SIST EN 16602-70-46:2015
(Main)Space product assurance - Requirements for manufacturing and procurement of threaded fasteners
Space product assurance - Requirements for manufacturing and procurement of threaded fasteners
This Standard defines the requirements for manufacturing, provision, inspection and quality control of highquality threaded fastening
devices (bolts, nuts, studs and screws) hereafter referred to as threaded fasteners or fasteners, used in space hardware.
This Standard does not include a complete review of the factors relevant to the fabrication of high quality threaded fasteners. It provides
the definition of the technical requirements and quality control procedures to be applied in the fabrication and supply of threaded
fasteners for spacecraft applications.
Fasteners for spacecraft applications are those aerospace standard fasteners (i.e. in accordance with LN, DIN or other national or international aerospace standards), or those fasteners meeting or exceeding the requirements in ISO 4759 1 for “Product grade A”, which also fulfil the requirements for space applications as specified in the present document.
Raumfahrtproduktsicherung - Anforderungen für die Herstellung und Beschaffung von eingezogenen Klemmen/Befestigern
Assurance produit des projets spatiaux - Exigences pour la fabrication et l'approvisionnement de fixations filetées
La présente norme définit les exigences relatives à la fabrication, l'approvisionnement, l'inspection et le contrôle qualité de dispositifs d'assemblage filetés de haute qualité (boulons, écrous, goujons et vis) ci-après dénommés fixations filetées ou éléments de fixation, utilisés dans le matériel spatial.
La présente norme ne comprend pas une présentation exhaustive des facteurs importants pour la fabrication d'éléments de fixation filetés de haute qualité. Elle donne la définition des exigences techniques et des procédures de contrôle qualité à appliquer dans la fabrication et la fourniture de fixations filetées pour applications spatiales.
Les éléments de fixation pour applications spatiales sont les éléments de fixation habituelles (c'est-à-dire conformes aux normes LN, DIN ou aux autres normes aérospatiales nationales ou internationales), ou les éléments de fixation au minimum conformes aux exigences de la norme ISO 4759 1 pour la « qualité de produit A », répondant également aux exigences pour applications spatiales telles que spécifiées au présent document.
Zagotavljanje varnih proizvodov v vesoljski tehniki - Zahteve za izdelavo in preskrbo vijačnih zvez
Ta standard določa zahteve za izdelavo, preskrbo, inšpekcijske preglede in nadzor kakovosti visoko kakovostnih vijačnih veznih elementov (vijakov in matic), v nadaljnjem besedilu vijačnih zvez ali zvez, ki se uporabljajo za vesoljsko strojno opremo. Ta standard ne zajema popolnega pregleda dejavnikov, pomembnih za izdelavo visoko kakovostnih vijačnih zvez. Zagotavlja definicijo tehničnih zahtev in postopkov za nadzor kakovosti, ki se uporabljajo pri izdelovanju in preskrbi vijačnih zvez za vesoljska plovila. Zveze za vesoljska plovila so tiste aeronavtične standardne zveze (tj. v skladu z LN, DIN ali drugimi nacionalnimi ali mednarodnimi aeronavtičnimi standardi) ali tiste zveze, ki izpolnjujejo ali presegajo zahteve iz standarda ISO 4759-1 za »razred izdelave A«, ki izpolnjujejo tudi zahteve za vesoljske uporabe, kot je določeno v tem dokumentu.
General Information
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN 16602-70-46:2015
01-januar-2015
=DJRWDYOMDQMHYDUQLKSURL]YRGRYYYHVROMVNLWHKQLNL=DKWHYH]DL]GHODYRLQ
SUHVNUERYLMDþQLK]YH]
Space product assurance - Requirements for manufacturing and procurement of
threaded fasteners
Raumfahrtproduktsicherung - Anforderungen für die Herstellung und Beschaffung von
eingezogenen Klemmen/Befestigern
Assurance produit des projets spatiaux - Exigences pour la fabrication et
l'approvisionnement de fixations filetées
Ta slovenski standard je istoveten z: EN 16602-70-46:2014
ICS:
49.030.01 Vezni elementi na splošno Fasteners in general
SIST EN 16602-70-46:2015 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN 16602-70-46:2015
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SIST EN 16602-70-46:2015
EUROPEAN STANDARD
EN 16602-70-46
NORME EUROPÉENNE
EUROPÄISCHE NORM
October 2014
ICS 49.030.01; 49.140
English version
Space product assurance - Requirements for manufacturing and
procurement of threaded fasteners
Assurance produit des projets spatiaux - Exigences pour la Raumfahrtproduktsicherung - Anforderungen für die
fabrication et l'approvisionnement de fixations filetées Herstellung und Beschaffung von eingezogenen
Klemmen/Befestigern
This European Standard was approved by CEN on 18 October 2014.
CEN and CENELEC 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 and CENELEC
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 and CENELEC member into its own language and notified to the CEN-CENELEC Management Centre
has the same status as the official versions.
CEN and CENELEC members are the national standards bodies and national electrotechnical committees 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, Slovakia,
Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom.
CEN-CENELEC Management Centre:
Avenue Marnix 17, B-1000 Brussels
© 2014 CEN/CENELEC All rights of exploitation in any form and by any means reserved Ref. No. EN 16602-70-46:2014 E
worldwide for CEN national Members and for CENELEC
Members.
