SIST EN 4836:2018

Aerospace series - Adaptor, Pipe coupling 24° Cone up to 35 000 kPa (5 080 psi) Ring-locked fitting - Reducer - Flareless End - Inch Series - Extra Fine Thread Pitch

This European Standard specifies the dimensions, tolerances, required characteristics and the mass of a reducer, flareless tube end EN 6123, ring locked type, for use in 35 000 kPa (5 080 psi) working pressure systems.

Luft- und Raumfahrt - Adapter, Rohrverschraubung 24° Konus bis 35 000 kPa (5 080 psi) gerade Anschlussverschraubung, reduziertes Rohrende mit Sicherungsring - Inch Reihe - extra feine Gewindesteigung

Série aérospatiale - Adapteur, Système de raccordement interface conique 24° jusqu'á 35 000 kPa (5 080 psi) Implantation pour raccord avec bague de sécurité - Séries inch - Filetage à pas extra-fin

Aeronavtika - Adapter, Cevni priključek 24° Konica do 35 000 kPa (5080 psi) Navojni priključek z zapornim obročem in njegovim reduktorjem - Brez razširjenega končnika - Palčne mere - Ekstra fin navojni korak

Ta evropski standard določa dimenzije, odstopanja, zahtevane lastnosti in maso reduktorja, brez razširjenega končnika (EN 6123), z navojnim priključkom z zapornim obročem, za uporabo v tlačnih sistemih do 35 000 kPa (5080 psi).

General Information

• Status: Published
• Publication Date: 12-Sep-2018
• ICS: 49.080 - Aerospace fluid systems and components
• Technical Committee: I13 - Imaginarni 13
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 10-Aug-2018
• Due Date: 15-Oct-2018
• Completion Date: 13-Sep-2018
• Ref Project: EN 4836:2018 - Aerospace series - Adaptor, Pipe coupling 24° Cone up to 35 000 kPa (5 080 psi) Ring-locked fitting - Reducer - Flareless End - Inch Series - Extra Fine Thread Pitch

Relations

• Refers: SIST EN 4832:2018 - Aerospace series - Adaptor, Pipe coupling 24° Cone up to 35 000 kPa (5 080 psi) Ring-locked fitting and Ring-locked fitting-reducer - Inch Series - Technical specification
• Effective Date: 28-Jan-2026
• Refers: SIST EN 4835:2018 - Aerospace series - Installation and removal requirements for Ring locked fitting and reducer, 24° Cone up to 35 000 kPa (5 080 psi) - Inch Series
• Effective Date: 28-Jan-2026
• Refers: SIST EN 10244-1:2009 - Steel wire and wire products - Non-ferrous metallic coatings on steel wire - Part 1: General principles
• Effective Date: 28-Jan-2026
• Refers: SIST EN 4315:2026 - Aerospace series - Heat-resisting alloy X4NiCrTiMoV26-15 (1.4980) - Solution treated and precipitation treated - Bars and sections - a or D ≤ 100 mm - Rm ≥ 900 MPa
• Effective Date: 28-Jan-2026
• Refers: SIST EN 4317:2026 - Aerospace series - Heat-resisting alloy X4NiCrTiMoV26-15 (1.4980) - Non heat treated - Forging stock - a or D ≤ 200 mm
• Effective Date: 28-Jan-2026
• Refers: SIST EN 3311:2024 - Aerospace series - Titanium alloy TI-P64001 (Ti-6Al-4V) - Annealed - Bars for machining - D ≤ 300 mm - 900 MPa ≤ Rm ≤ 1 160 MPa
• Effective Date: 28-Jan-2026
• Refers: SIST EN 6123:2016 - Aerospace series - Fitting end, 24° internal cone, external thread, flareless type - Inch series - Design standard
• Effective Date: 28-Jan-2026
• Refers: SIST EN 2424:2008 - Aerospace series - Marking of aerospace products
• Effective Date: 28-Jan-2026
• Referred By: SIST EN 4834:2018 - Aerospace series - Adaptor, Pipe coupling 24° Cone up to 35 000 kPa (5 080 psi) Port for Ring locked fitting - Inch Series - Geometric configuration
• Effective Date: 28-Jan-2026

Overview

SIST EN 4836:2018, titled "Aerospace series - Adaptor, Pipe coupling 24° Cone up to 35 000 kPa (5 080 psi) Ring-locked fitting - Reducer - Flareless End - Inch Series - Extra Fine Thread Pitch," is a European standard developed by the Slovenian Institute for Standardization (SIST). This standard defines the dimensions, tolerances, essential characteristics, and mass for a flareless tube end reducer (EN 6123, ring-locked type) designed for use in high-pressure aerospace fluid systems operating up to 35 000 kPa (5 080 psi). The document supports interoperability and high performance in critical aerospace environments by ensuring reliable and standardized connections in pressurized hydraulic and fluid lines.

