SIST EN 3818:2019

Aerospace series - Bolts, MJ threads, in titanium alloy TI-P64001 - Strength class: 1 100 MPa (at ambient temperature) - Technical specification

This European standard specifies the characteristics, qualification and acceptance requirements for
bolts with MJ threads in TI-P64001, for aerospace applications.
Strength class: 1 100 MPa1.
It is applicable whenever referenced.

Luft- und Raumfahrt - Schrauben, MJ-Gewinde, aus Titanlegierung TI-P64001 - Festigkeitsklasse: 1 100 MPa (bei Raumtemperatur) - Technische Lieferbedingungen

Diese Europäische Norm legt die Eigenschaften sowie die Qualifikations- und Annahmeanforderungen für Schrauben mit MJ-Gewinde aus TI-P64001 für Anwendungen in der Luft- und Raumfahrt fest.
Festigkeitsklasse: 1 100 MPa .
Die Norm ist immer dann anzuwenden, wenn auf sie Bezug genommen wird.

Série aérospatiale - Vis à filetage MJ, en alliage de titane TI-P64001 - Classe de résistance : 1 100 MPa (à température ambiante) - Spécification technique

La présente norme européenne spécifie les caractéristiques, les exigences de qualification et de réception des vis à filetage MJ en TI-P64001, pour applications aérospatiales.
Classe de résistance : 1 100 MPa .
Elle est applicable chaque fois qu'elle est citée en référence.

Aeronavtika - Sorniki, navoj MJ, iz titanove zlitine TI-P64001 - Trdnostni razredi: 1100 MPa (pri okoljski temperaturi) - Tehnična specifikacija

Ta evropski standard določa karakteristike ter zahteve glede kvalifikacije in sprejemljivosti za sornike z navojem MJ iz TI-P64001, za uporabo v aeronavtiki.
Razred trdnosti: 1 100 MPa1.
Uporablja se, kadar je naveden.

General Information

• Status: Published
• Publication Date: 27-May-2019
• ICS: 21.060.10 - Bolts, screws, studs
• ICS: 49.025.30 - Titanium
• ICS: 49.030.20 - Bolts, screws, studs
• Technical Committee: I13 - Imaginarni 13
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 20-May-2019
• Due Date: 25-Jul-2019
• Completion Date: 28-May-2019
• Ref Project: EN 3818:2019 - Aerospace series - Bolts, MJ threads, in titanium alloy TI-P64001 - Strength class: 1 100 MPa (at ambient temperature) - Technical specification

Relations

• Replaces: SIST EN 3818:2005 - Aerospace series - Bolts, MJ threads, in titanium alloy TI-P64001 - Strength class: 1 100 MPa (at ambient temperature) - Technical specification
• Effective Date: 15-May-2019
• Revised: SIST EN 3818:2005 - Aerospace series - Bolts, MJ threads, in titanium alloy TI-P64001 - Strength class: 1 100 MPa (at ambient temperature) - Technical specification
• Effective Date: 14-Jun-2017

Overview

EN 3818:2019 is a CEN (European) technical specification for aerospace bolts with MJ threads manufactured from titanium alloy TI‑P64001, strength class 1 100 MPa (at ambient temperature). The standard defines material, manufacturing, metallurgical, mechanical and inspection requirements, together with qualification and batch acceptance procedures for bolts intended for aerospace use. EN 3818:2019 supersedes EN 3818:2004 and is applicable whenever referenced in procurement or design documentation.

Key topics and requirements

• Material and strength class
  • Bolts made from TI‑P64001 titanium alloy with a minimum tensile strength classification of 1 100 MPa at ambient temperature.
• Manufacturing
  • Hot forging of heads prior to heat treatment; strict control of forging and heat‑treatment routes.
  • Threads to be produced by single rolling after full heat treatment.
  • Head‑to‑shank fillet cold‑rolled after heat treatment to produce beneficial surface work and meet dimensional limits.
• Metallurgical and microstructure controls
  • Macroscopic and microscopic examinations to verify grain flow in fillet and thread areas.
  • Limits on overheating depth in the head and strict control of surface contamination.
  • Hydrogen content limit on material removed from the head (≤ 0,0125 % as specified).
• Mechanical testing
  • Tensile testing per ISO 6892‑1 (unless specifically exempted).
  • Tension fatigue life requirements (example values given): mean ≥ 65 000 cycles, individual ≥ 45 000 cycles, max 130 000 cycles; frequency ≤ 140 Hz (tests per ISO 7961).
  • Recess removal torque and other functional tests for driven features.
• Surface and coating
  • Surface roughness and coatings as defined by the product/definition document and assessed per ISO 4288 and applicable coating standards.
  • Non‑destructive testing such as fluorescent penetrant inspection (per ISO 3452‑1) for surface discontinuities.
• Quality assurance and sampling
  • Qualification procedure for each bolt type/diameter, with qualification inspection on representative samples (e.g., 20 bolts from a single batch).
  • Acceptance inspections performed on every production batch using statistically based sampling (ISO 2859‑1 referenced).

