The "butting principle" refers to a method of inspection where a measuring probe (or a master gear) contacts the tooth flank to evaluate deviations. Unlike coordinate measuring machines (CMMs) that scan surfaces, the butting method simulates how gears mesh in real operation.
The standard defines:
AGMA 218.01 (now obsolete) was a foundational standard for quantifying gear noise in enclosed drive systems. This paper reviews the technical content of the AGMA 218.01 PDF document, its noise rating classes (A, B, C, D), measurement methodology, and its replacement by AGMA 218.02 and ISO 8579-1. Practical use cases and limitations are discussed, along with guidance for interpreting legacy gear drawings that reference AGMA 218.01.
A: No. Cylindrical gears (spur and helical) only. For bevel gears, refer to AGMA ISO 17485. agma 21801 pdf
The standard mandates inspection of four primary elements:
AGMA 218.01 (now largely superseded by AGMA 910 series and ISO 6336) focuses on:
It was one of the first standards to move beyond static beam-strength formulas (like Lewis) and address real-world dynamics of rotating gears. The "butting principle" refers to a method of
AGMA 21801 is an American Gear Manufacturers Association (AGMA) standard titled: "System for Gear Tooth Measurement and Inspection Based on the Gear Tooth Butting Principle."
However, to fully understand AGMA 21801, you need to know its predecessor. Before 2018, this standard was famously known as AGMA 2015-1-A01 (or simply AGMA 2015). In a major reorganization of gear standards, AGMA renumbered many of its documents to align with ISO and global numbering conventions. AGMA 2015-1-A01 became AGMA 21801.
Unlike older gear standards, AGMA 21801 includes strict guidelines for measuring conditions, including: AGMA 218
Searching for "agma 21801 pdf" is the first step toward gear quality assurance. To summarize:
By mastering this standard, you ensure that your gears do not just rotate—they perform with predictable noise, vibration, and fatigue life. That is the value hidden inside every legitimate AGMA 21801 PDF.