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SIST EN 16602-70-46:2015
EN 16602-70-46:2014 (E)
Table of contents
Foreword . 4
1 Scope . 5
2 Normative references . 6
3 Terms, definitions and abbreviated terms . 8
3.1 Terms defined in other standards . 8
3.2 Terms specific to the present standard . 8
3.3 Abbreviated terms. 9
4 Requirements . 10
4.1 Fabrication . 10
4.1.1 General . 10
4.1.2 Raw material . 10
4.1.3 Head forming . 10
4.1.4 Heat treatment . 11
4.1.5 Head-to-shank fillet rolling . 11
4.1.6 Threads . 11
4.1.7 Identification marking . 12
4.1.8 Surface treatment . 12
4.1.9 Workmanship, handling and packaging . 12
4.2 Dimensional and metallurgical requirements. 13
4.2.1 General . 13
4.2.2 Nominal dimensions . 13
4.2.3 Head-to-shank fillet . 13
4.2.4 Non-destructive inspections . 14
4.2.5 Metallurgical examination . 15
4.2.6 Measurement of hydrogen content . 16
4.2.7 Outgassing and offgassing . 16
4.3 Mechanical testing . 17
4.3.1 General . 17
4.3.2 Hardness test . 17
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EN 16602-70-46:2014 (E)
4.3.3 Tensile test . 18
4.3.4 Shear test . 19
4.3.5 Fatigue test . 20
4.3.6 Creep test . 20
4.3.7 Corrosion test . 22
4.3.8 Stress-corrosion test . 22
4.4 Quality assurance . 23
4.4.1 General . 23
4.4.2 Quality requirements . 23
Annex A (normative) Customer specification document for threaded
fasteners – DRD . 26
Annex B (normative) Product conformance report (PCR) – DRD . 28
Annex C (informative) Inspection levels, acceptance quality limits (AQL)
and limiting quality levels (LQ) for inspection of fasteners . 30
Bibliography . 32
Figures
Figure 4-1: Tolerance of head-to-shank fillet profile . 14
Figure 4-2: Location of microsections for metallurgical examination . 15
Figure 4-3: Area delimiting interruptions in grain flow in the head-to-shank region . 16
Figure 4-4: Example of a regular grain flow in a threaded surface . 16
Figure 4-5: Locations for hardness testing (indicated with cross symbol) . 18
Figure 4-6: Loading schematic for tensile testing of threaded fasteners . 21
Figure 4-7: Schematic of an example of double-shear loading jigs . 22
Tables
Table 4-1: Maximum allowed values of the extension C of the distorted area shown in
Figure 4-1 . 14
Table C- 1: Inspection levels, acceptance quality limits (AQL) and limiting quality levels
(LQ) for inspection of fasteners . 30
3
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SIST EN 16602-70-46:2015
EN 16602-70-46:2014 (E)
Foreword
This document (EN 16602-70-46:2014) has been prepared by Technical
Committee CEN/CLC/TC 5 “Space”, the secretariat of which is held by DIN.
This standard (EN 16602-70-46:2014) originates from ECSS-Q-ST-70-46C Rev.1.
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 April 2015,
and conflicting national standards shall be withdrawn at the latest by April
2015.
Attention is drawn to the possibility that some of the elements of this document
may be the subject of patent rights. CEN [and/or CENELEC] shall not be held
responsible for identifying any or all such patent rights.
This document has been prepared under a mandate given to CEN by the
European Commission and the European Free Trade Association.
This document has been developed to cover specifically space systems and has
therefore precedence over any EN covering the same scope but with a wider
domain of applicability (e.g. : aerospace).
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,
Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United
Kingdom.
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EN 16602-70-46:2014 (E)
1
Scope
This Standard defines the requirements for manufacturing, provision,
inspection and quality control of high-quality threaded fastening devices (bolts,
nuts, studs and screws) hereafter referred to as threaded fasteners or fasteners,
used in space hardware.
This Standard does not include a complete review of the factors relevant to the
fabrication of high quality threaded fasteners. It provides the definition of the
technical requirements and quality control procedures to be applied in the
fabrication and supply of threaded fasteners for spacecraft applications.
Fasteners for spacecraft applications are those aerospace standard fasteners (i.e.
in accordance with LN, DIN or other national or international aerospace
standards), or those fasteners meeting or exceeding the requirements in
ISO 4759-1 for “Product grade A”, which also fulfil the requirements for space
applications as specified in the present document.
5
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EN 16602-70-46:2014 (E)
2
Normative references
The following dated normative documents are called by the requirements of
this ECSS Standard and therefore constitute requirements to it. Subsequent
amendments to, or revisions of any of these publications do not apply.
NOTE However, parties to agreements based on this
ECSS Standard are encouraged to investigate the
possibility of applying the most recent editions of
the normative documents indicated below.
