FprEN 6127

• Abstract:

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

• 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: 6055 - CEN Ratification completed (DOR) - Publishing
• Start Date: 25-Oct-2026
• Completion Date: 25-Oct-2026
• Ref Project: kSIST FprEN 6127:2026 - Aerospace series - Blind bolt, 100° reduced flush head, high strength

FprEN 6127 is a CEN draft European Standard for an aerospace series blind bolt, 100° reduced flush head, high strength. It specifies the configuration, dimensions, tolerances, mass, material, finish, lubrication, marking and designation for a stainless steel blind bolt used in aerospace applications. Engineers, quality teams and buyers use it to identify the fastener variant, select the right grip length and oversize, and check performance and traceability.

What does FprEN 6127 specify?

FprEN 6127 defines one blind bolt type and organizes the document into seven clauses: Scope, Normative references, Terms and definitions, Requirements, Designation, Marking and Technical specification.

Clause	What it covers
1	Scope of the stainless steel blind bolt for aerospace use
2	Normative references for marking, materials, coatings, lubricants and general blind fastener requirements
3	Terms and definitions
4	Requirements for geometry, grip range, mass, materials, finish, lubrication and first oversize
5	Designation system
6	Marking on the fastener head
7	Technical specification basis

The scope is narrow and practical: it is for a stainless steel blind bolt with a 100° reduced flush head for aerospace application. In use, that means the document is intended to define a specific fastener family rather than a general bolt range.

What are the key requirements of FprEN 6127?

Geometry, tolerances and performance

Clause 4.1 ties the configuration, dimensions and tolerances to Figure 1, Figure 2, Table 1 and Table 2. In practice, this is the main control point for design and inspection: the part has to match the defined head, serrated pin, sleeve and locking collar geometry, and it also has to meet the stated static strength, tensile preload and spindle retention values.

Figure 2 adds an installation condition that the blind side head may be installed on a slope up to 7° maximum. That matters for assembly planning because the joint geometry can affect how the fastener is seated.

Grip range, mass and oversize version

Clause 4.2 assigns grip range and mass in Table 3 and Table 4. This is what users rely on when matching the fastener to joint thickness and when comparing part weight across diameter and grip codes.

Clause 4.4 introduces the first oversize “X” version, with separate data in Tables 7, 8 and 9. The oversize version has its own dimensions, grip range and mass values, and it is not available with the reduced diameter shifting anvil/drive washer. That means oversize must be selected deliberately, not assumed to be interchangeable with the standard part.

Material, finish, lubrication and marking

Clause 4.3 routes material, finish and lubrication to Tables 5 and 6. The tables distinguish the sleeve, serrated pin and locking collar materials, and they give sleeve finish codes. If lubrication is used, the document limits the choice to the listed lubricants. This matters because surface treatment and lubrication affect assembly behavior and corrosion performance.

Clause 6 specifies marking to EN 2424 style B on the fastener head. The marking needs the EN standard number, grip length code and manufacturer identification, while oversize bolts are marked with the letter “O”. That supports traceability during receiving inspection and in-service identification.

Clause 7 points to NASM8975 as the general technical specification, except for the strength, preload and spindle retention requirements defined here. In practice, the standard combines a general blind fastener specification with the specific performance values in Table 2.

What terms does FprEN 6127 define?

• Diameter code - the size code used throughout the tables to identify the bolt diameter and the related dimensions.
• Grip length code - the code that identifies the grip length range for the joint thickness.
• Grip range - the permitted joint thickness range for a given fastener size and grip length.
• First oversize “X” - the oversize version of the fastener, with its own designation, dimensions, grip range and mass.
• Material code - the designation element that identifies the material option used for the fastener parts.
• Finish code - the designation element that identifies the sleeve finish option.
• Spindle retention - the minimum retention performance stated in Table 2 after installation.

Who uses FprEN 6127?

FprEN 6127 is used by aerospace fastener manufacturers, aircraft and component assemblers, quality assurance staff, inspectors and procurement teams. Design engineers use it to choose the correct diameter, grip length, finish and oversize option. Buyers and suppliers use it to specify the exact part designation and check the required marking, materials and performance data. Test and inspection teams use it to verify dimensions, static strength, tensile preload and spindle retention.

What changed in FprEN 6127 from the previous edition?

