SIST EN 4184:2004

• Abstract:

  This standard specifies the characteristics of elbows 45°, welded ends, for pipe couplings 8°30', in titanium alloy, for; aerospace applications.; Nominal pressure: up to 28 000 kPa; Temperature range: 55 C to 135 C

• Status: Published
• Publication Date: 30-Apr-2004
• ICS: 49.080 - Aerospace fluid systems and components
• Technical Committee: I08 - Imaginarni 08
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 01-May-2004
• Due Date: 01-May-2004
• Completion Date: 01-May-2004
• Ref Project: EN 4184:2001 - Aerospace series - Pipe coupling 8°30' in titanium alloy - Elbows 45° double, welded ends

• Refers: SIST EN 2656:2002 - Aerospace series - Pipe coupling - Coupling end, welded - Geometric configuration
• 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 3312:2012 - Aerospace series - Titanium alloy Ti-6Al-4V - Annealed - Forgings De ≤ 150 mm
• Effective Date: 28-Jan-2026
• Refers: SIST EN 2424:2008 - Aerospace series - Marking of aerospace products
• Effective Date: 28-Jan-2026
• Refers: SIST EN 3275:2019 - Aerospace series - Pipe coupling 8°30' up to 28 000 kPa Dynamic beam seal - Metric series - Technical specification
• Effective Date: 28-Jan-2026

SIST EN 4184:2004 is the Slovenian standard published by SIST and identical to EN 4184:2001. It specifies 45° double elbows with welded ends for 8°30' pipe couplings in titanium alloy for aerospace applications. In practice, it gives designers, manufacturers and buyers the component geometry, material options, marking and linked technical specification they need to specify and accept the part.

What does SIST EN 4184:2004 specify?

SIST EN 4184:2004 specifies the characteristics of elbows 45°, welded ends, for pipe couplings 8°30', in titanium alloy, for aerospace applications. It is organized in six clauses, with Figure 1 and Table 1 providing the part geometry, size coding, dimensions and mass.

The standard sets the intended pressure and temperature envelope in the scope: nominal pressure up to 28 000 kPa and a temperature range of 55 °C to 135 °C. That matters because the part is not a general-purpose elbow - it is defined for a specific aerospace coupling family and operating range.

The main content is structured as:

• Clause 1 - Scope
• Clause 2 - Normative references
• Clause 3 - Required characteristics
• Clause 4 - Designation
• Clause 5 - Marking
• Clause 6 - Technical specification

What are the key requirements of SIST EN 4184:2004?

SIST EN 4184:2004 defines the part by its configuration, material, finish and marking, and it ties several choices to other aerospace standards. The most important point for users is that the geometry and acceptance rules are not all fixed in this document - some are controlled through referenced standards.

Configuration, dimensions and mass

Clause 3.1 states that the configuration, dimensions and mass follow Figure 1 and Table 1. Dimensions not specified in the standard are left to the manufacturer, but only if the qualification and acceptance requirements of EN 3275, type II, are met.

In practice, this means the drawing and part number must match the coded sizes in the table, while any non-specified dimension still has to pass the linked qualification and acceptance route.

Surface roughness

Clause 3.2 sets the surface roughness according to Figure 1, unless the design documentation says otherwise. This gives the surface finish a controlled status rather than leaving it informal.

For a manufacturer, that means finish control belongs in the drawing package and inspection plan. For a buyer, it means the surface condition is part of the defined product, not an afterthought.

Materials

Clause 3.3 points to titanium alloy material requirements in EN 3311 or EN 3314, and EN 3312 or EN 3315. These references cover the specified titanium alloy forms and heat-treatment conditions used for the part.

In practice, procurement and quality teams need to verify that the supplied stock or forging route matches one of the listed material standards, because material condition is part of the defined product.

Designation

Clause 4 gives the designation system and includes a note that, if needed, code I9005 is placed between the description block and the identity block. This is the identification logic used on the product description side.

That matters when building a purchase order, drawing callout or catalogue entry, because the coded designation must be in the right order to identify the exact elbow.

Marking

Clause 5 requires marking according to EN 2424, style A, and Figure 1. The figure also identifies the area available for marking.

For production and inspection, this means the part must be marked in the aerospace marking style expected by the related standard, within the space reserved on the component.

