SIST EN 1092-1:2018
(Main)Flanges and their joints - Circular flanges for pipes, valves, fittings and accessories, PN designated - Part 1: Steel flanges
Flanges and their joints - Circular flanges for pipes, valves, fittings and accessories, PN designated - Part 1: Steel flanges
This European Standard for a single series of flanges specifies requirements for circular steel flanges in PN designations PN 2,5 to PN 400 and nominal sizes from DN 10 to DN 4000.
This European Standard specifies the flange types and their facings, dimensions, tolerances, threading, bolt sizes, flange jointing face surface finish, marking, materials, pressure/ temperature ratings and approximate flange masses.
For the purpose of this European Standard, "flanges" include also lapped ends and collars.
This European Standard applies to flanges manufactured in accordance with the methods described in Table 1.
Non-gasketed pipe joints are outside the scope of this European Standard.
Flansche und ihre Verbindungen - Runde Flansche für Rohre, Armaturen, Formstücke und Zubehörteile, nach PN bezeichnet - Teil 1: Stahlflansche
Brides et leurs assemblages - Brides circulaires pour tubes, appareils de robinetterie, raccords et accessoires, désignées PN - Partie 1 : Brides en acier
La présente Norme européenne pour un seul système de brides spécifie les prescriptions pour les brides circulaires en acier avec les désignations PN 2,5 à PN 400 et les diamètres nominaux DN 10 à DN 4000.
La présente Norme européenne définit les types de brides et leurs portées de joint, les dimensions, les tolérances, les filetages, les dimensions des boulons, les états de surface des faces de joints des brides, le marquage, les matériaux, les relations pression/température et les masses approximatives des brides.
Pour les besoins de la présente Norme européenne, le terme « brides » inclut aussi les collets et les extrémités embouties à souder.
La présente Norme européenne s'applique aux brides fabriquées selon les méthodes décrites au
Tableau 1.
Les assemblages de tuyauteries sans joints se trouvent hors du domaine d'application de la présente Norme européenne.
Prirobnice in prirobnični spoji - Okrogle prirobnice za cevi, ventile, fitinge in pribor z oznako PN - 1. del: Jeklene prirobnice
Ta osnutek evropskega standarda za posamezni niz prirobnic določa zahteve za okrogle jeklene prirobnice z oznakami PN od PN 2,5 do PN 400 in nominalno velikostjo od DN 10 do DN 4000.
Ta osnutek evropskega standarda določa vrste prirobnic in njihove prevleke, mere, tolerance, navoje, velikosti vijakov, površinski premaz stične ploskve prirobnice, označevanje, materiale, vrednosti tlaka/temperature in približne mase prirobnic.
Za namene tega osnutka evropskega standarda »prirobnice« vključujejo tudi preklopljene konce in obroče.
Ta osnutek evropskega standarda velja za prirobnice, proizvedene v skladu z metodami, opisanimi v preglednici 1.
Spoji cevi brez tesnil ne spadajo v področje uporabe tega osnutka evropskega standarda.
General Information
- Status
- Published
- Public Enquiry End Date
- 04-Jun-2016
- Publication Date
- 11-Jun-2018
- Technical Committee
- TLP - Pressure vessels
- Current Stage
- 6060 - National Implementation/Publication (Adopted Project)
- Start Date
- 22-Mar-2018
- Due Date
- 27-May-2018
- Completion Date
- 12-Jun-2018
Relations
- Effective Date
- 01-Jul-2018
- Effective Date
- 01-Jul-2018
- Effective Date
- 01-Dec-2022
Overview
SIST EN 1092-1:2018 - "Flanges and their joints - Circular flanges for pipes, valves, fittings and accessories, PN designated - Part 1: Steel flanges" is the European standard that specifies requirements for circular steel flanges in PN designations PN 2,5 to PN 400 and nominal sizes DN 10 to DN 4000. The standard covers flange types, facings, dimensions, tolerances, threading, bolt sizes, surface finishes, marking, materials, p/T (pressure/temperature) ratings, and approximate flange masses. It also includes lapped ends and collars and applies to flanges manufactured by the methods referenced in the standard (see Table 1). Non‑gasketed pipe joints are excluded.
