FprEN 6128

Aerospace series - Blind bolt, 100° flush head, high strength

This document specifies the configuration, dimensions, tolerances and mass of a stainless steel blind bolt with 100° flush head for aerospace application.

Luft- und Raumfahrt - Blindbolzen, 100° Senkkopf, hochfest

Série aérospatiale - Boulon aveugle, tête fraisée 100°, haute résistance

Le présent document spécifie la configuration, les dimensions, les tolérances et la masse d’un boulon aveugle en acier inoxydable, à tête fraisée 100°, pour les applications aérospatiales.

Aeronavtika - Slepa kovica, 100° ugrezna glava, visoka trdnost

General Information

• Status: Not Published
• Publication Date: 03-Jan-2027
• ICS: 49.030.20 - Bolts, screws, studs
• Technical Committee: ASD-STAN - Aerospace
• Drafting Committee: ASD-STAN/D 3/S 2 - Fasteners
• Current Stage: 4599 - Dispatch of FV draft to CMC - Finalization for Vote
• Start Date: 29-May-2026
• Completion Date: 29-May-2026
• Ref Project: oSIST prEN 6128:2024 - Aerospace series - Blind bolt, 100° flush head, high strength

Relations

• Revises: EN 6128:2017 - Aerospace series - Blind bolt, 100° flush head, high strength
• Effective Date: 06-Sep-2023

Overview

FprEN 6128 is a draft European Standard developed by CEN as part of the aerospace series. It provides comprehensive specifications for high strength, 100° flush head blind bolts made from stainless steel. These fasteners are crucial in aerospace applications, where structural integrity, precise fit, and high performance are essential. The standard outlines requirements for configuration, dimensions, tolerances, mass, materials, finishes, and lubrication of these specialized blind bolts.

Key Topics

• Configuration & Dimensions
  The standard specifies the geometry and dimensional requirements for 100° flush head blind bolts, ensuring compatibility and consistent performance within aerospace assemblies.

• Strength & Preload
  Blind bolts covered under FprEN 6128 must meet defined static strength, tensile preload, and spindle retention properties, making them suitable for demanding aerospace environments.

• Material & Finish
  Standardized materials, mainly stainless steels (A-286 CRES, 316 CRES) and Inconel, are designated according to international specifications. Permitted finishes include passivation and aluminium pigmented coatings, which enhance corrosion resistance and durability.

• Lubrication Options
  Acceptance of various aerospace-approved lubricants ensures proper installation and operational life, aligning with aviation industry specifications.

• Designation & Identification
  FprEN 6128 standardizes the method for identifying and marking the fasteners, supporting traceability and ensuring correct installation.

Applications

FprEN 6128 is utilized across a range of aerospace applications, with practical value in:

• Aircraft Structural Assembly
  The 100° flush head blind bolts are vital for joining structural components where access is limited to one side, supporting streamlined assembly and maintenance without compromising aerodynamics or strength.

• Retrofit & Repair
  Their blind nature allows for quick and reliable repairs in the field, minimizing aircraft downtime and maintaining safety standards while conforming to international norms.

• Spacecraft and Defense Systems
  The standardized high-strength properties ensure suitability for airframe construction, satellites, and defense platforms where integrity under load and environmental resistance are crucial.

• OEM and Aftermarket Fastening
  OEMs and maintenance providers benefit from interchangeability and quality assurance by adhering to FprEN 6128, simplifying inventory and compliance processes.

Related Standards

Several key standards are referenced within FprEN 6128 or complement its scope:

• EN 2424: Aerospace series - Marking of aerospace products
  Specifies marking requirements for traceability and identification.

• EN 4473: Aluminium pigmented coatings for aerospace fasteners
  Technical requirements for corrosion-resistant coatings.

• SAE AMS2700: Passivation of corrosion resistant steels
  Guidelines for chemical treatments enhancing material durability.

• NASM8975: Fastener, Blind, High Strength, Installation Formed
  Covers general specifications for installation-formed high strength blind fasteners.

• MIL-PRF-46010 and SAE AS5272:
  Aerospec-specific lubricants and treatments to ensure optimal performance and corrosion inhibition.

These related aerospace fastener standards help ensure consistency, quality, and safety across multiple tiers of the aerospace supply and manufacturing chain.

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Keywords: FprEN 6128, aerospace blind bolt, 100 degree flush head, high strength fastener, stainless steel bolt, aerospace standard, structural fastener, CEN, aircraft assembly, high strength blind fastener, passivated bolt, aerospace bolt marking, EN 6128.