Key Topics

• Scope and Purpose: Specifies reducer fittings with extra fine thread pitch for aerospace applications, guaranteeing compatibility up to 35 000 kPa (5 080 psi).
• Design Specifications: Covers the configuration, dimensions, tolerances (linear, angular), surface finishes, and required markings for these fittings.
• Material and Treatment Requirements: References relevant material standards and surface treatments, including titanium and corrosion-resistant alloys, and applicable finishing and coating procedures.
• Marking and Packaging: Outlines durability and traceability requirements for manufacturer markings as per EN 2424, and suitable packaging for damage prevention.
• Quality Assurance: Requires manufacturers to have quality management systems in accordance with EN 9100 and provides for inspections and qualification testing.
• International Compatibility: Establishes equivalence with AS5865 and references cross-compatible standards, facilitating global procurement and application.

Applications

SIST EN 4836:2018 is widely utilized in aerospace and defense industries where high-pressure fluid systems demand secure, leak-proof, and standardized connections. Its practical value extends to:

• Aircraft Hydraulic Systems: Ensures reliable performance in landing gear, flight control, and brake systems where hydraulic lines operate under extreme pressures.
• Aerospace Fluid Handling: Suitable for fuel, coolant, and lubrication piping, ensuring consistent system integrity throughout the lifespan of the aircraft.
• Maintenance and Repair: Offers clear interchangeability with equivalent parts (e.g., AS5865) for efficient replacement and compatibility, reducing downtime and facilitating maintenance operations.
• Global Supply Chain Integration: Adherence to both European (EN) and international (AS/SAE) norms simplifies sourcing and promotes widespread industry acceptance.

Related Standards

SIST EN 4836:2018 is supported and complemented by several recognized aerospace and fluid system standards, including:

• EN 6123: Fitting end, 24° internal cone, external thread, flareless type - provides design standards for compatible tube ends.
• EN 4832: Technical specification for ring-locked fittings for 24° cone applications.
• EN 4835: Installation and removal procedures for ring-locked fittings in aerospace systems.
• EN 9100: Quality Management Systems for Aviation, Space, and Defence Organizations.
• AS5865: Functional equivalent standard for parts defined in EN 4836, ensuring interchangeability.
• AMS and ISO Standards: References to material, heat treatment, and surface finish procedures (e.g., AMS 2486, ISO 3161 for UNJ threads).

These related standards facilitate safe, standardized, and efficient practices across the aerospace sector, making SIST EN 4836:2018 a key reference for engineers, manufacturers, and maintenance teams working with high-pressure aerospace fluid systems.

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Keywords: SIST EN 4836:2018, aerospace pipe coupling, 24° cone, high-pressure reducer fitting, ring-locked fitting, flareless tube end, extra fine thread, fluid system standard, inch series, aerospace hydraulic connections, standardization.

Standards Content (Sample)

SLOVENSKI STANDARD
01-oktober-2018
$HURQDYWLND$GDSWHU&HYQLSULNOMXþHNƒ.RQLFDGRN3DSVL
1DYRMQLSULNOMXþHN]]DSRUQLPREURþHPLQQMHJRYLPUHGXNWRUMHP%UH]
UD]ãLUMHQHJDNRQþQLND3DOþQHPHUH(NVWUDILQQDYRMQLNRUDN
Aerospace series - Adaptor, Pipe coupling 24° Cone up to 35 000 kPa (5 080 psi) Ring-
locked fitting - Reducer - Flareless End - Inch Series - Extra Fine Thread Pitch
Luft- und Raumfahrt - Adapter, Rohrverschraubung 24° Konus bis 35 000 kPa (5 080
psi) gerade Anschlussverschraubung, reduziertes Rohrende mit Sicherungsring - Inch
Reihe - extra feine Gewindesteigung
Série aérospatiale - Adapteur, Système de raccordement interface conique 24° jusqu'á
35 000 kPa (5 080 psi) Implantation pour raccord avec bague de sécurité - Séries inch -
Filetage à pas extra-fin
Ta slovenski standard je istoveten z: EN 4836:2018
ICS:
49.080 /HWDOVNLLQYHVROMVNL Aerospace fluid systems and
KLGUDYOLþQLVLVWHPLLQGHOL components
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN 4836
EUROPEAN STANDARD
NORME EUROPÉENNE
August 2018
EUROPÄISCHE NORM
ICS 49.080
English Version
Aerospace series - Adaptor, Pipe coupling 24° Cone up to
35 000 kPa (5 080 psi) Ring-locked fitting - Reducer -
Flareless End - Inch Series - Extra Fine Thread Pitch
Série aérospatiale - Adapteur, Système de Luft- und Raumfahrt - Adapter, Rohrverschraubung
raccordement interface conique 24° jusqu'á 35 000 kPa 24° Konus bis 35 000 kPa (5 080 psi) gerade
(5 080 psi) Implantation pour raccord avec bague de Anschlussverschraubung, reduziertes Rohrende mit
sécurité - Séries inch - Filetage à pas extra-fin Sicherungsring - Inch-Reihe - extra feine
Gewindesteigung
This European Standard was approved by CEN on 6 December 2017.