Key Topics and Requirements
- Scope and designation: Defines PN-based designation and DN size ranges for a single flange series.
- Flange types & facings: Specifies standardized flange types and jointing face styles (e.g., raised face, flat face, grooves).
- Dimensions & tolerances: Normative dimensions for mating, bolt holes, hubs, collars and limits for manufacturing tolerances.
- Materials & manufacturing: Requirements for base materials, permitted manufacture methods, and welding/repair provisions.
- Bolting & threading: Standard bolt sizes, thread specifications and bolt‑hole patterns for reliable joint integrity.
- Gaskets & jointing surface finish: Surface finish requirements for flange faces and guidance for gasket selection and seating.
- Pressure/temperature (p/T) ratings: Methodology and annexed tables to determine allowable pressure at temperature for listed EN materials (see normative Annexes F and G).
- Marking, inspection & testing: Mandatory marking, stamping, certificates and inspection/testing rules (including welding inspection).
- Ancillary information: Annexes include flange mass tables, calculation basis (Annex E), p/T calculation rules and examples, and material group guidance.
Practical Applications and Users
SIST EN 1092-1:2018 is intended for designers, manufacturers and users of pressure piping systems across industries such as oil & gas, petrochemical, water treatment, power generation and HVAC. Typical use cases:
- Specifying flange components for new piping systems and valve connections.
- Procurement and quality inspection of manufactured flanges and collars.
- Engineering calculations for flange joints (bolting, gasket selection and p/T ratings).
- Ensuring compliance with the EU Pressure Equipment Directive (informative Annex ZA).
Primary users: mechanical and piping engineers, flange and valve manufacturers, fabricators, inspection bodies, procurement teams and standards compliance officers.
Related Standards
- EN 1092 series: Part 2 (Cast iron flanges), Part 3 (Copper alloy flanges), Part 4 (Aluminium alloy flanges).
- ISO 7005 series (historical basis - EN 1092-1 focuses on PN‑based flanges).
- EU Directive 2014/68/EU (Pressure Equipment Directive) - Annex ZA provides relationship to essential requirements.
Keywords: SIST EN 1092-1:2018, steel flanges, PN designated flanges, circular flanges, flange facings, p/T ratings, flange dimensions, flange tolerances, flange marking.
Frequently Asked Questions
SIST EN 1092-1:2018 is a standard published by the Slovenian Institute for Standardization (SIST). Its full title is "Flanges and their joints - Circular flanges for pipes, valves, fittings and accessories, PN designated - Part 1: Steel flanges". This standard covers: This European Standard for a single series of flanges specifies requirements for circular steel flanges in PN designations PN 2,5 to PN 400 and nominal sizes from DN 10 to DN 4000. This European Standard specifies the flange types and their facings, dimensions, tolerances, threading, bolt sizes, flange jointing face surface finish, marking, materials, pressure/ temperature ratings and approximate flange masses. For the purpose of this European Standard, "flanges" include also lapped ends and collars. This European Standard applies to flanges manufactured in accordance with the methods described in Table 1. Non-gasketed pipe joints are outside the scope of this European Standard.
This European Standard for a single series of flanges specifies requirements for circular steel flanges in PN designations PN 2,5 to PN 400 and nominal sizes from DN 10 to DN 4000. This European Standard specifies the flange types and their facings, dimensions, tolerances, threading, bolt sizes, flange jointing face surface finish, marking, materials, pressure/ temperature ratings and approximate flange masses. For the purpose of this European Standard, "flanges" include also lapped ends and collars. This European Standard applies to flanges manufactured in accordance with the methods described in Table 1. Non-gasketed pipe joints are outside the scope of this European Standard.
SIST EN 1092-1:2018 is classified under the following ICS (International Classification for Standards) categories: 23.040.60 - Flanges, couplings and joints. The ICS classification helps identify the subject area and facilitates finding related standards.
SIST EN 1092-1:2018 has the following relationships with other standards: It is inter standard links to SIST EN 1092-1:2007+A1:2013/AC:2014, SIST EN 1092-1:2007+A1:2013, SIST EN 1092-1:2018/oprA1:2022. Understanding these relationships helps ensure you are using the most current and applicable version of the standard.
