SAE MA1937A-2018 PDF

Full title and description

SAE MA1937A-2018 — Nut, Hex, Free Running, Procurement Specification For, Metric. This procurement specification defines requirements for alloy steel and corrosion- and heat-resistant steel free-running metric hex nuts, including types, styles and classes used in aerospace applications.

Abstract

MA1937A provides procurement, material, dimensional and quality requirements for metric hexagon free-running nuts intended for aerospace and propulsion-system use. The document identifies applicable reference standards, technical requirements, inspection and acceptance criteria, and delivery preparation provisions for these fasteners.

General information

• Status: Stabilized.
• Publication date: January 29, 2018 (Stabilized edition MA1937A).
• Publisher: SAE International (Society of Automotive Engineers).
• ICS / categories: Fasteners — Nuts (ICS 21.060.20).
• Edition / version: MA1937A (revision/stabilized edition replacing MA1937:2012).
• Number of pages: 14 pages.

Scope

This procurement specification covers alloy steel and corrosion- and heat-resistant steel free-running metric hex nuts of specified types, styles and classes used primarily in aerospace propulsion and related systems. It establishes material and dimensional requirements, inspection and test provisions, quality assurance and preparation-for-delivery instructions for suppliers and procuring activities.

Key topics and requirements

• Definition of nut types, styles and classes (metric hexagon free-running nuts).
• Material requirements for alloy steel and corrosion/heat‑resistant steels.
• Dimensional and thread gaging requirements, referencing applicable metric thread standards and SAE gaging practices.
• Technical requirements covering mechanical properties, surface condition and finish.
• Quality assurance provisions including inspection, sampling, non‑destructive testing and rejection criteria.
• Preparation for delivery, marking and documentation requirements for procurement acceptance.
• List of applicable/reference documents (SAE AMS/MA documents, ASTM/MIL/AS standards and related thread/fastener standards).

Typical use and users

Used by aerospace manufacturers, propulsion-system component suppliers, fastener producers, procurement engineers, quality assurance and inspection teams, and maintenance organizations that require procurement specifications for metric hex nuts in aerospace applications. It is typically applied when ordering or qualifying free-running metric hex nuts for aircraft and engine hardware.

Related standards

MA1937A references and is used alongside related SAE and industry standards such as SAE MA1566A (gaging practice for MJ metric screw threads), SAE AMS and AS documents for materials and inspection, and common ASTM/MIL standards cited in the applicable documents list. It replaces and supersedes earlier MA1937 editions (2012 and prior).

Keywords

SAE MA1937A, nut, hex nut, free running, metric, procurement specification, aerospace fastener, alloy steel, corrosion resistant, heat resistant, gaging, inspection.

FAQ

Q: What is this standard?

A: SAE MA1937A-2018 is a procurement specification for metric hexagon free-running nuts used in aerospace applications, defining material, dimensional, inspection and delivery requirements.

Q: What does it cover?

A: It covers alloy steel and corrosion- and heat‑resistant steel free-running metric hex nuts of specified types, styles and classes, plus related quality, testing, gaging and delivery requirements for procurement.

Q: Who typically uses it?

A: Aerospace manufacturers, fastener suppliers, procurement and quality engineers, and maintenance/overhaul organizations that need a standardized procurement/specification for metric hex nuts.

Q: Is it current or superseded?

A: The MA1937A edition was published and stabilized January 29, 2018 and is listed as the stabilized (current) edition replacing earlier MA1937 releases. Confirm current status with SAE International for any amendments after 2018.

Q: Is it part of a series?

A: Yes — MA standards are part of SAE’s Aerospace (MA) series addressing fasteners, gaging and related hardware standards; MA1937A is related to other MA and AMS documents referenced within its applicable documents section.

Q: What are the key keywords?

A: Nut, hex, free running, metric, procurement specification, aerospace, alloy steel, corrosion resistant, heat resistant, gaging, inspection.