Standards Content (Sample)

SLOVENSKI STANDARD
01-oktober-2024
Aeronavtika - Slepa kovica, 100° ugrezna glava, visoka trdnost
Aerospace series - Blind bolt, 100° flush head, high strength
Luft- und Raumfahrt - Blindbolzen, 100° Senkkopf, hochfest
Série aérospatiale - Boulon aveugle, tête fraisée 100°, haute résistance
Ta slovenski standard je istoveten z: prEN 6128
ICS:
49.030.20 Sorniki, vijaki, stebelni vijaki Bolts, screws, studs
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

DRAFT
EUROPEAN STANDARD
prEN 6128
NORME EUROPÉENNE
EUROPÄISCHE NORM
July 2024
ICS 49.030.20 Will supersede EN 6128:2017
English Version
Aerospace series - Blind bolt, 100° flush head, high
strength
Série aérospatiale - Boulon aveugle, tête fraisée 100°, Luft- und Raumfahrt - Blindbolzen, 100° Senkkopf,
haute résistance hochfest
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee ASD-
STAN.
If this draft becomes a European Standard, 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.

This draft European Standard was established by CEN 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, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye 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.

EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2024 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 6128:2024 E
worldwide for CEN national Members.

prEN 6128:2024 (E)
Contents Page
European foreword . 3
1 Scope . 4
2 Normative references . 4
3 Terms and definitions . 4
4 Requirements . 5
4.1 Configuration, dimensions tolerances, static strength, preload and spindle retention . 5
4.2 Grip range and mass . 5
4.3 Material, finish, lubrication . 5
5 Designation . 16
6 Marking . 16
7 Technical specification . 16
prEN 6128:2024 (E)
European foreword
This document (prEN 6128:2024) has been prepared by ASD-STAN.
After enquiries and votes carried out in accordance with the rules of this Association, this document has
received the approval of the National Associations and the Official Services of the member countries of
ASD-STAN, prior to its presentation to CEN.
This document is currently submitted to the CEN Enquiry.
This document will supersede EN 6128:2017.
This document includes the following significant technical changes with respect to EN 6128:2017:
a) Figure 1 and Figure 2 updated (dimensions Q and X removed);
b) dimension Q removed in Table 1 accordingly;
c) Table 3: Single values corrected and hole limits removed;
d) Table 4: Values of diameter code 05 corrected;
e) Table 5 and Table 6 updated according updated normative references and preferred options.
prEN 6128:2024 (E)
1 Scope
This document specifies the configuration, dimensions, tolerances and mass of a stainless steel blind
bolt with 100° flush head for aerospace application.
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.
EN 2424, Aerospace series — Marking of aerospace products
EN 4473, Aerospace series — Aluminium pigmented coatings for fasteners — Technical specification
DOD-L-85645, Lubricant, Dry Film, Molecular Bonded
MIL-PRF-46010, Lubricant, Solid Film, Heat Cured, Corrosion Inhibiting NATO Code – S-1738
NASM8975, Fastener, Blind, High Strength, Installation Formed, Cres, Heat Resistant Steel and Titanium,
General Specification for
SAE AMS2700, Passivation of Corrosion Resistant Steels
SAE AMS5687, Nickel Alloy, Corrosion- and Heat-Resistant, Wire 74Ni-15.5Cr-8.0Fe Annealed
SAE AMS5690, Steel, Corrosion and Heat Resistant, Wire 17Cr-12Ni-2.5Mo (316) Solution Heat Treated
SAE AMS5737, Steel, Corrosion- and Heat-Resistant, Bars, Wire, Forgings, Mechanical Tubing, and Stock
for Forging and Heading 15Cr-25.5Ni-1.2Mo-2.1Ti-0.006B-0.30V (A286) Consumable Electrode Remelted
1650 °F (899 °C) Solution and Precipitation Heat Treated
SAE AS5272, Lubricant, Solid Film, Heat Cured, Corrosion Inhibiting, Procurement Specification
SAE AS87132, Lubricant, Cetyl Alcohol, 1-Hexadecanol, Application to Fasteners
3 Terms and definitions
No terms and definitions are listed in this document.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https://www.iso.org/obp/
— IEC Electropedia: available at https://www.electropedia.org/