SIST EN 1092-1:2018 is associated with the following European legislation: EU Directives/Regulations: 2014/68/EU, 2014/90/EU, 88/379/EEC, 97/23/EC, EUR-PUB; Standardization Mandates: M/071, M/109. When a standard is cited in the Official Journal of the European Union, products manufactured in conformity with it benefit from a presumption of conformity with the essential requirements of the corresponding EU directive or regulation.
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Standards Content (Sample)
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Flansche und ihre Verbindungen - Runde Flansche für Rohre, Armaturen, Formstücke und Zubehörteile, nach PN bezeichnet - Teil 1: StahlflanscheBrides et leurs assemblages - Brides circulaires pour tubes, appareils de robinetterie, raccords et accessoires, désignées PN - Partie 1 : Brides en acierFlanges and their joints - Circular flanges for pipes, valves, fittings and accessories, PN designated - Part 1: Steel flanges23.040.60Prirobnice, oglavki in spojni elementiFlanges, couplings and jointsICS:Ta slovenski standard je istoveten z:EN 1092-1:2018SIST EN 1092-1:2018en,fr,de01-julij-2018SIST EN 1092-1:2018SLOVENSKI
STANDARDSIST EN 1092-1:2007+A1:2013/AC:2014SIST EN 1092-1:2007+A1:20131DGRPHãþD
EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM
EN 1092-1
April
t r s z ICS
t uä r v rä x r Supersedes EN
s r { tæ sã t r r y ªA sã t r s uEnglish Version
Flanges and their joints æ Circular flanges for pipesá valvesá fittings and accessoriesá PN designated æ Part
sã Steel flanges Brides et leurs assemblages æ Brides circulaires pour tubesá appareils de robinetterieá raccords et accessoiresá désignées PN æ Partie
sã Brides en acier
Flansche und ihre Verbindungen æ Runde Flansche für Rohreá Armaturená Formstücke und Zubehörteileá nach PN bezeichnet æ Teil
sã Stahlflansche This European Standard was approved by CEN on
t y November
t r s yä
egulations which stipulate the conditions for giving this European Standard the status of a national standard without any alterationä Upætoædate lists and bibliographical references concerning such national standards may be obtained on application to the CENæCENELEC Management Centre or to any CEN memberä
translation under the responsibility of a CEN member into its own language and notified to the CENæCENELEC Management Centre has the same status as the official versionsä
CEN members are the national standards bodies of Austriaá Belgiumá Bulgariaá Croatiaá Cyprusá Czech Republicá Denmarká Estoniaá Finlandá Former Yugoslav Republic of Macedoniaá Franceá Germanyá Greeceá Hungaryá Icelandá Irelandá Italyá Latviaá Lithuaniaá Luxembourgá Maltaá Netherlandsá Norwayá Polandá Portugalá Romaniaá Serbiaá Slovakiaá Sloveniaá Spainá Swedená Switzerlandá Turkey and United Kingdomä
EUROPEAN COMMITTEE FOR STANDARDIZATION COMITÉ EUROPÉEN DE NORMALISATION EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre:
Rue de la Science 23,
B-1040 Brussels
t r s z CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Membersä Refä Noä EN
s r { tæ sã t r s z ESIST EN 1092-1:2018
Wall thickness and end preparation for flanges type 11, 34, 35, 36, 37 and pipe nominal thicknesses for the use with type 01 flanges . 83 A.1 Weld-end preparation for flanges types 11 and 34 . 83 A.2 Weld-end preparation for type 35 . 85 A.3 Weld end preparation for types 36 and 37 . 87 Annex B (informative)
Material groups . 89 Annex C (informative)
Approximate masses of flanges and collars . 91 Annex D (informative)
Additional materials . 101 Annex E (normative)
Basis of flange calculation . 103 E.1 General . 103 E.2 Calculation method . 103 E.3 Basic rules for calculation of flange connection . 103 E.3.1 General . 103 E.3.2 Flanges . 104 E.3.3 Pipes . 104 E.3.4 Bolting/Tightening. 105 E.3.5 Gasket . 105 Annex F (normative)
Determination of p/T ratings . 107 F.1 General . 107 F.1.1 Reference temperature (RT) . 107 F.1.2 Application limits and formulae . 107 F.2 Symbols, descriptions and units. 107 F.2.1 General . 107 F.2.2 p/T ratings for materials with time independent nominal design stress . 108 F.2.3 p/T ratings for materials with time dependent nominal design stress . 108 F.2.4 Reference value for thickness (vR) . 108 F.2.5 Nominal design stresses and safety factors for mean creep rupture strength . 108 F.2.6 Flanges made from steel castings . 109 F.2.7 Rounding of maximum allowable pressure at temperature . 109 Annex G (normative)
p/T ratings for a selection of EN materials . 110 G.1 General . 110 G.1.1 p/T ratings . 110 G.1.2 Basics of determination of p/T ratings (see Annex F) . 110 G.1.3 Application limits for creep range . 110 G.2 Non-austenitic steels . 111 G.2.1 General . 111 G.2.2 List of materials . 112 SIST EN 1092-1:2018