Applications and users

• Intended for aerospace manufacturers, fastener suppliers, procurement/specification engineers, quality/inspection teams and certification bodies who need to:
  • Specify and procure high‑strength titanium MJ‑thread bolts for airframe and aerospace assemblies.
  • Establish production controls, acceptance plans and test programs for titanium fasteners.
  • Ensure metallurgical integrity, fatigue performance and traceability of aerospace bolts.

Related standards (referenced)

• ISO 2859‑1 (sampling procedures, AQL)
• ISO 3452‑1 (penetrant testing)
• ISO 4288 (surface texture)
• ISO 5855‑2 (MJ thread limit dimensions)
• ISO 6892‑1 (tensile testing)
• ISO 7961 (aerospace bolt test methods)

Keywords: EN 3818:2019, MJ threads, TI‑P64001, titanium bolts, aerospace fasteners, strength class 1100 MPa, bolt qualification, fatigue testing, tensile testing, non‑destructive testing.

Standards Content (Sample)

SLOVENSKI STANDARD
01-julij-2019
Nadomešča:
SIST EN 3818:2005
Aeronavtika - Sorniki, navoj MJ, iz titanove zlitine TI-P64001 - Trdnostni razredi:
1100 MPa (pri okoljski temperaturi) - Tehnična specifikacija
Aerospace series - Bolts, MJ threads, in titanium alloy TI-P64001 - Strength class: 1 100
MPa (at ambient temperature) - Technical specification
Luft- und Raumfahrt - Schrauben, MJ-Gewinde, aus Titanlegierung TI-P64001 -
Festigkeitsklasse: 1 100 MPa (bei Raumtemperatur) - Technische Lieferbedingungen
Série aérospatiale - Vis à filetage MJ, en alliage de titane TI-P64001 - Classe de
résistance : 1 100 MPa (à température ambiante) - Spécification technique
Ta slovenski standard je istoveten z: EN 3818:2019
ICS:
21.060.10 Sorniki, vijaki, stebelni vijaki Bolts, screws, studs
49.025.30 Titan Titanium
49.030.20 Sorniki, vijaki, stebelni vijaki Bolts, screws, studs
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN 3818
EUROPEAN STANDARD
NORME EUROPÉENNE
May 2019
EUROPÄISCHE NORM
ICS 49.030.20 Supersedes EN 3818:2004
English Version
Aerospace series - Bolts, MJ threads, in titanium alloy TI-
P64001 - Strength class: 1 100 MPa (at ambient
temperature) - Technical specification
Série aérospatiale - Vis à filetage MJ, en alliage de titane Luft- und Raumfahrt - Schrauben, MJ-Gewinde, aus
TI-P64001 - Classe de résistance : 1 100 MPa (à Titanlegierung TI-P64001 - Festigkeitsklasse: 1 100
température ambiante) - Spécification technique MPa (bei Raumtemperatur) - Technische
Lieferbedingungen
This European Standard was approved by CEN on 2 December 2018.

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
© 2019 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 3818:2019 E
worldwide for CEN national Members.

