TS EN 4591

TS EN 4591 is a standard for definitions, specifications and conformity criteria for self-locking, floating, self-aligning barrel nuts made from heat resisting nickel alloy and lubricated with MoS2. Despite the product record’s broader metadata, the technical subject here is a specialised fastener component, not building lime: a barrel nut designed for high-temperature and mechanically demanding assemblies.

What this fastener type is meant to do

A barrel nut is a captive-style nut form used with a mating screw or bolt, often where access is limited or alignment is difficult. The self-locking feature reflects the general engineering aim of resisting loosening under vibration and service movement. Floating and self-aligning behaviour helps the nut accommodate small positional errors during assembly, which can improve fit-up and load transfer. Using a heat resisting nickel alloy points to applications where elevated temperature performance matters, while MoS2 lubrication is commonly associated with reducing friction during tightening and assembly.

How the standard frames the product

The stated classification, 1 550 MPa / 315 °C, gives a combined strength-and-temperature designation for this product family. In practical terms, standards of this kind create a shared technical vocabulary for geometry, material description and acceptance criteria, so manufacturers and users can speak about the same fastener type with consistent expectations. The focus is on definition and conformity, rather than on a generic fastener overview.

• Self-locking, floating, self-aligning barrel nuts
• Heat resisting nickel alloy construction
• MoS2 lubricated
• Classification: 1 550 MPa / 315 °C
• Definitions, specifications and conformity criteria