SIST EN 2862:2010

Overview

SIST EN 2862:2010 is a European aerospace standard specifying the requirements for anchor nuts used in critical aerospace applications. These nuts feature a self-locking mechanism achieved by an out-of-round upper portion, fixed at a 90° corner with a counterbore design. Manufactured from alloy steel, they are cadmium plated and lubricated with molybdenum disulphide (MoS2), ensuring durability and resistance under specific mechanical and thermal conditions.

Classified for a strength of 1,100 MPa at ambient temperature and capable of withstanding temperatures up to 235 °C, this standard ensures high performance, safety, and reliability in aerospace fastening systems.

Key Topics

• Self-Locking Anchor Nuts
  These nuts prevent loosening under vibration and stress through a mechanical self-locking feature formed by deforming the upper section out-of-round.

• Material and Surface Treatment
  Nuts are made from heat-treated alloy steel conforming to EN 2542 and EN 2543, cadmium plated according to EN 2133 for corrosion resistance, and coated with MoS2 lubricant following EN 2491 standards for enhanced friction control.

• Dimensions and Tolerances
  The configuration aligns with ISO 3221 dimensions, covering various thread sizes (MJ3 to MJ10) with strict form and position tolerances as per ISO 8788, guaranteeing interchangeability and precision fit.

• Temperature and Strength Classification
  The nuts are rated at 1100 MPa tensile strength at room temperature and maintain integrity up to 235 °C, suitable for aerospace environmental demands.

• Marking and Identification
  Compliant with EN 2424, ensuring traceability and correct application, including options for plain or dimpled/countersunk rivet holes.

• Quality and Certification
  Manufactured under strict quality management systems such as EN 9100 and qualified per EN 9133, ensuring consistent quality and compliance with aerospace industry requirements.

Applications

SIST EN 2862:2010 nuts are critical components in aerospace assembly where fasteners must resist vibration, thermal cycling, and mechanical loads without loosening or failure. Typical applications include:

• Aircraft Structural Assemblies
  Used for securing panels, frames, and structural components requiring reliable fastener locking.

• Engine and Airframe Components
  Suitable for joints subjected to high temperatures and mechanical stress.

• Spacecraft and Defense Systems
  Ideal for aerospace and defense equipment demanding strict safety and material standards.

• Maintenance and Repair Operations
  Replacement and retrofitting components maintaining compliance with aerospace quality and compatibility criteria.

Related Standards

SIST EN 2862:2010 works in conjunction with several international and European standards to cover material, dimension, and quality aspects, such as:

• EN 2133 - Cadmium plating of steels, ensuring corrosion protection necessary for aerospace parts.
• EN 2424 - Marking of aerospace products for product traceability.
• EN 2491 - Coating methods for MoS2 lubrication, critical for reducing friction.
• ISO 3221 - Dimension standards for aerospace anchor nuts with self-locking features.
• ISO 5855-2 and ISO 8788 - Thread and tolerance specifications for aerospace nuts and bolts.
• EN 9100 and EN 9133 - Quality management systems and qualification procedures tailored for aerospace standard parts.

This network of standards ensures that EN 2862 nuts meet rigorous performance, safety, and compatibility requirements within aerospace manufacturing and maintenance contexts.

Keywords: EN 2862 standard, aerospace anchor nuts, self-locking nuts, cadmium plated nuts, MoS2 lubrication, aerospace fasteners, 1,100 MPa nuts, aerospace nuts ISO 3221, aerospace nut dimensions, aerospace quality management, aerospace standard nuts, 90° corner nuts, aerospace counterbored nuts.