Rings for flanges with groove . 138 Annex I (informative)
Flanges with fixed inner diameter . 139 I.1 General . 139 I.2 Scope . 139 Annex J (informative)
Mating dimensions for flanges with higher DN . 144 Annex ZA (informative)
Relationship between this European Standard and the Essential Requirements of EU Directive 2014/68/EU Pressure Equipment Directive aimed to be covered . 146 Bibliography . 147
electric welded form bars, sectional steel or strip b, c, d, e Pressed from welded or seamless pipes or flat products 01 (Plate flange for welding) yes no yes yes yes no 02 (Loose plate flange for Types 32—37) yes no yes yes yes no 04 (Loose plate flange for Type 34) yes no yes yes yes no 05 (Blind flange) yes no yes yes no no 11 (Weld-neck flange) yes no no yes yes, for
· DN 700 no 12 (Hubbed slip-on flange for welding) yes no no yes no no 13 (Hubbed threaded flange) yes no no yes no no 21 (Integral flange) yes yes no yes no no 32 (Weld-on plate collar) yes no yes yes yes no 33 (Lapped end pipe) yes no yes no yes yes 34 (Weld-neck collar) yes yes no yes yes no 35 (Welding neck) yes no yes yes yes no 36 (Pressed collar with long neck) yes no no no yes yes 37 (Pressed collar) yes no yes yes yes yes
a Seamless rolled, pressed, forged.
b Only one radial weld is allowed under DN 1800. If using cut strips for manufacturing, the through thickness direction of the strip for type 11 and 34 shall be perpendicular to the flange centerline, for Type 01, 02, 04 and 32 in the direction of the flange centreline.
c For welding: see 5.11.
d Welded flanges allowed only for an application up to 370 °C in conformance with EN 13480–3:2002, D.4.4.
e In case flanges are made by cold forming of a base material e.g. flat product, some mechanical properties, like elongation after fracture (A) and impact energy (KV), will be impaired due to cold forming without subsequently heat treatment. 5.2 Repairs by welding With the exception of weld repairs according to 5.11 repairs by welding are permitted only by written agreement of the purchaser. Within the certificate for material or component relevant documents shall be noted, that approved welding procedure and welders qualification (see 5.11) have been applied. 5.3 Bolting Flanges shall be suitable for use with the number and size of bolting as specified in Table 10 to Table 21. The bolting shall be chosen by the equipment manufacturer according to the pressure, temperature, flange material and gasket so that the flanged joint remains tight under the expected operating SIST EN 1092-1:2018
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The SIST EN 1092-1:2018 standard provides comprehensive specifications for circular steel flanges used in various industrial applications. This European Standard effectively addresses flanges within the PN designations ranging from PN 2.5 to PN 400, encompassing nominal sizes from DN 10 to DN 4000. Its wide scope ensures that it caters to a vast array of industries requiring robust and reliable flange solutions. One of the key strengths of this standard is its detailed outline of various flange types and their facings, which aids manufacturers and users in selecting the appropriate flange for specific applications. By defining essential parameters such as dimensions, tolerances, threading, and bolt sizes, SIST EN 1092-1:2018 sets a clear framework for the production and utilization of steel flanges. This clarity promotes consistency in manufacturing processes, ultimately benefiting end-users in terms of performance and reliability. The standard also delves into critical aspects such as flange jointing face surface finish, marking requirements, materials, and pressure/temperature ratings. These specifications are vital for ensuring that flanges meet the necessary operational demands while maintaining safety and integrity under varying conditions. Furthermore, the inclusion of approximate flange masses aids in logistics and design calculations, making it a practical resource for engineers and designers. It is important to note that the standard includes not only traditional flanges but also lapped ends and collars, thereby expanding its applicability. However, it is explicitly stated that non-gasketed pipe joints are outside the scope of this standard, which helps clarify its specific focus and avoid any potential confusion. Overall, the SIST EN 1092-1:2018 standard plays a crucial role in standardizing the production and application of circular steel flanges, ensuring that they meet industry needs effectively and safely. Its clear definitions and specifications enhance its relevance across various sectors, making it a vital document for professionals engaged in the design, specification, and installation of piping systems.
