oSIST prEN 3196:2026

• Abstract:

  This document specifies the characteristics of self-locking hexagonal nuts in FE-PA92HT, silver plated, for aerospace applications.; Classification: 1 100 MPa1/425 °C2.

• Status: Not Published
• Public Enquiry End Date: 09-Jul-2026
• ICS: 49.025.10 - Steels
• ICS: 49.030.30 - Nuts
• Technical Committee: I13 - Imaginarni 13
• Current Stage: 4020 - Public enquire (PE) (Adopted Project)
• Start Date: 21-May-2026
• Due Date: 08-Oct-2026
• Completion Date: 10-Jul-2026
• Ref Project: prEN 3196 - Aerospace series — Nuts, hexagonal, self-locking, in heat resisting steel FE-PA92HT (A286), silver plated - Classification : 1 100 MPa (at ambient temperature) / 425 °C

• Revises: SIST EN 3196:2001 - Aerospace series - Nuts, hexagonal, self-locking, in heat resisting steel FE-PA92HT (A286), silver plated - Classification: 1 100 MPa (at ambient temperature) / 425 °C
• Effective Date: 20-Jan-2026

oSIST prEN 3196:2026 is a CEN draft European Standard for aerospace series self-locking hexagonal nuts made from heat resisting steel FE-PA92HT (A286) and silver plated. It specifies the characteristics of these nuts for aerospace applications at classification 1 100 MPa (at ambient temperature) / 425 °C, so it is aimed at designers, manufacturers, quality staff, and buyers who need the exact product definition.

What does oSIST prEN 3196:2026 specify?

oSIST prEN 3196:2026 specifies the product characteristics, identification, marking, and technical specification for self-locking hexagonal nuts in FE-PA92HT (A286), silver plated, for aerospace use. The document is organized into scope, normative references, terms and definitions, required characteristics, designation, marking, and technical specification.

The key technical content sits in Clause 4, which ties the nut geometry, materials, and surface treatment to figures, tables, and referenced standards. Clauses 5 to 7 then show how to name the nut, how to mark it, and what production approval and qualification approach applies.

What are the key requirements of oSIST prEN 3196:2026?

oSIST prEN 3196:2026 focuses on a few practical points that control interchangeability, surface condition, and product acceptance.

• Classification - The nuts are classified for 1 100 MPa at ambient temperature and 425 °C maximum test temperature. In practice, this tells the user the load and temperature class the nut is intended to match.
• Configuration, dimensions, tolerances, and mass - Clause 4.1 requires conformance to Figure 1 and Table 1, with dimensions in millimetres and applied after silver plating. In practice, the finished nut must match the stated envelope, and inspection is based on the plated part.
• Thread and fit - The dimensions are stated as MJ threads, with the thread-related limits tied to ISO 5855-2 and ISO 7995. In practice, the nut has to work with the aerospace MJ thread system and remain compatible with the intended wrench engagement.
• Materials - Clause 4.2 allows materials from EN 2399, EN 3638, EN 3639, TR 3791, or, for MJ3 and MJ4, SAE AMS5525 at the manufacturer’s discretion. In practice, the supplier has some material-route choice, but only within the listed aerospace material standards.
• Surface treatment - Clause 4.3 requires electrolytic silver plating in accordance with EN 2786, with specific coverage expectations for external surfaces and thread flanks. In practice, plating quality matters for corrosion performance, electrical behavior, and fit after coating.
• Designation and marking - Clause 5 defines how the nut is designated, and Clause 6 ties marking to EN 2424 and to the diameter code family. In practice, the designation and marking let users identify the correct nut type on drawings, stock, and received parts.
• Technical specification - Clause 7 links the product to EN 3152 and adds approval and qualification expectations. In practice, manufacturers need an aerospace quality system and a documented qualification procedure before supplying the parts.
• Manufacturing condition - The configuration notes that sharp edges are to be removed and that the finished nut must fit a standard socket wrench. In practice, this controls usability during assembly and reduces damage risk.

Who uses oSIST prEN 3196:2026?

oSIST prEN 3196:2026 is used by aerospace fastener manufacturers, procurement teams, quality managers, and design engineers who specify or verify self-locking nuts. It is also relevant to qualification laboratories and approved production organizations that need to confirm material selection, plating, marking, and product conformity for aerospace hardware.

