for both types are standardized in one single part of this draft
European Standard each and the marking of the components of the bolting assemblies is uniform.
Preloaded bolted assemblies are very sensitive to differences in manufacture and lubrication.
Therefore, it is important that the bolting assemblies are supplied by one manufacturer, who is always
responsible for the functionality of the bolting assemblies as supplied.
For the same reason it is important that the coating of the bolting assemblies is under the control of one
manufacturer.
Beside the mechanical properties of the components, the functionality of the bolting assemblies
requires that the specified preload can be achieved if the bolting assemblies are tightened with a
suitable procedure. For this purpose, a test method for the suitability of the bolting assemblies for
preloading was created, which will demonstrate whether the functionality of the bolting assemblies is
fulfilled.
Table 1 — Composition of high-strength structural bolting assemblies and component marking
Type of bolting assembly System HR System HV System HRC
General requirements EN 14399-1
Suitability for preloading EN 14399-2 and, if any, additional testing specified in the product standard
Bolt and nut
EN 14399-3 EN 14399-7 EN 14399-4 EN 14399-8 EN 14399-10
Bolt HR8.8 HR10.9 HR8.8 HR10.9 HV10.9 HVP10.9 HRC10.9
HR8 HR8
Nut or HR10 or HR10 HV10 HV10 HR10 HRD10
HR10 HR10
a
EN 14399-5
a
Washer(s) EN 14399-5 or EN 14399-6 EN 14399-6
or EN 14399-6
b
H or HR
b b b
Marking H or HR H or HV H or HR
c
or HD
Direct tension indicator
and nut face washer or EN 14399-9
bolt face washer, if any
Direct tension
H8 H10 H8 H10 H10
indicator
Not applicable
Nut face washer HN HN
bolt face washer HB Not applicable HB
a
EN 14399-5 can only be used under the nut.
b
At the choice of the manufacturer.
c
Mandatory mark for washers with enlarged outer diameter according to EN 14399-5 only.

Marking
Marking
1 Scope
This European Standard specifies, together with EN 14399-1 and EN 14399-2, the requirements for
assemblies of high-strength structural countersunk bolts and nuts of system HR suitable for preloaded
joints with thread sizes M12 to M36 and property classes 8.8/8 or 8.8/10 and 10.9/10.
Bolting assemblies in accordance with this document have been designed to allow preloading of at least
1)
0,7 f × A according to EN 1993-1-8 (Eurocode 3) and to obtain ductility predominantly by plastic
ub s
elongation of the bolt. For this purpose the components have the following characteristics:
— regular nut height according to style 1, see EN ISO 4032;
— thread length of the bolt according to ISO 888.
Bolting assemblies in accordance with this document include washers according to EN 14399-6 or to
EN 14399-5.
NOTE Attention is drawn to the importance of ensuring that bolting assemblies are correctly used if
satisfactory results are to be obtained. For recommendations concerning proper application, reference to
EN 1090-2 is made.
General requirements and requirements for suitability for preloading are specified in EN 14399-2.
Clamp lengths and grip lengths for the bolting assemblies are specified in the normative Annex A.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.
EN 14399-1, High-strength structural bolting assemblies for preloading - Part 1: General requirements
EN 14399-2, High-strength structural bolting assemblies for preloading - Part 2: Suitability for preloading
EN 14399-5, High-strength structural bolting assemblies for preloading - Part 5: Plain washers
EN 14399-6, High-strength structural bolting assemblies for preloading - Part 6: Plain chamfered washers
...