Die SIST EN 1092-1:2018 stellt einen bedeutenden Standard für die Herstellung und Anwendung von Stahlflanschen dar, die in verschiedenen Bereichen wie Rohrleitungen, Armaturen und Zubehör eingesetzt werden. Der Geltungsbereich dieses Standards umfasst eine breite Palette von runden Flanschen mit PN-Bezeichnungen von PN 2,5 bis PN 400 sowie Nennweiten von DN 10 bis DN 4000. Diese Vielfalt macht den Standard für zahlreiche Anwendungen in der Industrie relevant. Ein zentraler Bestandteil der SIST EN 1092-1:2018 ist die präzise Festlegung der Flanschtypen sowie ihrer Flächen, Dimensionen und Toleranzen. Dies gewährleistet, dass die Flansche unter verschiedenen Betriebsbedingungen konsistent und zuverlässig sind. Der Standard definiert außerdem die Anforderungen an das Gewinde, die Größe der Bolzen, die Oberflächenbeschaffenheit der Flanschdichtung und die Kennzeichnung der Materialien. Die klaren Vorgaben zu Druck- und Temperaturgrenzwerten sowie zu den ungefähren Flanschmassen tragen dazu bei, die Sicherheit und Effizienz bei der Nutzung der Flansche zu erhöhen. Ein weiterer Vorteil des Standards liegt in seiner umfassenden Natur – nicht nur werden die wesentlichen Elemente von Flanschen behandelt, sondern auch die für die Fertigung verwendeten Methoden sind im Detail beschrieben. Die Möglichkeit, auch überlappten Enden und Kragen als Teil dieses Standards einzuschließen, zeigt die Flexibilität und Anpassungsfähigkeit der SIST EN 1092-1:2018 an die Bedürfnisse der Industrie. Die Relevanz dieses Standards kann nicht hoch genug eingeschätzt werden, da die korrekte Anwendung von Flanschen entscheidend für die Integrität und Sicherheit von Rohrleitungssystemen ist. Insbesondere in sicherheitskritischen Umgebungen, wo Druck und Temperatur eine Rolle spielen, sind die Vorgaben der SIST EN 1092-1:2018 von enormer Bedeutung. Darüber hinaus trägt die Standardisierung zu einem einheitlichen Verständnis und zur Qualitätssicherung in der Herstellung und Nutzung von Flanschen bei. Zusammenfassend lässt sich sagen, dass die SIST EN 1092-1:2018 ein unverzichtbares Dokument für Fachleute in der Branche ist, das die Grundlage für sichere und effiziente Anwendungen von Stahlflanschen bietet.