EN reference Reference in text Title
EN 16601-00-01 ECSS-S-ST-00-01C ECSS system – Glossary of terms
EN 16603-30-01 ECSS-E-ST-30-01C Space engineering — Fracture control
EN 16602-70 ECSS-Q-ST-70C Space product assurance — Materials, parts and
processes
EN 16602-70-02 ECSS-Q-ST-70-02C Space product assurance — Thermal vacuum
outgassing test for the screening of space materials
EN 16602-70-29 ECSS-Q-ST-70-29C Space product assurance — The determination of
offgassing products from materials and assembled
articles to be used in a manned space vehicle crew
compartment
EN 16602-70-36 ECSS-Q-ST-70-36C Space product assurance — Material selection for
controlling stress-corrosion cracking
EN 16602-70-37 ECSS-Q-ST-70-37C Space product assurance — Determination of the
susceptibility of metals to stress— corrosion cracking
EN 16602-70-71 ECSS-Q-ST-70-71C Space product assurance — Data for selection of
space materials
ISO 204 Metallic materials — Uninterrupted uniaxial creep
testing in tension — Method of test
ISO 225 Fasteners — Bolts, screws, studs and nuts — Symbols
and designations of dimensions
ISO 1502 ISO general — purpose metric screw threads —
Gauges and gauging
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EN reference Reference in text Title
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 2859-2 Sampling procedures for inspection by attributes,
Part 2: Sampling plans indexed by limiting quality
(LQ), for isolated lots inspection
ISO 3353-1:2002 Aerospace — Lead and runout threads — Part 1:
Rolled external threads
ISO 3800 Threaded fasteners – Axial load fatigue testing – Test
methods and evaluation of results
ISO 4759-1 Tolerances for fasteners — Part 1: Bolts, screws, studs
and nuts — Product grades A, B and C
ISO 6157-2 Fasteners — Surface discontinuities – Part 2: Nuts
ISO 6157-3 Fasteners – Surface discontinuities – Part 3: Bolts,
screws and studs for special requirements
ISO 6506-1 Metallic materials — Brinell hardness test — Part 1:
Test method
ISO 6506-2 Metallic materials — Brinell hardness test — Part 2:
Verification and calibration of testing machines
ISO 6506-3 Metallic materials — Brinell hardness test — Part 3:
Calibration of reference blocks
ISO 6507-1 Metallic materials — Vickers hardness test – Part 1:
Test method
ISO 6507-2 Metallic materials — Vickers hardness test — Part 2:
Verification and calibration of testing machines
ISO 6507-3 Metallic materials — Vickers hardness test — Part 3:
Calibration of reference blocks
ISO 6508-1 Metallic materials — Rockwell hardness test — Part
1: Test method
ISO 6508-2 Metallic materials — Rockwell hardness test — Part
2: Verification and calibration of testing machines
ISO 6508-3 Metallic materials — Rockwell hardness test — Part
3: Calibration of reference blocks
ISO 9140 Aerospace – Nuts, plain or slotted (castellated) – Test
methods
DIN ISO 9152 Aerospace – Bolts, with MJ Threads, in Titanium
alloys, strength class 1100 MPa – Procurement
specification
ASTM B 117-07a Standard practice for operating salt spray (fog)
apparatus
ASTM E 1417-05e1 Standard practice for liquid penetrant testing
ASTM E 1444-05 Standard practice for magnetic particle testing
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EN 16602-70-46:2014 (E)
3
Terms, definitions and abbreviated terms
3.1 Terms defined in other standards
For the purpose of this Standard, the terms and definitions from ECSS-S-ST-00-01
and ECSS-Q-ST-70 apply.
3.2 Terms specific to the present standard
3.2.1 bolt
cylindrical screwed bar provided with a head, generally not threaded along its
entire length
NOTE For example: Shank plus threaded portion.
3.2.2 fail-safe
approach in which the structure is designed with sufficient structural
redundancy to ensure that the failure of one structural element does not cause
general failure of the entire structure
3.2.3 fastener
device used to hold parts firmly together in an assembly
3.2.4 galling
condition whereby excessive friction between high spots results in localized
welding with subsequent splitting and a further roughening of rubbing surfaces
of one or both or two mating parts
3.2.5 nut
metal collar, screwed internally, to fit a bolt
NOTE Usually hexagonal in shape and operated by a
spanner.
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3.2.6 safe-life
approach which requires that the largest undetected defect that can exist in the
structure does not grow to failure when subjected to loads and environments
encountered in service
3.2.7 sampling plan
combination of sample size to be used with associated batch acceptability
criteria
3.2.8 shank
unthreaded portion of the cylindrical screwed bar of a bolt
3.2.9 stud
shank, or endless bolt, externally screwed from one end, both ends or along its
entire length
3.2.10 (screw) thread
helical ridge of approximately triangular, square or rounded section, formed on
a cylindrical core, the pitch and core diameter being standardised under various
systems
3.2.11 threaded fastener
device composed by a cylindrical screwed bar provided with a head and a
metal collar, screwed internally, to fit the cylindrical bar that is used to hold
parts firmly together in an assembly
3.3 Abbreviated terms
For the purpose of this Standard, the abbreviated terms from ECSS-S-ST-00-01C
and the following apply:
Abbreviation Meaning
AQL acceptance quality level
ASTM American Society for Testing and Materials
HB Brinell hardness
HRC Rockwell hardness
HV Vickers hardness
ISO International Organization for Standardization
LQ limiting quality
PCR product conformance report
PVC polyvinyl chloride
RMC raw material certificate
UTS ultimate tensile strength
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EN 16602-70-46:2014 (E)
4
Requirements
4.1 Fabrication
4.1.1 General
a. The customer shall establish a specification document in conformance
with the DRD in Annex A.
b. The manufacturer shall have a quality assurance system.
c. The manufacturer shall verify and assure conformance during
production to the technical requirements specified in this clause.
4.1.2 Raw material
a. The raw material for threaded fasteners shall be selected in accordance
with the metallic materials requirements as per ECSS-Q-ST-70-71C, if not
otherwise specified in the customer specification document for threaded
fasteners.
b. Nut material shall be more ductile than bolt material.
NOTE The reason is that during tightening nut threads
can deflect to seat on the bolt threads.
c. Materials for threaded fasteners shall be selected in order to avoid galling
of the mating surfaces.
NOTE Galling in stainless steel fasteners can be prevented
by using two different steels on the mating
surfaces and by specific surface treatments.
d. Materials for threaded fasteners shall be corrosion resistant
e. Materials shall possess high resistance to stress-corrosion cracking as
specified in ECSS-Q-ST-70-36C.
4.1.3 Head forming
a. Fastener heads shall be formed by hot or cold forging before heat
treating.
NOTE Driving recesses and lightening holes in double
hexagon design can be forged or machined.
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4.1.4 Heat treatment
a. Headed forged blanks shall be heat treated and cold worked by rolling or
drawing methods in accordance with the customer specification
document for threaded fasteners and the specifications in clause 4.2 of
this Standard.
b. Forged blanks belonging to the same batch shall be heat treated in one
batch.
c. The manufacturer shall re-treat a batch which, tested as in 4.3.3, did not
meet the mechanical property requirements, no more than twice (three
times for Titanium alloys).
d. If a different supplier produces the blanks, inspections and quality
control shall be performed as specified in 4.4.2.1 under direct
responsibility of the original blanks’ supplier.
NOTE This is done in the case where the manufacturer is
unable to carry out the blank fabrication as
requested by the customer.
e. Grinding of shank and head bearing surfaces of blanks to obtain
roughness values as specified in 4.2.4 shall be carried out after any heat
treatment.
