kSIST FprEN 6128:2026

• Abstract:

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

• Status: Not Published
• Public Enquiry End Date: 15-Oct-2024
• ICS: 49.030.20 - Bolts, screws, studs
• Technical Committee: I13 - Imaginarni 13
• Current Stage: 5020 - Formal vote (FV) (Adopted Project)
• Start Date: 06-Aug-2026
• Due Date: 24-Sep-2026
• Completion Date: 07-Aug-2026
• Ref Project: FprEN 6128 - Aerospace series - Blind bolt, 100° flush head, high strength

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

Overview

kSIST FprEN 6128:2026 is an advanced standard developed by SIST, focusing on aerospace fasteners-specifically, stainless steel blind bolts with a 100° flush head and high strength. This European Standard outlines the configuration, dimensions, tolerances, and mass of these bolts, ensuring consistency and reliability for aerospace applications where flush-fitting, high-strength solutions are critical.

The document supersedes EN 6128:2017, reflecting updated requirements and specifications. Developed by the ASD-STAN technical committee and subject to CEN enquiry, this standard helps manufacturers and users meet the rigorous demands of the aerospace sector.

Key Topics

• Bolt Configuration and Geometry
  Defines the precise dimensions, head angle, and flush surface requirements for the blind bolt, ensuring proper installation and aerodynamics.
• Material and Finish
  Specifies the use of corrosion-resistant stainless steel alloys (A-286 CRES, 316 CRES, Inconel) and details on surface treatment, passivation per SAE standards, and optional lubricant coatings.
• Strength and Performance
  Establishes minimum requirements for static strength, tensile preload, shear, and spindle retention-essential for structural integrity in flight operations.
• Grip Range and Mass
  Provides standard measurement codes for grip lengths and associated mass, ensuring accurate selection for various assembly needs.
• Marking and Designation
  Stipulates identification requirements according to EN 2424, allowing for traceability and standardized part referencing.

Applications

The kSIST FprEN 6128 standard is crucial for organizations operating in the aerospace sector, including:

• Aircraft and Spacecraft Assembly
  Blind bolts with 100° flush heads are ideal for panels and structural components where access is limited to one side and a smooth outer surface is essential for aerodynamic performance.
• Maintenance and Repair Operations (MRO)
  Standardized blind bolts support efficient fastener replacement, part traceability, and compliance with quality control procedures.
• OEM Manufacturing
  Aerospace OEMs benefit from standardized bolt specifications for consistency across large production runs, facilitating regulatory compliance, and reducing procurement complexity.
• Component Suppliers
  Suppliers can ensure their products meet the stringent material and performance criteria demanded in aerospace, improving product acceptance across a global supply chain.

Related Standards

Manufacturers and engineers working with kSIST FprEN 6128:2026 may also reference several related standards to ensure comprehensive compliance and interoperability:

• EN 2424: Aerospace series-Marking of aerospace products
• EN 4473: Technical specification for aluminium-pigmented coatings for fasteners
• SAE AMS2700, SAE AMS5737, SAE AMS5690, SAE AMS5687: Standards for passivation and material properties of stainless and nickel alloys
• MIL-PRF-46010, SAE AS5272, DOD-L-85645: Specifications for recommended dry film and solid-film lubricants
• NASM8975: General technical requirements for high-strength, installation formed aerospace fasteners

---

kSIST FprEN 6128:2026 provides aerospace professionals with reliable, standardized criteria for the selection and use of high-strength blind bolts, supporting flight safety, aerodynamic efficiency, and robust assembly practices. By adhering to this standard, aerospace manufacturers and assemblers can achieve improved product performance, streamlined maintenance, and assured compliance with European and global requirements.

SLOVENSKI STANDARD
oSIST prEN 6128:2024
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
oSIST prEN 6128:2024 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

oSIST prEN 6128:2024
oSIST prEN 6128:2024
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.

oSIST prEN 6128:2024
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
oSIST prEN 6128:2024
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.
oSIST prEN 6128:2024
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/.
oSIST prEN 6128:2024
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
oSIST prEN 6128:2024
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
oSIST prEN 6128:2024
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)
oSIST prEN 6128:2024
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 ±
...