What changed in oSIST prEN 3196:2026 from the previous edition?

oSIST prEN 3196:2026 supersedes EN 3196:1994. The draft states these significant changes:

• Clause 3, Terms and definitions, was added.
• Clause 4.2 adds TR 3791 and SAE AMS5525 among the material references.
• Clause 7, Technical specification, was editorially revised.

Which standards are used with oSIST prEN 3196:2026?

Standard	What it contributes
EN 2399	One of the listed material standards for the nut material.
EN 2424	Aerospace product marking.
EN 2786	Electrolytic silver plating of fasteners.
EN 3152	Base technical specification for self-locking nuts, with modifications here.
EN 3638	Listed heat-resisting alloy sheet, strip, and plate material reference.
EN 3639	Listed wire material reference for forged fasteners.
ISO 5855-2	Limit dimensions for MJ bolts and nuts.
ISO 7995	Dimensions for self-locking hexagonal nuts with MJ threads.
TR 3791	Materials for self-locking nuts and threaded inserts up to 425 °C.
SAE AMS5525	Alternative material standard for MJ3 and MJ4 at manufacturer discretion.
EN 9100	Example quality management system for manufacturer approval.
EN 9133	Example qualification procedure for aerospace standard products.

What does the oSIST prEN 3196:2026 document contain?

oSIST prEN 3196:2026 contains Figure 1 and Table 1 for the nut configuration, dimensions, tolerances, and mass. It also includes the surface treatment requirements, a designation clause, and a marking clause that links the product to EN 2424. Clause 7 sets the technical specification framework for manufacturer approval and product qualification, which is what suppliers and auditors use to control production readiness and acceptance.

SLOVENSKI STANDARD
01-julij-2026
Aeronavtika - Matice, šestrobe, samozapiralne, iz toplotnoodpornega jekla FE-
PA92HT (A286), posrebrene - Klasifikacija: 1100 MPa (pri temperaturi okolice)/425
°C
Aerospace series - Nuts, hexagonal, self-locking, in heat resisting steel FE-PA92HT
(A286), silver plated - Classification : 1 100 MPa (at ambient temperature) / 425 °C
Luft‑ und Raumfahrt - Sechskantmutter, selbstsichernd, aus hochwarmfesten Stahl
FE‑PA92HT (A286), versilbert - Klasse: 1 100 MPa (bei Raumtemperatur)/425 °C
Ta slovenski standard je istoveten z: prEN 3196
ICS:
49.025.10 Jekla Steels
49.030.30 Matice Nuts
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

DRAFT
EUROPEAN STANDARD
NORME EUROPÉENNE
EUROPÄISCHE NORM
April 2026
ICS 49.030.30 Will supersede EN 3196:1994
English Version
Aerospace series - Nuts, hexagonal, self-locking, in heat
resisting steel FE-PA92HT (A286), silver plated -
Classification : 1 100 MPa (at ambient temperature) / 425
°C
Luft- und Raumfahrt ¿ Sechskantmutter,
selbstsichernd, aus hochwarmfesten Stahl FE-PA92HT
(A286), versilbert ¿ Klasse: 1 100 MPa (bei
Raumtemperatur)/425 °C
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
© 2026 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 3196:2026 E
worldwide for CEN national Members.

Contents Page
European foreword . 3
1 Scope . 4-s
2 Normative references . 4
3 Terms and definitions . 5
4 Required characteristics . 5
4.1 Configuration – Dimensions – Tolerances – Mass . 5
4.2 Materials . 5
4.3 Surface treatment . 5
5 Designation . 8
6 Marking . 8
7 Technical specification . 8
7.1 General. 8
7.2 Approval of manufacturers . 8
7.3 Qualification of products . 8
Bibliography . 9

European foreword
This document (prEN 3196:2026) 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 3196:1994.
EN 3196:1994:
— Clause 3, “Terms and definitions”, added;
— 4.2, “Materials”, standards TR 3791 and SAE AMS5525 added;
— Clause 7, “Technical specification”, editorially revised.
1 Scope
This document specifies the characteristics of self-locking hexag
...