FprEN 6127 will supersede ASD-STAN prEN 6127:2006. The foreword lists these technical changes:

• Figure 1 and Figure 2 were updated, with dimensions Q and X removed.
• Dimension Q was removed from Table 1.
• Table 1 and Table 3 were corrected for single values, and hole limits were removed.
• Tables 5 and 6 were updated to reflect the current normative references and preferred options.
• Oversize “X” was added to the document.

Which standards are used with FprEN 6127?

Clause 2 names the referenced documents that support marking, materials, coatings, lubricants and general fastener requirements:

• EN 2424 - marking of aerospace products.
• EN 4473 - aluminium pigmented coatings for fasteners.
• DOD-L-85645 - dry film lubricant.
• MIL-PRF-46010 - solid film lubricant, corrosion inhibiting.
• NASM8975 - general specification for blind fasteners.
• SAE AMS2700 - passivation of corrosion resistant steels.
• SAE AMS5687, SAE AMS5690 and SAE AMS5737 - material standards used for the listed alloy and steel options.
• SAE AS5272 and SAE AS87132 - lubricant specifications used when lubrication is applied.

What does the FprEN 6127 document contain?

The document contains the configuration figures, dimensional tables, grip range tables, mass tables, material and finish tables, and the first oversize “X” tables. It also contains the designation example, head marking rule and the technical specification reference. Figure 1 gives the part configuration, Figure 2 shows typical installation, and Tables 1 to 9 cover the standard and oversize variants. In practice, these tables are used for design definition, part selection, manufacturing control and inspection.

SLOVENSKI STANDARD
oSIST prEN 6127:2024
01-oktober-2024
Aeronavtika - Slepa kovica, 100° zmanjšana ugrezna glava, visoka trdnost
Aerospace series - Blind bolt, 100° reduced flush head, high strength
Luft- und Raumfahrt - Blindbolzen, 100° reduzierter Senkkopf, hochfest
Série aérospatiale - Boulon aveugle, tête fraisée réduite 100°, haute résistance
Ta slovenski standard je istoveten z: prEN 6127
ICS:
49.030.20 Sorniki, vijaki, stebelni vijaki Bolts, screws, studs
oSIST prEN 6127:2024 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

oSIST prEN 6127:2024
oSIST prEN 6127:2024
DRAFT
EUROPEAN STANDARD
prEN 6127
NORME EUROPÉENNE
EUROPÄISCHE NORM
July 2024
ICS 49.030.20
English Version
Aerospace series - Blind bolt, 100° reduced flush head,
high strength
Série aérospatiale - Boulon aveugle, tête fraisée réduite Luft- und Raumfahrt - Blindbolzen, 100° reduzierter
100°, haute résistance Senkkopf, 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 6127:2024 E
worldwide for CEN national Members.

oSIST prEN 6127:2024
prEN 6127:2024 (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 and tolerances . 5
4.2 Grip range and mass . 5
4.3 Material, finish and lubrication . 5
4.4 First oversize . 5
5 Designation . 17
6 Marking . 17
7 Technical specification . 17
oSIST prEN 6127:2024
prEN 6127:2024 (E)
European foreword
This document (prEN 6127:2024) 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 ASD-STAN prEN 6127:2006.
This document includes the following significant technical changes with respect to ASD-
STAN prEN 6127:2006:
a) Figure 1 and Figure 2 updated (dimensions Q and X removed);
b) dimension Q removed in Table 1 accordingly;
c) Table 1 and Table 3: Single values corrected and hole limits removed;
d) Table 5 and Table 6 updated according updated normative references and preferred options;
e) oversize “X” added in document.
oSIST prEN 6127:2024
prEN 6127:2024 (E)
1 Scope
This document specifies the configuration, dimensions, tolerances and mass of a stainless steel blind bolt
with 100° reduced 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 6127:2024
prEN 6127:2024 (E)
4 Requirements
4.1 Configuration, dimensions and tolerances
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 and lubrication
Material, finish and lubrication shall be according to Table 5 and Table 6.
4.4 First oversize
First oversize shall be according to Table 7, Table 8 and Table 9.

a) Bolt configuration
oSIST prEN 6127:2024
prEN 6127:2024 (E)
b) Serrated pin geometry
Key
1 marking see Clause 6 5 grip
2 serrated pin 6 sleeve
3 locking collar 7 shifting anvil
4 crown height (C) 8 drive washer
a
Diameter of pin head shall not exceed “⌀D” max.
b
Fasteners 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 and dimensions

