SIST EN 4493:2008

Aerospace series - Inserts, screw thread, helical coil, self-locking, in heat resisting nickel base alloy NI-PH1801 (NI-P96HT, Nimonic 90), silver plated

This standard specifies the characteristics of self-locking, helical coil, screw thread inserts in NI-PH1801 (NI P96HT), silver plated, for aerospace applications.
Maximum test temperature: 550 °C.

Luft- und Raumfahrt - Draht-Gewindeeinsätze, selbstsichernd, aus hochwarmfester Nickelbasislegierung NI-PH1801 (NI-P96HT, Nimonic 90), versilbert

Diese Norm legt die Eigenschaften von selbstsichernden Draht Gewindeeinsätzen aus NI PH1801 (NI P96HT), versilbert, für die Anwendung in der Luft- und Raumfahrt fest.
Maximale Prüftemperatur: 550 °C.

Série aérospatiale - Filets rapportés, à freinage interne, en alliage résistant à chaud à base de nickel NI-PH1801 (NI-P96HT, Nimonic 90), argentés

Aeronavtika - Vložki s spiralnim navojem, samozapiralni, iz zlitine, odporne proti toploti, na nikljevi osnovi NI-PH1801 (NI-P96HT, Nimonic 90), posrebreni

General Information

• Status: Published
• Publication Date: 26-May-2008
• ICS: 49.030.10 - Screw threads
• Technical Committee: I13 - Imaginarni 13
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 09-May-2008
• Due Date: 14-Jul-2008
• Completion Date: 27-May-2008
• Ref Project: EN 4493:2008 - Aerospace series - Inserts, screw thread, helical coil, self-locking, in heat resisting nickel base alloy NI-PH1801 (NI-P96HT, Nimonic 90), silver plated

Overview

SIST EN 4493:2008 is a European Standard published by CEN that specifies self-locking, helical coil screw thread inserts made from the heat-resistant nickel base alloy NI-PH1801 (also known as NI-P96HT or Nimonic 90). These inserts are silver plated to enhance durability and conductivity, primarily designed for aerospace applications requiring high performance under elevated temperatures. The standard ensures reliability and safety of threaded fastener systems operating up to 550 °C, essential for aerospace component integrity.

This standard covers detailed requirements including material properties, dimensions, tolerances, surface treatments, marking, and designation to maintain consistent quality across aerospace manufacturing and maintenance processes.

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Key Topics

• Material Specification: Uses NI-PH1801 alloy which offers excellent heat resistance, mechanical strength, and corrosion resistance, standardized by EN 2400.
• Surface Treatment: Electrolytic silver plating applied in thickness from 2 µm to 5 µm, defined under EN 2786, to provide improved conductivity and resistance to oxidation.
• Design and Dimensions: Precise dimensional tolerances and configurations are specified to meet aerospace thread compatibility. Dimensions conform to ISO 5855-2 where applicable.
• Self-Locking Feature: Inserts incorporate a specially designed locking coil section to resist loosening under vibration and thermal cycling, critical for aerospace fastener security.
• Marking and Designation: Standardized marking per EN 2424 ensures traceability and identification of thread inserts during assembly and inspections.
• Test Conditions: Inserts are tested at temperatures up to 550 °C to simulate demanding aerospace environments.

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Applications

SIST EN 4493:2008 compliant inserts are widely used across the aerospace sector for:

• Aircraft Engines and Airframes: Where fasteners face high temperatures and require resistance to thermal expansion and stress.
• Spacecraft Components: Heat-resisting properties suit inserts used in space vehicles and satellites.
• High-Performance Mechanical Assemblies: Wherever secure screw thread engagement and self-locking are critical under extreme temperature conditions.
• Maintenance and Repairs: Standardized inserts enable reliable replacement parts conforming to aerospace quality and safety demands.

Use of EN 4493 thread inserts guarantees longevity and secure fastening in critical aerospace assemblies, minimizing risks of fastener failure due to temperature stress or vibration-induced loosening.

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Related Standards

• EN 2400: Specifies heat resisting nickel base alloy NI-P96HT wire properties used for making these inserts.
• EN 2786: Defines the electrolytic silver plating process on fasteners for corrosion and conductivity benefits.
• EN 2943: Provides the technical specifications for self-locking, helical coil screw thread inserts more broadly.
• EN 2945: Details assembly procedures for installing these inserts correctly.
• EN 3044: Covers design standards for installation holes to accommodate such coil inserts.
• EN 2424: Aerospace series marking standards for traceability of aerospace products.
• ISO 5855-2: International standard for limit dimensions on aerospace bolts and nuts that interface with these inserts.

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SIST EN 4493:2008 supports aerospace manufacturers and suppliers in delivering high-reliability threaded fastening solutions specifically engineered for extreme heat conditions. By aligning with this standard, stakeholders ensure compliance with stringent aerospace performance criteria, operational safety, and maintenance efficiency.

Standards Content (Sample)

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Aerospace series - Inserts, screw thread, helical coil, self-locking, in heat resisting nickel base alloy NI-PH1801 (NI-P96HT, Nimonic 90), silver platedAeronavtika - Vložki s spiralnim navojem, samozapiralni, iz zlitine, odporne proti toploti, na nikljevi osnovi NI-PH1801 (NI-P96HT, Nimonic 90), posrebreniSérie aérospatiale - Filets rapportés, à freinage interne, en alliage résistant à chaud à base de nickel NI-PH1801 (NI-P96HT, Nimonic 90), argentésLuft- und Raumfahrt - Draht-Gewindeeinsätze, selbstsichernd, aus hochwarmfester Nickelbasislegierung NI-PH1801 (NI-P96HT, Nimonic 90), versilbert49.030.10NavojiScrew threadsICS:SIST EN 4493:2008enTa slovenski standard je istoveten z:EN 4493:200801-julij-2008SIST EN 4493:2008SLOVENSKI
STANDARD
EUROPEAN STANDARDNORME EUROPÉENNEEUROPÄISCHE NORMEN 4493April 2008ICS 49.030.10 English VersionAerospace series - Inserts, screw thread, helical coil, self-locking, in heat resisting nickel base alloy NI-PH1801 (NI-P96HT, Nimonic 90), silver platedSérie aérospatiale - Filets rapportés, à freinage interne, enalliage résistant à chaud à base de nickel NI-PH1801 (NI-P96HT, Nimonic 90), argentésLuft- und Raumfahrt - Draht-Gewindeeinsätze,selbstsichernd, aus hochwarmfester NickelbasislegierungNI-PH1801 (NI-P96HT, Nimonic 90), versilbertThis European Standard was approved by CEN on 29 February 2008.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application to the CEN 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 translationunder the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as theofficial versions.CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMITÉ EUROPÉEN DE NORMALISATIONEUROPÄISCHES KOMITEE FÜR NORMUNGManagement Centre: rue de Stassart, 36
B-1050 Brussels© 2008 CENAll rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 4493:2008: E
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