Published by Department of Defense (DoD), available at: https://assist.dla.mil/.
Published by Aerospace Industries Association (AIA), available at: https://www.aia-aerospace.org/.
Published by Society of Automotive Engineers (SAE), available at: https://www.sae.org/.
prEN 6128:2024 (E)
4 Requirements
4.1 Configuration, dimensions tolerances, static strength, preload and spindle retention
The configuration, dimensions, tolerances, static strength, tensile preload and spindle retention shall
conform to Figure 1, Figure 2 and Table 1 and Table 2.
4.2 Grip range and mass
Grip range and mass shall be according to Table 3 and Table 4.
4.3 Material, finish, lubrication
Material, finish and lubrication shall be according to Table 5 and Table 6.

a) Bolt configuration
prEN 6128:2024 (E)
b) Serrated Pin geometry
Key
1 marking see Clause 6
2 serrated pin
3 locking collar
4 crown height (C)
5 grip
6 sleeve
7 shifting anvil
8 drive washer
a
Diameter of serrated pin head shall not exceed “⌀D” max.
b
steners are supplied with shifting anvil/drive washer of manufacturer’s option. The shifting anvil/drive
washer is not part of the installed fastener.
c
optional configuration
Figure 1 — Configuration — Dimensions
prEN 6128:2024 (E)
Key
1 grip
a
Blind side head may be installed on 7° max. slope; 5° max. slope for diameter codes 10 and 12.
Figure 2 — Typical installation
Table 1 — Dimensions and tolerances
Dimensions in mm (inch)
Diameter code
05 06 08 10 12
Theor.
8,48 9,83 12,90 16,13 19,38
⌀A
(0,334) (0,387) (0,508) (0,635) (0,763)
Ref.
1,88 2,08 2,74 3,56 4,27
B Ref.
(0,074) (0,082) (0,108) (0,140) (0,168)
0,28 0,33 0,43 0,51 0,58
C max.
(0,011) (0,013) (0,017) (0,020) (0,023)
±0,025 4,14 5,03 6,58 7,90 9,47
⌀D
(±0,001) (0,163) (0,198) (0,259) (0,311) (0,373)
±0,127 9,53 9,53 9,53 11,13 12,70
a
⌀J
(±0,005) (0,375) (0,375) (0,375) (0,438) (0,500)
±1,52 3,56 4,06 4,83 3,94 4,95
N
(±0,060) (0,140) (0,160) (0,190) (0,155) (0,195)
3,05 3,81 4,83 5,88 7,06
⌀D max.
(0,120) (0,150) (0,190) (0,231) (0,278)
2,16 2,79 3,66 4,62 5,69
⌀D max.
(0,085) (0,110) (0,144) (0,182) (0,224)
7,193 8,311 10,973 13,846 16,718
7,188 8,306 10,968 13,840 16,713
⌀W Gage dia.
(0,283 2) (0,327 2) (0,432 0) (0,545 1) (0,658 2)
(0,283 0) (0,327 0) (0,431 8) (0,544 9) (0,658 0)
prEN 6128:2024 (E)
Diameter code
05 06 08 10 12
0,523 0,617 0,787 0,932 1,087
0,434 0,521 0,686 0,826 0,965
Gage
H
height
(0,020 6) (0,024 3) (0,031 0) (0,036 7) (0,042 8)
(0,017 1) (0,020 5) (0,027 0) (0,032 5) (0,038 0)
7,62 8,13 9,40 8,89 10,29
b
P max.
(0,300) (0,320) (0,370) (0,350) (0,405)
5,66 6,86 9,01 9,47 11,38
⌀P min.
(0,223) (0,270) (0,355) (0,373) (0,448)
0,25 0,38 0,51 0,64 0,76
R max.
(0,010) (0,015) (0,020) (0,025) (0,030)
5,89 7,42 9,17 8,10 9,25
S max.
(0,232) (0,292) (0,361) (0,319) (0,364)
±0,76 20,32 21,08 24,77 31,60 41,35
J
(±0,030) (0,800) (0,830) (0,975) (1,244) (1,628)
Number
of
J2 18 19 20 18 18
serrations
min.
±0,76 1,52 1,78 2,29 1,98 1,85
X
(±0,030) (0,060) (0,070) (0,090) (0,078) (0,073)
0,13 0,13 0,13 0,36 0,36
E min.
(0,005) (0,005) (0,005) (0,014) (0,014)
0,33 0,33 0,33 0,51 0,58
C Ref.
(0,013) (0,013) (0,013) (0,022) (0,023)
±0,05 0,81 0,81 0,81 1,42 1,70
C
(±0,002) (0,032) (0,032) (0,032) (0,056) (0,067)
F ±5° 45° 45° 45° 45° 45°
G ±5° 30° 30° 30° 30° 30°
a
Diameter code 05 is also available with reduced diameter shifting anvil/drive washer [7,93 mm ±
...