4.1.5 Head-to-shank fillet rolling
a. Head-to-shank fillet rolling shall be carried out after any heat treatment
and machining processes.
b. Cold rolling shall remove from the fillet surface any evidence of previous
machining or etching process.
c. Geometrical distortion of the fillet surface shall be within the limits
specified in 4.2.3.
NOTE In fasteners having compound radii between head
and shank, cold rolling can be extended to the
remaining part of the fillet surface.
d. There shall be no machining or etching of the fillet radius after rolling.
4.1.6 Threads
a. External threads shall be formed by rolling process.
b. Thread rolling shall be carried out on each fastener in one single
continuous operation.
c. When thread rolling on each fastener is not performed in one single
continuous operation, the threaded fasteners shall be submitted to a
fatigue test in accordance with 4.3.5.
d. No evidence of machining shall be observed on the thread surface after
rolling.
NOTE This applies for fasteners of large diameter, where
threads can be machined oversized and
subsequently rolled.
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e. Thread rolling shall be carried out after heat treatment and machining of
fasteners.
f. Unless otherwise specified in the customer specification document for
threaded fasteners, a single right-hand thread shall be obtained.
g. The thread run-out portion of a bolt or stud shall consist in a progressive
and regular junction with the shank avoiding sharp changes in section.
h. Thread lead and runout portions shall conform to the requirements in
clause 4 of ISO 3353-1:2002.
4.1.7 Identification marking
a. Fasteners shall be marked by depressed characters only with character
size in accordance with the customer specification document for threaded
fasteners and drawings.
b. Characters for marking fasteners shall:
1. be depressed no more than 0,25 mm from the surface;
2. have rounded root form;
3. be impressed on the upper surface of the fastener head.
c. Marks shall univocally identify the fastener batch and manufacturer.
d. Safe-life fasteners shall be identification marked separately after
non-destructive inspection.
4.1.8 Surface treatment
a. In surface plated fasteners, surface plating shall be applied to the entire
fastener surface including the threaded portion.
NOTE Surface plating can cause tolerance variations.
b. Silver plating shall not be used on titanium alloy fasteners.
NOTE Silver and cadmium plating are not used because
they can cause embrittlement of titanium alloys, as
per requirement in ECSS-Q-ST-70-71C.
c. Baking shall be carried out after plating.
NOTE The reason is to prevent hydrogen embrittlement
since electrolytic plating processes generate
hydrogen.
d. The baking temperature shall be selected such that the plating and
substrate materials are not deteriorated
4.1.9 Workmanship, handling and packaging
a. Fasteners shall be free from burrs, tool marks, scale, other surface defects
and contaminants.
b. Fasteners shall be handled and packed during storage and transportation
in the following way:
1. pack fasteners of the same batch in unit packages;
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2. do not apply any protective lubricants or substances on fasteners
unless otherwise specified in the customer specification document
for threaded fasteners.
NOTE This is to prevent mechanical damage and
contamination (e.g. from PVC or fibreboard).
c. Each individual package shall be univocally identified by a durable and
legible external marking indicating the product denomination, quantity,
batch identification, manufacturer, product conformance report as in
4.4.2.5 and date of packing.
d. Fasteners for safe-life applications shall be packed and stored separately.
4.2 Dimensional and metallurgical requirements
4.2.1 General
a. Dimensional and metallurgical controls shall be carried out in accordance
with the sampling procedures and acceptance criteria specified in 4.4.2.1.
b. Designation of dimensions and symbols shall be in accordance with
ISO 225.
c. Dimensional control of fasteners (bolts, nuts and studs) shall be carried
out at room temperature (22 ± 3) °C.
d. Gauges and measuring devices shall be in accordance with ISO 1502.
4.2.2 Nominal dimensions
a. Nominal dimensions shall be in accordance with the detail drawings of
the customer specification document for threaded fasteners.
b. All dimensions shall refer to the final product and include any
dimensional modification subsequent to chemically applied or
electroplated coating.
c. ISO 1502 standards on thread geometry and dimensions shall apply.
d. Tolerances for fasteners shall be in accordance with national or
international aerospace standards (e.g. LN, DIN aerospace standards) or
meet or exceed tolerance values specified in ISO 4759-1 for “Product
grade A”.
4.2.3 Head-to-shank fillet
a. The value of distortion shall not exceed 0,03 mm above and below the
profile lines at points A and B in Figure 4-1.
NOTE In bolts, cold rolling of head-to-shank fillets can
cause distortion of fillet areas. Figure 4-1 shows the
typical distortion of the head-to-shank fillet profile.
b. The value of the extension C of the distorted area in Figure 4-1 shall not
exceed the values indicated in Table 4-1.
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4.2.4 Non-destructive inspections
a. Fasteners shall be free from surface defects such as flaws and inclusions.
b. Inspections on bolts, studs and screws shall be carried out by using liquid
penetrant or magnetic particles in accordance with ASTM E 1417-05e1
and ASTM E 1444-05, respectively.
c. Non-destructive inspections shall be carried out by qualified personnel.
d. Fasteners for safe-life applications shall be inspected as follows:
1. using a 100 % batch inspection plan;
2. by X-ray, ultrasonic or eddy current inspection methods to obtain
95 % (minimum) confidence level and 90 % (minimum) probability
of defect detection.
e. For fasteners for safe-life applications the results of NDI shall be
evaluated in accordance with clause 10.3 of ECSS-E-ST-30-01C.
f. Fasteners with detected surface defects shall be visually re-examined at
×15 (minimum) magnification factor.
NOTE An accurate measurement of the defect size can be
obtained by metallographic examination in
accordance with 4.2.5.
g. The following fasteners shall be declared as nonconformant:
1. fasteners for fail-safe applications if the size of any defect is larger
than the size specified in ISO 6157-2 and ISO 6157-3;
2. fasteners for safe-life applications if the size of any defect is larger
than the size specified in clause 10.3 of ECSS-E-ST-30-01C.
