Methods of examining large ring gear
teeth to detect surface breaking discontinuities have often been time-consuming and limited in terms of data collected. Methods such as visual and magnetic particle inspection can miss critical discontinuities. However, a new ASTM international standard provides a more effective method for gear examination using eddy current array, a technology that has been widely used but, until now, not standardized.
The new chairman of the AGMA Technical Division Executive Committee explains what's involved in the process of developing technical standards at the AGMA.
AGMA introduced ANSI/AGMA 2015–2–A06—
Accuracy Classification System: Radial System for Cylindrical Gears, in 2006 as the first major rewrite of the
double-flank accuracy standard in over 18 years. This document explains concerns related to the use of
ANSI/AGMA 2015–2–A06 as an accuracy classification system and recommends a revised system that can be of more service to the gearing industry.
The first edition of the international calculation method for micropitting—ISO TR 15144–1:2010—was just published
last December. It is the first and only official, international calculation method established for dealing with
micropitting. Years ago, AGMA published a method for the calculation of oil film thickness containing some comments
about micropitting, and the German FVA published a calculation method based on intensive research results. The FVA and the AGMA methods are close to the ISO TR, but the calculation of micropitting safety factors is new.
Faithful Gear Technology readers may recall that our July 2009 issue contained an update of the deliberations
provided by Bill Bradley. Now, almost two years later, there is an ISO/IEC wind turbine gearbox standard out for draft international standard ballot (ballot closes 2011-05-17).
An offshore jack-up drilling rig is a barge upon which a drilling platform is placed. The barge has legs that can be lowered to the sea floor to support the rig. Then the barge can be “jacked up” out of the water, providing a stable work platform from which to drill for oil and gas. Jack-up drilling rigs were first introduced in the late 1950s. Rack-and- pinion-type jack-up units were introduced soon after that and have dominated the industry ever since.