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. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This European Standard exists 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, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2018 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 4836:2018 E
worldwide for CEN national Members.

Contents Page
European foreword . 3
Introduction . 4
1 Scope . 5
2 Normative references . 5
3 Requirements . 6
4 Quality assurance . 10
5 Designation . 10
6 Marking . 11
7 Packaging . 11
8 Technical Specification . 11
9 REACH . 11
Bibliography . 12

European foreword
This document (EN 4836:2018) 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 Standard has
received the approval of the National Associations and the Official Services of the member countries of
ASD, prior to its presentation to CEN.
This European Standard shall be given the status of a national standard, either by publication of an
identical text or by endorsement, at the latest by February 2019, and conflicting national standards
shall be withdrawn at the latest by February 2019.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta,
Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden,
Switzerland, Turkey and the United Kingdom.
Introduction
This European Standard is co-owned standard and a functional equivalent of AS5865. There should be
no technical objection to use AS5865 as replacement of EN 4836 parts. Table 3 shows the equivalent
cross reference of EN 4836 part numbers to AS5865 part numbers. Further revisions to this standard
shall be coordinated with the SAE committee.
European standards use the International System of units (SI); however, large segments of the
aerospace industry make use of other measurement systems as a matter of common working practice.
All dimensions and units used in this standard are given in SI units, with other units also indicated for
the convenience of the user.
The decimal sign used in European standards is the comma (“,”); however, the comma is not used in
common working practice with non-SI dimensions. Therefore, in common with many other aerospace
standards, the decimal point (“.”) is used in this standard when providing dimensions in inch-pound
units.
NOTE The use of non-SI units and the decimal point in this standard does not constitute general acceptance
of measurement systems other than SI within European standards.
1 Scope
This European Standard specifies the dimensions, tolerances, required characteristics and the mass of
a reducer, flareless tube end EN 6123, ring locked type, for use in 35 000 kPa (5 080 psi) working
pressure systems.
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 3311, Aerospace series — Titanium alloy TI-P64001 (Ti-6Al-4V) — Annealed — Bar for machining
D < 110 mm
EN 3314, Aerospace series — Titanium alloy TI-P64001, solution treated and aged; bar for machining
D ≤ 75 mm
EN 4315, Aerospace series — Heat resisting alloy FE-PA2601 (X6NiCrTiMoV26-15) — Solution treated
and precipitation treated, bar and section a or D ≤ 100 mm, R ≥ 900 MPa
m
EN 4317, Aerospace series — Heat resisting alloy FE-PA2601 (X6NiCrTiMoV26-15) — Non heat treated,
forging stock a or D ≤ 200 mm
EN 4832, Aerospace series — Pipe coupling 24°Cone up to 35 000 kPa (5 080 psi) Ring-locked fitting and
1)
Ring-locked fitting-reducer — Inch Series — Technical specification
EN 4835, Aerospace series — Installation and removal requirements for Ring locked fitting and reducer,
1)
24° Cone up to 35 000 kPa (5 080 psi) — Inch Series
EN 6123, Aerospace series — Fitting end, 24° internal cone, external thread, flareless type — Extra fine
thread pitch — Inch series — Design standard
ISO 1302, Geometrical Product Specifications (GPS) — Indication of surface texture in technical product
documentation
ISO 3161, Aerospace — UNJ threads — General requirements and limit dimensions
ISO 4287, Geometrical Product Sp
...