A
A
B
B
C
A
C
C
A
C
Figure 4-1: Tolerance of head-to-shank fillet profile
Table 4-1: Maximum allowed values of the extension C of the
distorted area shown in Figure 4-1
Nominal diameter, d (mm) d < 5 5 ≤ d ≤ 7 8 ≤ d ≤ 10 11 ≤ d ≤ 16 17 ≤ d ≤ 24 d > 24
C maximum (mm) 1,00 1,5 2,5 3,5 4,5 5,0
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4.2.5 Metallurgical examination
a. Fasteners selected for metallurgical examination shall be cut and
prepared for observation in accordance with state-of-the-art standard
laboratory practice.
NOTE Figure 4-2 shows the locations of microsections.
b. Fasteners when visually examined at a magnification of between ×10 and
×50 shall exhibit a continuous grain flow in the head area and
head-to-shank transition zone.
c. Z values shall be equal to or less than the maximum fillet radius
R (Z ≤ Rmax) as specified in the detail drawings of the customer
specification document for threaded fasteners.
NOTE Interruptions in grain flow within the area are
defined by Z dimensions in Figure 4-3.
d. Fasteners when visually examined at a magnification of ×50 shall exhibit
continuous grain flow following the thread profile with maximum
density of flow lines at thread roots.
NOTE For details see Figure 4-4.
e. Fastener microstructure shall be visually inspected for internal defects at
a magnification of ×100 or higher in un-etched condition.
f. Fastener microstructure shall be free from internal defects.
NOTE Internal defects are voids, cracks, inclusions, gross
alloy segregation and indication of overheating.
g. Surface coated or plated fasteners shall exhibit adequate thic
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SLOVENSKI STANDARD
kSIST FprEN 16602-70-46:2014
01-julij-2014
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Space product assurance - Requirements for manufacturing and procurement of
threaded fasteners
Raumfahrtproduktsicherung - Anforderungen für die Herstellung und Beschaffung von
eingezogenen Klemmen/Befestigern
Assurance produit des projets spatiaux - Exigences pour la fabrication et
l'approvisionnement de fixations filetées
Ta slovenski standard je istoveten z: FprEN 16602-70-46
ICS:
49.030.01 Vezni elementi na splošno Fasteners in general
49.140 Vesoljski sistemi in operacije Space systems and
operations
kSIST FprEN 16602-70-46:2014 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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kSIST FprEN 16602-70-46:2014
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kSIST FprEN 16602-70-46:2014
EUROPEAN STANDARD
FINAL DRAFT
FprEN 16602-70-46
NORME EUROPÉENNE
EUROPÄISCHE NORM
April 2014
ICS
English version
Space product assurance - Requirements for manufacturing and
procurement of threaded fasteners
Assurance produit des projets spatiaux - Exigences pour la Raumfahrtproduktsicherung - Anforderungen für die
fabrication et l'approvisionnement de fixations filetées Herstellung und Beschaffung von eingezogenen
Klemmen/Befestigern
This draft European Standard is submitted to CEN members for unique acceptance procedure. It has been drawn up by the Technical
Committee CEN/CLC/TC 5.
If this draft becomes a European Standard, CEN and CENELEC 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.
This draft European Standard was established by CEN and CENELEC in three official versions (English, French, German). A version in any
other language made by translation under the responsibility of a CEN and CENELEC member into its own language and notified to the
CEN-CENELEC Management Centre has the same status as the official versions.
CEN and CENELEC members are the national standards bodies and national electrotechnical committees 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, Slovakia,
Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom.
Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are aware and to
provide supporting documentation.
Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without notice and
shall not be referred to as a European Standard.
CEN-CENELEC Management Centre:
Avenue Marnix 17, B-1000 Brussels
© 2014 CEN/CENELEC All rights of exploitation in any form and by any means reserved Ref. No. FprEN 16602-70-46:2014 E
worldwide for CEN national Members and for CENELEC
Members.
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Table of contents
Foreword . 4
1 Scope . 5
2 Normative references . 6
3 Terms, definitions and abbreviated terms . 8
3.1 Terms defined in other standards . 8
3.2 Terms specific to the present standard . 8
3.3 Abbreviated terms. 9
4 Requirements . 10
4.1 Fabrication . 10
4.1.1 General . 10
4.1.2 Raw material . 10
4.1.3 Head forming . 10
4.1.4 Heat treatment . 11
4.1.5 Head-to-shank fillet rolling . 11
4.1.6 Threads . 11
4.1.7 Identification marking . 12
4.1.8 Surface treatment . 12
4.1.9 Workmanship, handling and packaging . 12
4.2 Dimensional and metallurgical requirements. 13
4.2.1 General . 13
4.2.2 Nominal dimensions . 13
4.2.3 Head-to-shank fillet . 13
4.2.4 Non-destructive inspections . 14
4.2.5 Metallurgical examination . 15
4.2.6 Measurement of hydrogen content . 16
4.2.7 Outgassing and offgassing . 16
4.3 Mechanical testing . 17
4.3.1 General . 17
4.3.2 Hardness test . 17
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4.3.3 Tensile test . 18
4.3.4 Shear test . 19
4.3.5 Fatigue test . 20
4.3.6 Creep test . 20
4.3.7 Corrosion test . 22
4.3.8 Stress-corrosion test . 22
4.4 Quality assurance . 23
4.4.1 General . 23
4.4.2 Quality requirements . 23
Annex A (normative) Customer specification document for threaded
fasteners – DRD . 26
Annex B (normative) Product conformance report (PCR) – DRD . 28
Annex C (informative) Inspection levels, acceptance quality limits (AQL)
and limiting quality levels (LQ) for inspection of fasteners . 30
Bibliography . 32
Figures
Figure 4-1: Tolerance of head-to-shank fillet profile . 14
Figure 4-2: Location of microsections for metallurgical examination . 15
Figure 4-3: Area delimiting interruptions in grain flow in the head-to-shank region . 16
Figure 4-4: Example of a regular grain flow in a threaded surface . 16
Figure 4-5: Locations for hardness testing (indicated with cross symbol) . 18
Figure 4-6: Loading schematic for tensile testing of threaded fasteners . 21
Figure 4-7: Schematic of an example of double-shear loading jigs . 22
Tables
Table 4-1: Maximum allowed values of the extension C of the distorted area shown in
Figure 4-1 . 14
Table C- 1: Inspection levels, acceptance quality limits (AQL) and limiting quality levels
(LQ) for inspection of fasteners . 30
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Foreword
This document (FprEN 16602-70-46:2014) has been prepared by Technical
Committee CEN/CLC/TC 5 “Space”, the secretariat of which is held by DIN
(Germany).
