kSIST FprEN 4265:2026

Aerospace series - Bearing spherical plain, metal to metal in corrosion resisting steel - Wide series - Dimensions and loads - Inch series

This document specifies the characteristics of spherical plain bearings, metal to metal, in corrosion resisting steel, passivated, wide series, inch series for aerospace applications.
Spherical plain bearings, metal to metal, in corrosion resisting steel, passivated, wide series, are intended for use in fixed or moving parts of the aircraft structure and their control mechanisms.
Spherical plain bearings, metal to metal, in corrosion resisting steel, passivated, wide series, are intended for use in the following temperature range, −54 °C to 150 °C, and intended to be lubricated by means of the following greases:
- Code A: grease conforming to MIL-PRF-23827, operating temperature range −73 °C to 121 °C;
- Code B: grease conforming to MIL-PRF-81322, operating temperature range −54 °C to 177 °C.
For the purposes of this document, the range of application for bearings lubricated with grease conforming to code A is limited to 121 °C.
For the purposes of this document, the range of applications for bearings lubricated with grease conforming to code B is limited to 177 °C.
NOTE In both cases it is important to provide the spherical surface of the outer or inner ring with a dry-film lubricant conforming to MIL-PRF-46010 or equivalent (anti-seizing protection).

Luft- und Raumfahrt - Gelenklager, Metall auf Metall aus korrosionsbeständigem Stahl - Breite Reihe - Maße und Belastungen - Inch-Reihe

No Scope available

Série aérospatiale - Rotule lisse, métal à métal en acier résistant à la corrosion - Série large - Dimensions et charges - Série en inches

Le présent document spécifie les caractéristiques des rotules lisses, métal à métal, en acier résistant à la corrosion, passivées, série large, série en inches, pour les applications aérospatiales.
Les rotules lisses, métal à métal, en acier résistant à la corrosion, passivées, série large, sont destinées à être utilisées pour les parties fixes ou mobiles de la structure de l’aéronef et leurs mécanismes de commande.
Les rotules lisses, métal à métal, en acier résistant à la corrosion, passivées, série large, sont destinées à être utilisées dans une plage de températures de −54 °C à 150 °C, et à être lubrifiées à l’aide des graisses suivantes :
—   code A : graisse conforme à la MIL-PRF-23827, plage de températures de fonctionnement de −73 °C à 121 °C ;
—   code B : graisse conforme à la MIL-PRF-81322, plage de températures de fonctionnement de −54 °C à 177 °C.
Pour les besoins du présent document, la plage d’application des rotules lubrifiées à l’aide de graisse conforme au code A est limitée à 121 °C.
Pour les besoins du présent document, la plage d’application des rotules lubrifiées à l’aide de graisse conforme au code B est limitée à 177 °C.
NOTE   Dans les deux cas, il est important d'appliquer sur la surface sphérique de la bague extérieure ou intérieure un lubrifiant à film sec conforme à la MIL-PRF-46010 ou équivalente (protection anti-grippage).

Aeronavtika - Ležaj, krogelni, drsni, kovina na kovino, iz korozijsko odpornega jekla - Široki tip - Mere in obremenitve - Colske serije

General Information

• Status: Not Published
• Public Enquiry End Date: 19-Nov-2024
• ICS: 21.100.01 - Bearings in general
• ICS: 49.035 - Components for aerospace construction
• Technical Committee: I13 - Imaginarni 13
• Current Stage: 5020 - Formal vote (FV) (Adopted Project)
• Start Date: 07-May-2026
• Due Date: 25-Jun-2026
• Completion Date: 08-May-2026
• Ref Project: FprEN 4265 - Aerospace series - Bearing spherical plain, metal to metal in corrosion resisting steel - Wide series - Dimensions and loads - Inch series

Relations

• Revises: SIST EN 4265:2014 - Aerospace series - Bearing spherical plain, metal to metal in corrosion resisting steel - Wide series - Dimensions and loads - Inch series
• Effective Date: 03-May-2023

Overview

kSIST FprEN 4265:2026 is a forthcoming European standard developed by SIST that specifies the characteristics of spherical plain bearings, metal to metal, in corrosion resisting steel, passivated, wide series, inch series, intended for aerospace applications. These bearings are engineered for high-performance environments, supporting both fixed and moving parts within aircraft structures and control systems. The standard details dimensional requirements, permissible loads, material specifications, and relevant lubrication guidelines to ensure safety and reliability in critical aerospace sectors.