Technical specification

Clause 6 states that the technical specification is EN 3275, type II. This links the elbow to the broader aerospace pipe-coupling technical rules used for qualification and acceptance.

What terms does SIST EN 4184:2004 define?

• Pipe coupling 8°30' - the coupling family used for this aerospace elbow, identified by the 8°30' geometry.
• Welded ends - ends intended to be joined by welding rather than by threaded or flared connection methods.
• Nominal pressure - the pressure rating used for selection and application of the part family.
• Surface roughness - the controlled finish condition called up by Figure 1 unless design documentation changes it.
• Type II - the EN 3275 acceptance category used when unspecified dimensions are left to manufacturer choice.
• Style A - the marking style required by EN 2424.
• TI-P64001 - the titanium alloy designation used in the referenced material standards for this product family.

Who uses SIST EN 4184:2004?

SIST EN 4184:2004 is used by aerospace fluid system designers who need a defined elbow geometry for 8°30' titanium alloy pipe couplings. It is also used by manufacturers, machining and forging suppliers, and welding shops that need the required dimensions, material condition and marking rules.

Quality and inspection teams use it to check conformance to Figure 1, Table 1, the surface finish callout, the material standards and the marking requirement. Buyers and supply-chain staff use it to specify the exact coded part and confirm that the offered item matches the aerospace coupling family.

Which standards are used with SIST EN 4184:2004?

• EN 2424 - gives the aerospace product marking rules, including style A.
• EN 2656 - defines the geometric configuration of welded coupling ends and the code to pressure-class relationship.
• EN 3275 - provides the technical specification, including qualification and acceptance type II.
• EN 3311 - specifies titanium alloy TI-P64001, annealed, bar for machining.
• EN 3312 - specifies titanium alloy TI-P64001, grade 2, annealed, forgings.
• EN 3314 - specifies titanium alloy TI-P64001, solution treated and aged, bar for machining.
• EN 3315 - specifies titanium alloy TI-P64001, solution treated and aged, forgings.

What does the SIST EN 4184:2004 document contain?

The document contains the scope, normative references and the required characteristics for the elbow family. Figure 1 shows the configuration and marking area, while Table 1 lists the coded sizes together with the corresponding dimensions and mass.

It also contains the designation note, the marking rule and the statement that EN 3275, type II, is the technical basis. For users, the document is mainly a product definition sheet for specification, procurement, manufacturing and acceptance of a standardized aerospace elbow.

SLOVENSKI STANDARD
01-maj-2004
Aerospace series - Pipe coupling 8°30' in titanium alloy - Elbows 45° double,
welded ends
Aerospace series - Pipe coupling 8°30' in titanium alloy - Elbows 45° double, welded
ends
Luft- und Raumfahrt - Rohrverschraubung 8°30' aus Titanlegierung -
Winkelverschraubungen 45° mit Anschweißenden
Série aérospatiale - Systeme de raccordement 8°30' en alliage de titane - Raccords
coudés a 45° doubles, a souder
Ta slovenski standard je istoveten z: EN 4184:2001
ICS:
49.080 /HWDOVNLLQYHVROMVNL Aerospace fluid systems and
KLGUDYOLþQLVLVWHPLLQGHOL components
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN 4184
NORME EUROPÉENNE
EUROPÄISCHE NORM
October 2001
ICS 49.080
English version
Aerospace series - Pipe coupling 8°30' in titanium alloy - Elbows
45°, welded ends
Série aérospatiale - Système de raccordement 8°30' en Luft- und Raumfahrt - Rohrverschraubung 8°30' aus
alliage de titane - Raccords coudés à 45°, à souder Titanlegierung - Winkelverschraubungen 45° mit
Anschweißenden
This European Standard was approved by CEN on 28 February 2001.
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 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 Management Centre has the same status as the official
versions.
CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece,
Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36  B-1050 Brussels
© 2001 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 4184:2001 E
worldwide for CEN national Members.

Foreword
This European Standard has been prepared by the European Association of Aerospace Manufacturers (AECMA).
After inquiries 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 AECMA, 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 April 2002, and conflicting national standards shall be withdrawn at the latest by April 2002.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are
bound to implement this European Standard: Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany,
Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United
Kingdom.
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