This document (FprEN 16602-70-46:2014) originates from ECSS-Q-ST-70-46C
Rev.1.
This document is currently submitted to the Unique Acceptance Procedure.
This document has been developed to cover specifically space systems and will
the-refore have precedence over any EN covering the same scope but with a
wider do-main of applicability (e.g. : aerospace).
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1
Scope
This Standard defines the requirements for manufacturing, provision,
inspection and quality control of high-quality threaded fastening devices (bolts,
nuts, studs and screws) hereafter referred to as threaded fasteners or fasteners,
used in space hardware.
This Standard does not include a complete review of the factors relevant to the
fabrication of high quality threaded fasteners. It provides the definition of the
technical requirements and quality control procedures to be applied in the
fabrication and supply of threaded fasteners for spacecraft applications.
Fasteners for spacecraft applications are those aerospace standard fasteners (i.e.
in accordance with LN, DIN or other national or international aerospace
standards), or those fasteners meeting or exceeding the requirements in
ISO 4759-1 for “Product grade A”, which also fulfil the requirements for space
applications as specified in the present document.
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2
Normative references
The following dated normative documents are called by the requirements of
this ECSS Standard and therefore constitute requirements to it. Subsequent
amendments to, or revisions of any of these publications do not apply.
NOTE However, parties to agreements based on this
ECSS Standard are encouraged to investigate the
possibility of applying the most recent editions of
the normative documents indicated below.
EN reference Reference in text Title
EN 16601-00-01 ECSS-S-ST-00-01C ECSS system – Glossary of terms
EN 16603-30-01 ECSS-E-ST-30-01C Space engineering — Fracture control
EN 16602-70 ECSS-Q-ST-70C Space product assurance — Materials, parts and
processes
EN 16602-70-02 ECSS-Q-ST-70-02C Space product assurance — Thermal vacuum
outgassing test for the screening of space materials
EN 16602-70-29 ECSS-Q-ST-70-29C Space product assurance — The determination of
offgassing products from materials and assembled
articles to be used in a manned space vehicle crew
compartment
EN 16602-70-36 ECSS-Q-ST-70-36C Space product assurance — Material selection for
controlling stress-corrosion cracking
EN 16602-70-37 ECSS-Q-ST-70-37C Space product assurance — Determination of the
susceptibility of metals to stress— corrosion cracking
EN 16602-70-71 ECSS-Q-ST-70-71C Space product assurance — Data for selection of
space materials
ISO 204 Metallic materials — Uninterrupted uniaxial creep
testing in tension — Method of test
ISO 225 Fasteners — Bolts, screws, studs and nuts — Symbols
and designations of dimensions
ISO 1502 ISO general — purpose metric screw threads —
Gauges and gauging
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EN reference Reference in text Title
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 2859-2 Sampling procedures for inspection by attributes,
Part 2: Sampling plans indexed by limiting quality
(LQ), for isolated lots inspection
ISO 3353-1:2002 Aerospace — Lead and runout threads — Part 1:
Rolled external threads
ISO 3800 Threaded fasteners – Axial load fatigue testing – Test
methods and evaluation of results
ISO 4759-1 Tolerances for fasteners — Part 1: Bolts, screws, studs
and nuts — Product grades A, B and C
ISO 6157-2 Fasteners — Surface discontinuities – Part 2: Nuts
ISO 6157-3 Fasteners – Surface discontinuities – Part 3: Bolts,
screws and studs for special requirements
ISO 6506-1 Metallic materials — Brinell hardness test — Part 1:
Test method
ISO 6506-2 Metallic materials — Brinell hardness test — Part 2:
Verification and calibration of testing machines
ISO 6506-3 Metallic materials — Brinell hardness test — Part 3:
Calibration of reference blocks
ISO 6507-1 Metallic materials — Vickers hardness test – Part 1:
Test method
ISO 6507-2 Metallic materials — Vickers hardness test — Part 2:
Verification and calibration of testing machines
ISO 6507-3 Metallic materials — Vickers hardness test — Part 3:
Calibration of reference blocks
ISO 6508-1 Metallic materials — Rockwell hardness test — Part
1: Test method
ISO 6508-2 Metallic materials — Rockwell hardness test — Part
2: Verification and calibration of testing machines
ISO 6508-3 Metallic materials — Rockwell hardness test — Part
3: Calibration of reference blocks
ISO 9140 Aerospace – Nuts, plain or slotted (castellated) – Test
methods
DIN ISO 9152 Aerospace – Bolts, with MJ Threads, in Titanium
alloys, strength class 1100 MPa – Procurement
specification
ASTM B 117-07a Standard practice for operating salt spray (fog)
apparatus
ASTM E 1417-05e1 Standard practice for liquid penetrant testing
ASTM E 1444-05 Standard practice for magnetic particle testing
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3
Terms, definitions and abbreviated terms
3.1 Terms defined in other standards
For the purpose of this Standard, the terms and definitions from ECSS-S-ST-00-01
and ECSS-Q-ST-70 apply.
3.2 Terms specific to the present standard
3.2.1 bolt
cylindrical screwed bar provided with a head, generally not threaded along its
entire length
NOTE For example: Shank plus threaded portion.
