NAS 1801 Hex Head Screws

NAS 1801 is a high-strength hex head screw designed for demanding aerospace and high-performance industrial applications. It features a cruciform recess with a full-thread design, providing reliable fastening, excellent torque transfer, and uniform load distribution.

Manufactured in accordance with Aerospace Standard (NAS) specifications, NAS 1801 fasteners ensure consistent performance in critical assemblies where strength and precision are essential.

NAS 1801 Specifications

Standard: NAS 1801
Fastener Type: Hex Head Screw
Recess Type: Cruciform Recess
Thread Type: Full Thread
Material: Alloy Steel
Minimum Tensile Strength: 160 KSI (Ftu)
Equivalent Materials: AISI 4140 / 4340 / 8740

These screws are engineered to deliver high mechanical strength, excellent fatigue resistance, and dependable performance under high loads.

Key Features Of NAS 1801 Hex Head Screws

High-strength alloy steel construction
160 KSI tensile strength for critical load applications
Excellent fatigue and wear resistance
Hex head design for secure torque application
Cruciform recess for controlled installation
Full thread for strong and uniform clamping force

Applications OF NAS 1801

NAS 1801 fasteners are widely used in:

Aircraft Engines and Mechanical Assemblies
Defense and Military Equipment
High-Performance Industrial Machinery

Why Choose NAS 1801 from UPS Lakshmi?

With over 65 years of manufacturing expertise, UPS Lakshmi is a trusted supplier of aerospace and precision fasteners worldwide.

Strict quality control and inspection
Aerospace-standard manufacturing processes
High dimensional accuracy and consistency
Reliable performance in critical operating conditions
Custom sizes and bulk supply available

Frequently Asked Questions About NAS1801 Screws

What is a NAS1801 screw?

NAS1801 is a National Aerospace Standard that covers fully threaded socket head cap screws designed for demanding aerospace assemblies. These fasteners use a hex socket drive and a precise thread form. The standard defines dimensions, materials, and strength so that each screw performs reliably in flight-critical and high-load joints.

Which materials are NAS1801 screws made from?

These screws are typically produced from alloy steel for high tensile strength or from A286 corrosion-resistant steel for heat and oxidation resistance. Material choice depends on load, temperature, and the operating environment. A286 suits hot zones and corrosive environments, while alloy steel is suited to strength-led structural work.

How do NAS1801 screws differ from standard socket cap screws?

NAS1801 screws meet tighter aerospace tolerances, controlled material grades, and traceable quality records that commercial fasteners rarely match. The fine-thread form and consistent head dimensions support reliable preload in vibration-heavy assemblies. This control reduces the risk of joint slip, fatigue, and unexpected failure in service.

Where are NAS1801 screws commonly used?

They appear across airframe structures, engine mounts, control systems, and other assemblies where strength and reliability are non-negotiable. The fully threaded body gives a strong grip in tapped holes and thick sections. Engineers select them for joints that face cyclic loads, vibration, and strict safety certification demands.