ASME · ANSI / ASME B18.31.3

ANSI/ASME B18.31.3 Standard: Inch-Series Threaded Rods — Technical Overview

Technical Specification and Scope of the ANSI/ASME B18.31.3 Standard

This regulatory document establishes comprehensive requirements for the geometric parameters and general characteristics of inch-series threaded rods that comply with the standards of the American National Standards Institute (ANSI). EV Group China supplies high-quality fasteners covering a diameter range from 1/4 to 4 inches, including UNC, UNF, 8UN, and ACME thread types. The product range includes both right-hand and left-hand threaded items to address specialized engineering challenges.

It is important to note that, currently, the international ISO standards system does not contain equivalent specifications for inch-series threaded rods, making the ASME B18.31.3 standard the baseline for design and procurement in this segment.

The technical data presented in the standard is for reference purposes and defines design tolerances. For details regarding the availability of specific sizes in EV Group China's stock and serial production volumes, it is recommended to send individual inquiries to our technical specialists.

Dimensional Grid and Tolerances

All metric values within this standard are presented in the imperial system (inches), unless otherwise specified in the product specification.

Terminology Base

The definitions and classification of terms used in the production and acceptance of products fully comply with the current edition of the ASME B18.12 standard. All references to related standards imply the use of their latest valid versions at the time of order placement with EV Group China.