La norme SIST EN 1092-1:2018 offre un cadre essentiel pour la normalisation des joints et des flanges circulaires en acier, spécifiquement pour les tuyaux, vannes, raccords et accessoires, avec des désignations de PN allant de PN 2,5 à PN 400. Son champ d'application est particulièrement vaste, englobant des tailles nominales allant de DN 10 à DN 4000. Cette diversité permet d'assurer une large compatibilité et un usage dans divers contextes industriels. Parmi les points forts de cette norme, on note la spécification claire des types de flanges et leurs facings, ainsi que les dimensions, tolérances et tailles des boulons, éléments cruciaux pour garantir la sécurité et l’efficacité des systèmes de tuyauterie. La norme aborde également la finition de surface des faces de joint des flanches, ce qui contribue à améliorer la qualité des assemblages et à réduire le risque de fuites. De plus, les données concernant les matériaux, les classes de pression/température et les masses approximatives des flanges sont intégrées, rendant la norme encore plus utile pour les ingénieurs et les concepteurs. La pertinence de la norme SIST EN 1092-1:2018 repose sur son alignement avec les pratiques actuelles de fabrication et d'ingénierie, établissant ainsi un standard de référence pour la conception et l'utilisation des flanges en milieu industriel. En excluant les joints de tuyauterie non garnis du champ d'application, elle permet aussi de concentrer les efforts sur les applications les plus courantes et les plus critiques. En résumé, la norme SIST EN 1092-1:2018 est une ressource précieuse pour les professionnels du secteur, offrant des spécifications détaillées et une assurance de qualité pour les flanges circulaires en acier, contribuant ainsi à la sécurité et à l’efficacité des installations industrielles.
SIST EN 1092-1:2018は、パイプ、バルブ、フィッティングおよびアクセサリー用の円形フランジに関する欧州標準であり、特にPN指定の鋼製フランジに焦点を当てています。この標準は、PN 2.5からPN 400までの範囲およびDN 10からDN 4000までの名目サイズに対応する円形鋼フランジの要件を明確に定義しています。 この標準の強みとして、フランジの種類、面取り、寸法、許容差、ねじ、ボルトサイズ、フランジ接合面の表面仕上げ、マーキング、材料、圧力/温度定格、およびおおよそのフランジ質量が詳細に規定されている点が挙げられます。これにより、製造業者やエンジニアは、フランジの設計と製造プロセスにおいて、厳格な基準に従うことができ、一貫性と信頼性を確保することができます。 また、この標準は「フランジ」という用語をラップエンドやカラーにも適用しているため、適用範囲が広く、さまざまな工業用構造物における実用性が高まっています。さらに、フランジの製造方法が明確に示されているため、設計者やエンジニアは、製品の品質を確保しつつ、順守すべき要件を容易に理解できます。 ただし、ガスケットなしのパイプ接合はこの標準の適用範囲外であるため、ユーザーはそれを考慮に入れる必要があります。全体として、SIST EN 1092-1:2018は、鋼製フランジに関連する分野での実践的で重要な基準を提供しており、産業界における安全性と効率を促進する上で大変重要な役割を果たしています。
SIST EN 1092-1:2018 표준 문서는 파이프, 밸브, 피팅 및 액세서리에 사용되는 원형 강철 플랜지와 그 조인트에 관한 유럽 표준으로, PN 2.5에서 PN 400까지 그리고 DN 10에서 DN 4000까지의 공칭 크기를 포함하고 있습니다. 이 표준은 플랜지의 유형 및 면, 치수, 공차, 나사, 볼트 크기, 플랜지 조인트 면의 표면 마감, 표기, 재료, 압력/온도 등급 및 대략적인 플랜지 질량에 대한 요구 사항을 명확히 규정합니다. 이 표준의 범위는 플랜지 제조 방법을 Table 1에 명시된 대로 규정하고 있으며, '플랜지'는 겹쳐진 끝과 칼라도 포함하는 점이 특징입니다. SIST EN 1092-1:2018의 강점은 유럽 내에서 통일된 기준을 제공함으로써 산업에서의 안전성을 높이고, 다양한 응용 분야에서의 호환성을 보장한다는 것입니다. 이 문서가 갖는 중요성은 플랜지의 품질과 안전성을 보장하여, 설비의 신뢰성을 높이고 유지 보수 비용을 절감할 수 있는 기초를 마련한다는 것에 있습니다. 또한, 비가스켓형 파이프 조인트는 이 표준의 적용 범위에서 제외되므로, 사용자는 해당 표준을 활용할 때 더욱 명확한 기준을 갖고 선택할 수 있습니다. 이로 인해 이 표준은 산업계에서 매우 활용도가 높으며, 에너지 및 제조업 등 다양한 분야에서 그 필요성이 강조되고 있습니다.
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