Contents
Page
European foreword . 3
1 Scope . 4
2 Normative references . 4
3 Terms and definitions . 4
4 Quality assurance . 6
5 Requirements . 7
Bibliography . 24

European foreword
This document (EN 3818:2019) has been prepared by the Aerospace and Defence Industries
Association of Europe - Standardization (ASD-STAN).
After enquiries and votes carried out in accordance with the rules of this Association, this Standard has
received the approval of the National Associations and the Official Services of the member countries of
ASD, prior to its presentation to CEN.
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 November 2019, and conflicting national standards
shall be withdrawn at the latest by November 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 3818:2004.
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.
1 Scope
This European standard specifies the characteristics, qualification and acceptance requirements for
bolts with MJ threads in TI-P64001, for aerospace applications.
Strength class: 1 100 MPa .
It is applicable whenever referenced.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 2859-1, Sampling procedures for inspection by attributes — Part 1: Sampling schemes indexed by
acceptance quality limit (AQL) for lot-by-lot inspection
ISO 3452-1, Non-destructive testing — Penetrant testing — Part 1: General principles
ISO 4288, Geometrical Product Specifications (GPS) — Surface texture: Profile method — Rules and
procedures for the assessment of surface texture
ISO 5855-2, Aerospace — MJ threads — Part 2: Limit dimensions for bolts and nuts
ISO 6892-1, Metallic materials — Tensile testing — Part 1: Method of test at room temperature
ISO 7961, Aerospace — Bolts — Test methods
3 Terms and definitions
For the purposes of this standard the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— IEC Electropedia: available at http://www.electropedia.org/
— ISO Online browsing platform: available at http://www.iso.org/obp
3.1
batch
quantity of finished bolts, of the same type and same diameter, produced from a material obtained from
the same melt, manufactured in the course of the same production cycle, following the same
manufacturing route and having undergone all the relevant heat treatments and surface treatments
3.2
inspection lot
quantity of bolts from a single production batch with the same part number which completely defines
the bolt
1 Minimum tensile strength of the material at ambient temperature
3.3
Surface discontinuities
3.3.1
crack
rupture in the material which may extend in any direction and which may be intercrystalline or
transcrystalline in character
3.3.2
seam
open surface defect
3.3.3
lap
surface defect caused by folding over metal fins or sharp corners and then compressing them into the
surface
3.3.4
inclusions
non-metallic particles originating from the material manufacturing process. These particles may be
isolated or arranged in strings
3.4
simple random sampling
taking of n items from a population of N items in such a way that all possible combinations of n items
have the same probability of being chosen
3.5
major defect
defect, other than critical, that is likely to result in a failure or to reduce materially the usability of the
considered product for its intended purpose
3.6
minor defect
defect that is not likely to reduce materially the usability of the considered product for its intended
purpose, or that is a departure from established specification having little bearing on the effective use
or operation of this product
3.7
sampling plan
plan according to which one or more samples are taken in order to obtain information and possibly to
reach a decision
3.8
limiting quality
LQ
in a sampling plan, the quality level which corresponds to the specified 10 % probability of acceptance
3.9
Acceptance Quality Limit
AQL
quality limit which in a sampling plan corresponds to a specified but relatively high probability of
acceptance. It is the maximum per cent defective (or the maximum number of defects per hundred
units) that, for purposes of sampling inspection can be considered satisfactory as a process average.
3.10
finished bolt
bolt ready for use, inclusive of any possible treatments and/or surface coatings, as specified in the
product standard or definition document
3.11
definition document
document specifying all the requirements for finished bolts
4 Quality assurance
4.1 Qualification
The qualification procedure for aerospace standard products (e. g. according to EN 9133 or an
equivalent aerospace accepted and established qualification procedure) shall be used and documented
according to the specified tests if not otherwise agreed between customer and supplier.
Qualification inspections and tests (requirements, methods, numbers of bolts) are specified in Table 1.
They shall be carried out on:
— each type and diameter of bolt;
— 20 bolts selected from a single batch by simple random sampling.
The test programme may possibly be reduced, or the qualification be granted without inspection or
testing. Any such decision shall be based on the results obtained on similar types and diameters of bolts
provided that the design and manufacturing conditions are identical.
Table 2 indicates the allocation of bolt samples for the inspections and tests.
4.2 Acceptance
4.2.1 Purpose
The purpose of acceptance inspections and tests is to check, as simply as possible, by a method
representative of actual use conditions, with the uncertainty inherent to statistical sampling, that the
bolts constituting the batch satisfy the requirements of this standard.
4.2.2 Conditions
Acceptance inspections and tests (requirements, methods, numbers of bolts) are specified in Table 1.
They shall be carried out on each batch. Bolts from the batch to be tested shall be selected by simple
random sampling.
Each bolt may be submitted to several inspections or tests.
If a more stringent inspection is deemed necessary, all or part of the qualification inspections and tests
may be performed during the acceptance inspection and testing. In this case, the number of bolts
submitted to these inspections and tests is the same as that submitted for qualification inspection and
tests.
4.2.3 Responsability
Acceptance inspections and tests shall be carried out by the manufacturer, or under his responsibility.
4.2.4 Inspection and test report
A test report showing actual numerical values shall be provided if specified in the purchase order.
5 Requirements
See Table 1.
Table 1 — Technical requirements and test methods
a
Clause Characteristic Requirement Inspection and test Sample
Q/A
method size
5.1 Q
Material In accordance with the product standard Chemical analysis or
or definition document. certificate of conformity
A
issued by the
manufacturer of the semi-
finished product
5.2 Standard gauging Q 15
Dimensions, In accordance with the product standard
tolerances and or definition document.
A Table 3
tolerances of form
and
and position Table 4
5.3 Manufacturing
5.3.1 Forging The head of the bolts shall be forged by a According to the route of Q