3.2.2 fail-safe
approach in which the structure is designed with sufficient structural
redundancy to ensure that the failure of one structural element does not cause
general failure of the entire structure
3.2.3 fastener
device used to hold parts firmly together in an assembly
3.2.4 galling
condition whereby excessive friction between high spots results in localized
welding with subsequent splitting and a further roughening of rubbing surfaces
of one or both or two mating parts
3.2.5 nut
metal collar, screwed internally, to fit a bolt
NOTE Usually hexagonal in shape and operated by a
spanner.
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3.2.6 safe-life
approach which requires that the largest undetected defect that can exist in the
structure does not grow to failure when subjected to loads and environments
encountered in service
3.2.7 sampling plan
combination of sample size to be used with associated batch acceptability
criteria
3.2.8 shank
unthreaded portion of the cylindrical screwed bar of a bolt
3.2.9 stud
shank, or endless bolt, externally screwed from one end, both ends or along its
entire length
3.2.10 (screw) thread
helical ridge of approximately triangular, square or rounded section, formed on
a cylindrical core, the pitch and core diameter being standardised under various
systems
3.2.11 threaded fastener
device composed by a cylindrical screwed bar provided with a head and a
metal collar, screwed internally, to fit the cylindrical bar that is used to hold
parts firmly together in an assembly
3.3 Abbreviated terms
For the purpose of this Standard, the abbreviated terms from ECSS-S-ST-00-01C
and the following apply:
Abbreviation Meaning
AQL acceptance quality level
ASTM American Society for Testing and Materials
HB Brinell hardness
HRC Rockwell hardness
HV Vickers hardness
ISO International Organization for Standardization
LQ limiting quality
PCR product conformance report
PVC polyvinyl chloride
RMC raw material certificate
UTS ultimate tensile strength
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4
Requirements
4.1 Fabrication
4.1.1 General
a. The customer shall establish a specification document in conformance
with the DRD in Annex A.
b. The manufacturer shall have a quality assurance system.
c. The manufacturer shall verify and assure conformance during
production to the technical requirements specified in this clause.
4.1.2 Raw material
a. The raw material for threaded fasteners shall be selected in accordance
with the metallic materials requirements as per ECSS-Q-ST-70-71C, if not
otherwise specified in the customer specification document for threaded
fasteners.
b. Nut material shall be more ductile than bolt material.
NOTE The reason is that during tightening nut threads
can deflect to seat on the bolt threads.
c. Materials for threaded fasteners shall be selected in order to avoid galling
of the mating surfaces.
NOTE Galling in stainless steel fasteners can be prevented
by using two different steels on the mating
surfaces and by specific surface treatments.
d. Materials for threaded fasteners shall be corrosion resistant
e. Materials shall possess high resistance to stress-corrosion cracking as
specified in ECSS-Q-ST-70-36C.
4.1.3 Head forming
a. Fastener heads shall be formed by hot or cold forging before heat
treating.
NOTE Driving recesses and lightening holes in double
hexagon design can be forged or machined.
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4.1.4 Heat treatment
a. Headed forged blanks shall be heat treated and cold worked by rolling or
drawing methods in accordance with the customer specification
document for threaded fasteners and the specifications in clause 4.2 of
this Standard.
b. Forged blanks belonging to the same batch shall be heat treated in one
batch.
c. The manufacturer shall re-treat a batch which, tested as in 4.3.3, did not
meet the mechanical property requirements, no more than twice (three
times for Titanium alloys).
d. If a different supplier produces the blanks, inspections and quality
control shall be performed as specified in 4.4.2.1 under direct
responsibility of the original blanks’ supplier.
NOTE This is done in the case where the manufacturer is
unable to carry out the blank fabrication as
requested by the customer.
e. Grinding of shank and head bearing surfaces of blanks to obtain
roughness values as specified in 4.2.4 shall be carried out after any heat
treatment.
4.1.5 Head-to-shank fillet rolling
a. Head-to-shank fillet rolling shall be carried out after any heat treatment
and machining processes.
b. Cold rolling shall remove from the fillet surface any evidence of previous
machining or etching process.
c. Geometrical distortion of the fillet surface shall be within the limits
specified in 4.2.3.
NOTE In fasteners having compound radii between head
and shank, cold rolling can be extended to the
remaining part of the fillet surface.
d. There shall be no machining or etching of the fillet radius after rolling.
4.1.6 Threads
a. External threads shall be formed by rolling process.
b. Thread rolling shall be carried out on each fastener in one single
continuous operation.
c. When thread rolling on each fastener is not performed in one single
continuous operation, the threaded fasteners shall be submitted to a
fatigue test in accordance with 4.3.5.
d. No evidence of machining shall be observed on the thread surface after
rolling.
NOTE This applies for fasteners of large diameter, where
threads can be machined oversized and
subsequently rolled.
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e. Thread rolling shall be carried out after heat treatment and machining of
fasteners.
f. Unless otherwise specified in the customer specification document for
threaded fasteners, a single right-hand thread shall be obtained.
g. The thread run-out portion of a bolt or stud shall consist in a progressive
and regular junction with the shank avoiding sharp changes in section.
h. Thread lead and runout portions shall conform to the requirements in
clause 4 of ISO 3353-1:2002.
4.1.7 Identification marking
a. Fasteners shall be marked by depressed characters only with character
size in accordance with the customer specification document for threaded
fasteners and drawings.
b. Characters for marking fasteners shall:
1. be depressed no more than 0,25 mm from the surface;
2. have rounded root form;
3. be impressed on the upper surface of the fastener head.
c. Marks shall univocally identify the fastener batch and manufacturer.
d. Safe-life fasteners shall be identification marked separately after
non-destructive inspection.
4.1.8 Surface treatment
a. In surface plated fasteners, surface plating shall be applied to the entire
fastener surface including the threaded portion.
NOTE Surface plating can cause tolerance variations.
b. Silver plating shall not be used on titanium alloy fasteners.