Key Topics

• Product Scope: Covers spherical plain bearings, wide series, composed of metal to metal contact surfaces, constructed from corrosion resistant steel, and passivated for enhanced durability.
• Applications: Intended for fixed or moving components of aircraft structures and their control mechanisms.
• Dimensional Requirements: Specifies inch-based series dimensions, tolerances, and mass.
• Materials & Surface Protection:
  • Inner rings: Hardened steel according to EN 2030.
  • Outer rings: Steel as per EN 3161 or alternatives per TR 4661.
  • Passivation and surface treatments conforming to ISO 8075.
• Temperature Range: Operational from −54 °C to 150 °C, dependent on lubrication type.
• Lubrication:
  • Code A: MIL-PRF-23827 grease for operation up to 121 °C.
  • Code B: MIL-PRF-81322 grease for operation up to 177 °C.
  • Application of dry-film lubricants as per MIL-PRF-46010 for anti-seizing protection strongly recommended.
• Load Ratings & Clearances: Details permissible static and ultimate load values, with associated clearances as specified in referenced tables.
• Marking and Designations: Bearings are to be marked according to EN 2424 and the manufacturer's requirements.

Applications

Spherical plain bearings compliant with kSIST FprEN 4265:2026 provide critical functionality in aerospace engineering by enabling pivoting, oscillation, or rotational motion between coupled parts under varying loads and conditions. Key applications include:

• Aircraft Structure and Controls: Used at hinge points, actuators, and mechanical linkages to accommodate misalignment and movement.
• Landing Gear Assemblies: Ensures reliable operation under dynamic and extreme environmental conditions.
• Flight Control Systems: Facilitates smooth articulation and reliable mechanical response.
• Aerospace Mechanisms Exposed to Corrosive Environments: Corrosion resisting steel and passivation provide longevity in harsh aerospace settings.

These bearings are selected for their strength, resistance to corrosion, and capacity to operate effectively over a wide temperature range, ensuring safety and performance in mission-critical aerospace hardware.

Related Standards

To achieve full compliance and optimal integration, this standard references several key documents:

• EN 2030: Aerospace series - Hardened and tempered steel for inner ring manufacture.
• EN 3161: Aerospace series - Steel for outer ring construction.
• EN 2337: Spherical plain bearings - Technical specification and clearances.
• EN 2424: Marking of aerospace products.
• ISO 8075: Surface treatment of hardenable stainless steel parts.
• TR 4475 and TR 4661: Vocabulary, material selection, and surface treatments for aerospace bearings.
• MIL-PRF-23827 & MIL-PRF-81322: Aerospace greases, specifying lubricants for wide and limited temperature applications.
• MIL-PRF-46010: Solid film lubricant for anti-seizing and corrosion-inhibition.

Practical Value

Implementing kSIST FprEN 4265:2026 ensures standardized performance, material quality, and safety for aerospace spherical plain bearings. Manufacturers and aerospace engineers benefit from reliable design guidelines, compatibility with international product lines, and enhanced product lifecycle through rigorous corrosion resistance and precise lubrication requirements. Adoption of this standard is essential for meeting European and international regulatory requirements in aerospace manufacturing and maintenance.

Standards Content (Sample)

SLOVENSKI STANDARD
oSIST prEN 4265:2024
01-november-2024
Aeronavtika - Ležaj, krogelni, drsni, kovina na kovino, iz korozijsko odpornega
jekla - Široki tip - Mere in obremenitve - Colske serije
Aerospace series - Bearing spherical plain, metal to metal in corrosion resisting steel -
Wide series - Dimensions and loads - Inch series
Luft- und Raumfahrt - Gelenklager, Metall auf Metall aus korrosionsbeständigem Stahl -
Breite Reihe - Maße und Belastungen - Inch-Reihe
Série aérospatiale - Rotule lisse, métal à métal en acier résistant à la corrosion - Série
large - Dimensions et charges - Série en inches
Ta slovenski standard je istoveten z: prEN 4265
ICS:
21.100.01 Ležaji na splošno Bearings in general
49.035 Sestavni deli za letalsko in Components for aerospace
vesoljsko gradnjo construction
oSIST prEN 4265:2024 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