hot forging process before heat treatment. manufacture

The equipment shall ensure a uniform The equipment shall be
temperature throughout the batch. approved.
5.3.2 Heat treatment Q
The forged blanks shall be heat treated to According to process
produce the properties required by the control

definition document.
Blanks shall not be heat treated more than The equipment shall be
twice. approved.
5.3.3
Removal of surface No sign of surface contamination or Visual examination
contamination oxidation.
(bearing face and
If machining is required the requirements
shank)
of 5.5.1 shall be respected.
a
Clause Characteristic Requirement Inspection and test Sample
Q/A
method size
5.3.4 Head to shank fillet Q 5
The fillet radius shall be cold rolled after Visual examination at a
heat treatment and machining so as to suitable magnification of
A Table 3
remove all visual signs of machining and × 10 to × 20 and and
to create superficial cold working. The dimensional check Table 4
deformation shall not exceed the values in
Figure 1.
The requirements apply on bolts except
on the following:
a) threaded to head bolts;
b) bolts with a nominal diameter
< 5 mm.
Q
5.3.5 Threads Formed by a single rolling process after According to the route of
full heat treatment. manufacture.
5.3.6 Q 5
Surface roughness In accordance with the product standard ISO 4288
or definition document.
A Table 3
Visual examination
and
Table 4
5.3.7 Surface coating Q 5
In accordance with the product standard See applicable coating
or definition document. standard.
A Table 3
and
Table 4
5.4 Mechanical
A test sample selected from each diameter
properties
of bar or wire from each cast shall be heat
treated together with a production batch
of bolts.
The sample selected shall be sufficient to
provide tensile test pieces. The test
specimens shall meet the mechanical
properties required by the material
standard.
Q 5
5.4.1 Tensile strength If stress durability is necessary, see 5.5.6, ISO 7961 for bolts
then tensile test is not carried out.
A Table 6 or
ISO 6892-1 for test
The applicable tensile loads are specified
Table 7
specimens
in Table 5.
This test applies on bolt, except on the
following cases, but failure in the bearing
face and shank zone is not permissible:
a) protruding head bolts of grip length
< twice the nominal shank diameter;
b) countersunk head bolts of grip
length < × 2,5 the nominal shank
diameter;
c) threaded to head bolts of overall
length < × 3 the nominal shank
diameter or bolts having an overall
length < 18 mm;
d) bolts with a thread length
< 1,5 times the thread nominal
diameter;
e) bolts of diameters of < 4 mm.
a
Clause Characteristic Requirement Inspection and test Sample
Q/A
method size
5.4.2 Life: ISO 7961 Q 5
Tension fatigue
strength
— mean value:
min. 65 000 cycles.
— individual value:
min. 45 000 cycles;
max. 130 000 cycles.
Frequency: 140 Hz max.
Loads: see Table 5.
This test applies on bolts except on the
following:
a) protruding head bolts of grip length
< twice the nominal shank diameter;
b) countersunk head bolts of grip length
< × 2,5 the nominal shank diameter;
c) bolts with a nominal diameter
< 5 mm;
d) threaded to head bolts.
For individual fatigue life values
exceeding 65 000 cycles, breaking may
occur in any place.
For individual fatigue
...