Key
1 grip
a
Blind side head may be installed on 7° max. slope.
Figure 2 — Typical installation
oSIST prEN 6127:2024
prEN 6127:2024 (E)
Table 1 — Dimensions and tolerances
Dimensions in mm (inch)
Diameter code
05 06 08
Theor. 7,37 9,07 12,19
⌀A
(0,290) (0,357) (0,480)
Ref.
1,32 1,65 2,31
B Ref.
(0,052) (0,065) (0,091)
0,25 0,25 0,31
C max.
(0,010) (0,010) (0,012)
0,584 0,762 1,016
0,508 0,686 0,914
H Gage HT
(0,023 0) (0,030 0) (0,040 0)
(0,020 0) (0,027 0) (0,036 0)
5,946 7,216 9,792
5,941 7,211 9,787
⌀W Gage Dia.
(0,234 1) (0,284 1) (0,385 5)
(0,233 9) (0,283 9) (0,385 3)
±0,03 4,14 5,03 6,58
⌀D
(±0,001) (0,163) (0,198) (0,259)
±0,13 9,53 9,53 9,53
a
⌀J
(±0,005) (0,375) (0,375) (0,375)
±1,52 3,56 4,06 4,83
N
(±0,060) (0,140) (0,160) (0,190)
3,05 3,81 4,83
⌀D max.
(0,120) (0,150) (0,190)
2,16 2,79 3,66
⌀D max.
(0,085) (0,110) (0,144)
7,62 8,13 9,40
b
P max.
(0,300) (0,320) (0,370)
5,66 6,86 9,02
⌀P min.
(0,223) (0,270) (0,355)
0,25 0,38 0,51
R max.
(0,010) (0,015) (0,020)
5,89 7,42 9,17
S max.
(0,232) (0,292) (0,361)
±0,76 20,32 21,08 24,77
J
(±0,030) (0,800) (0,830) (0,975)
oSIST prEN 6127:2024
prEN 6127:2024 (E)
Diameter code
05 06 08
Number of
serrations
J 18 19 20
min.
±0,76 1,52 1,78 2,29
X
(±0,030) (0,060) (0,070) (0,090)
0,13 0,13 0,13
E min.
(0,005) (0,005) (0,005)
0,33 0,33 0,33
C Ref.
(0,013) (0,013) (0,013)
±0,05 0,81 0,81 0,81
C
(±0,002) (0,032) (0,032) (0,032)
F ±5° 45° 45° 45°
G ±5° 30° 30° 30°
a
Diameter code 05 is also available with reduced diameter shifting anvil/drive washer [7,93 mm ± 0,13 mm
(0,312 inch ± 0,005 inch)]. See part number examples.
b
In the length of P, ⌀D may be 0,05 mm (0,002 inch) undersize.
Table 2 — Static strength (installed), tensile preload, spindle retention
Dimensions in kN (lbf)
Diameter code Single shear Tensile Tensile preload Spindle retention
strength strength
min. min. min. min.
8,807 4,671 0,467 2,335
(1 980) (1 050) (105) (525)
13,011 6,672 0,667 3,336
(2 925) (1 500) (150) (750)
22,242 11,565 1,157 5,783
(5 000) (2 600) (260) (1 300)
oSIST prEN 6127:2024
prEN 6127:2024 (E)
Table 3 — Grip range
Dimensions in mm (inch)
Grip Under lap Grip range Over Diameter code
length lap
05 06 08
code
min. min. min. max. max. L K L K L K
only 06 dia.   05 dia. Ref. max. Ref. max. Ref. max.
05 dia. to 08 to 08
dia. dia.
a
2,39 3,99 4,39 8,53 12,09 9,02 13,23
02 — — — —
(0,094) (0,157) (0,173) (0,336) (0,476) (0,355) (0,521)
b
3,71 3,56 3,96 5,59 5,99 10,11 13,69 10,59 14,83 12,17 16,38
(0,146) (0,140) (0,156) (0,220) (0,236) (0,398) (0,539) (0,417) (0,584) (0,479) (0,645)
5,31 5,16 5,56 7,16 7,57 11,68 15,29 12,19 16,43 13,74 17,98
(0,209) (0,203) (0,219) (0,282
...