oSIST prEN 4265:2024
oSIST prEN 4265:2024
DRAFT
EUROPEAN STANDARD
prEN 4265
NORME EUROPÉENNE
EUROPÄISCHE NORM
August 2024
ICS 49.035 Will supersede EN 4265:2013
English Version
Aerospace series - Bearing spherical plain, metal to metal
in corrosion resisting steel - Wide series - Dimensions and
loads - Inch series
Série aérospatiale - Rotules lisses, métal à métal en Luft- und Raumfahrt - Gelenklager, Metall auf Metall
acier résistant à la corrosion - Série large - Dimensions aus korrosionsbeständigem Stahl - Breite Reihe - Maße
et charges - Séries en inches und Belastungen - Inch-Reihe
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 4265:2024 E
worldwide for CEN national Members.

oSIST prEN 4265:2024
prEN 4265:2024 (E)
Contents Page
European foreword . 3
1 Scope . 4
2 Normative references . 4
3 Terms and definitions . 4
4 Symbols and abbreviations . 5
5 Requirements . 5
5.1 Configuration, dimensions, tolerances and mass. 5
5.2 Surface roughness . 5
5.3 Material . 5
5.4 Surface treatment . 5
5.5 Loads and clearances . 5
6 Designation . 14
7 Marking . 14
8 Technical specification . 14
Bibliography . 15
oSIST prEN 4265:2024
prEN 4265:2024 (E)
European foreword
This document (prEN 4265:2024) has been prepared by the Aerospace and Defence Industries
Association of Europe — Standardization (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 4265:2013.
This document includes the following significant technical changes with respect to EN 4265:2013:
— Value for the outer diameter for diameter code 05 in Table 1 corrected;
— Reference on TR 4661 for alternative materials added.
oSIST prEN 4265:2024
prEN 4265:2024 (E)
1 Scope
This document specifies the characteristics of spherical plain bearings, metal to metal, in corrosion
resisting steel, passivated, wide series, inch series for aerospace applications.
They are intended for use in fixed or moving parts of the aircraft structure and their control
mechanisms.
They are used in the temperature range −54 °C to 150 °C. As they are lubricated by means of the
following greases:
Code A: Grease as per MIL-PRF-23827C, operating temperature range −73 °C to 121 °C.
Code B: Grease as per MIL-PRF-81322G, operating temperature range −54 °C to 177 °C.
The range of application for bearings lubricated with grease per code A is limited to 121 °C.
In both cases it is important to provide the spherical surface of the outer or inner ring with a dry-film
lubricant as per MIL-PRF-46010G or equivalent (anti-seizing protection).
The slide hole treatment either at the outer ring or inner ring.
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 2030, Aerospace series — Steel X105CrMo17 (1.3544) — Hardened and tempered — Bars — De ≤ 150
mm
EN 2337, Aerospace series — Spherical plain bearings — Technical specification
EN 2424, Aerospace series — Marking of aerospace products
EN 3161, Aerospace series — Steel FE-PM3801 (X5CrNiCu17-4) — Air melted, solution treated and
precipitation treated, bar a or D ≤ 200 mm, Rm ≥ 930 MPa
ISO 1132-1, Rolling bearings — Tolerances — Part 1: Terms and definitions
ISO 8075, Aerospace — Surface treatment of hardenable stainless steel parts
TR 4475, Aerospace series — Bearings and mechanical transmissions for airframe applications —
Vocabulary
TR 4661, Aerospace series — Bearings, flight controls — Materials and surface treatments
3 Terms and definitions
For the purposes of this document, the terms and definitions given in TR 4475 apply.
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 as ASD-STAN Technical Report at the date of publication of this document, (www.asd-stan.org).
oSIST prEN 4265:2024
prEN 4265:2024 (E)
4 Symbols and abbreviations
Symbols of limit deviations are in accordance with definitions of ISO 1132-1.
α is the maximum angle of tilt of the outer ring with respect to the inner ring, with the
sp
...