NOTE Silver and cadmium plating are not used because
they can cause embrittlement of titanium alloys, as
per requirement in ECSS-Q-ST-70-71C.
c. Baking shall be carried out after plating.
NOTE The reason is to prevent hydrogen embrittlement
since electrolytic plating processes generate
hydrogen.
d. The baking temperature shall be selected such that the plating and
substrate materials are not deteriorated
4.1.9 Workmanship, handling and packaging
a. Fasteners shall be free from burrs, tool marks, scale, other surface defects
and contaminants.
b. Fasteners shall be handled and packed during storage and transportation
in the following way:
1. pack fasteners of the same batch in unit packages;
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2. do not apply any protective lubricants or substances on fasteners
unless otherwise specified in the customer specification document
for threaded fasteners.
NOTE This is to prevent mechanical damage and
contamination (e.g. from PVC or fibreboard).
c. Each individual package shall be univocally identified by a durable and
legible external marking indicating the product denomination, quantity,
batch identification, manufacturer, product conformance report as in
4.4.2.5 and date of packing.
d. Fasteners for safe-life applications shall be packed and stored separately.
4.2 Dimensional and metallurgical requirements
4.2.1 General
a. Dimensional and metallurgical controls shall be carried out in accordance
with the sampling procedures and acceptance criteria specified in 4.4.2.1.
b. Designation of dimensions and symbols shall be in accordance with
ISO 225.
c. Dimensional control of fasteners (bolts, nuts and studs) shall be carried
out at room temperature (22 ± 3) °C.
d. Gauges and measuring devices shall be in accordance with ISO 1502.
4.2.2 Nominal dimensions
a. Nominal dimensions shall be in accordance with the detail drawings of
the customer specification document for threaded fasteners.
b. All dimensions shall refer to the final product and include any
dimensional modification subsequent to chemically applied or
electroplated coating.
c. ISO 1502 standards on thread geometry and dimensions shall apply.
d. Tolerances for fasteners shall be in accordance with national or
international aerospace standards (e.g. LN, DIN aerospace standards) or
meet or exceed tolerance values specified in ISO 4759-1 for “Product
grade A”.
4.2.3 Head-to-shank fillet
a. The value of distortion shall not exceed 0,03 mm above and below the
profile lines at points A and B in Figure 4-1.
NOTE In bolts, cold rolling of head-to-shank fillets can
cause distortion of fillet areas. Figure 4-1 shows the
typical distortion of the head-to-shank fillet profile.
b. The value of the extension C of the distorted area in Figure 4-1 shall not
exceed the values indicated in Table 4-1.
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4.2.4 Non-destructive inspections
a. Fasteners shall be free from surface defects such as flaws and inclusions.
b. Inspections on bolts, studs and screws shall be carried out by using liquid
penetrant or magnetic particles in accordance with ASTM E 1417-05e1
and ASTM E 1444-05, respectively.
c. Non-destructive inspections shall be carried out by qualified personnel.
d. Fasteners for safe-life applications shall be inspected as follows:
1. using a 100 % batch inspection plan;
2. by X-ray, ultrasonic or eddy current inspection methods to obtain
95 % (minimum) confidence level and 90 % (minimum) probability
of defect detection.
e. For fasteners for safe-life applications the results of NDI shall be
evaluated in accordance with clause 10.3 of ECSS-E-ST-30-01C.
f. Fasteners with detected surface defects shall be visually re-examined at
×15 (minimum) magnification factor.
NOTE An accurate measurement of the defect size can be
obtained by metallographic examination in
accordance with 4.2.5.
g. The following fasteners shall be declared as nonconformant:
1. fasteners for fail-safe applications if the size of any defect is larger
than the size specified in ISO 6157-2 and ISO 6157-3;
2. fasteners for safe-life applications if the size of any defect is larger
than the size specified in clause 10.3 of ECSS-E-ST-30-01C.
A
A
B
B
C
A
C
C
A
C
Figure 4-1: Tolerance of head-to-shank fillet profile
Table 4-1: Maximum allowed values of the extension C of the
distorted area shown in Figure 4-1
Nominal diameter, d (mm) d < 5 5 ≤ d ≤ 7 8 ≤ d ≤ 10 11 ≤ d ≤ 16 17 ≤ d ≤ 24 d > 24
C maximum (mm) 1,00 1,5 2,5 3,5 4,5 5,0
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4.2.5 Metallurgical examination
a. Fasteners selected for metallurgical examination shall be cut and
prepared for observation in accordance with state-of-the-art standard
laboratory practice.
NOTE Figure 4-2 shows the locations of microsections.
b. Fasteners when visually examined at a magnification of between ×10 and
×50 shall exhibit a continuous grain flow in the head area and
head-to-shank transition zone.
c. Z values shall be equal to or less than the maximum fillet radius
R (Z ≤ Rmax) as specified in the detail drawings of the customer
specification document for threaded fasteners.
NOTE Interruptions in grain flow within the area are
defined by Z dimensions in Figure 4-3.
d. Fasteners when visually examined at a magnification of ×50 shall exhibit
continuous grain flow following the thread profile with maximum
density of flow lines at thread roots.
NOTE For details see Figure 4-4.
e. Fastener microstructure shall be visually inspected for internal defects at
a magnification of ×100 or higher in un-etched condition.
f. Fastener microstructure shall be free from internal defects.
NOTE Internal defects are voids, cracks, inclusions, gross
alloy segregation and indication of overheating.
g. Surface coated or plated fasteners shall exhibit adequate thickness,
uniformity and integrity of the protective layer.
h. For fasteners in Titanium alloy strength class 1100 MPa, DIN ISO 9152
shall apply.
A
B
C
A B C
d
d/2* d/2*
(*) minimum required
Figure 4-2: Location of microsections for metallurgical examination
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Z
Z
Z
Z
Figure 4-3: Area delimiting interruptions in grain flow in the head-to-shank region
Figure 4-4:
...
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