Tool systems for grinding and honing today’s most challenging gears
February 13, 2023
The trend towards hard fine finishing of gears for automotive transmissions is accelerating. In recent years, the focus has been on increasing the efficiency of gears in order to make optimum use of the narrow gear ratio range, gear by gear, and to reduce fuel consumption. Surface finish, in particular, is under increased scrutiny since it plays such a decisive role in achieving the noise and efficiency requirements of gear units for today’s EV applications.
In acquiring the Turkish Egeli Egesan Group the Tyrolit Group continues to implement its business expansion strategy and has further strengthened its position on the international abrasives market.
This proposed standard would not make any recommendations
regarding the required quality for any application. The
intent is to establish standard pre-finish quality classes for typical
finishing operations, which only include the inspection elements
that are important to properly evaluate pre-finish gear
quality as it applies to the finishing operation. It would be the
responsibility of the manufacturing/process engineer, quality
engineer, or other responsible individual to establish the
required pre-finish quality class for their application.
Cracks initiated at the surface of case-hardened gears may lead to typical life-limiting fatigue failure
modes such as pitting and tooth root breakage. Furthermore, the contact load on the flank surface
induces stresses in greater material depth that may lead to crack initiation below the surface if the
local material strength is exceeded. Over time the sub-surface crack propagation may lead to gear
failure referred to as “tooth flank fracture” (also referred to as “tooth flank breakage”). This paper explains the mechanism of this subsurface fatigue failure mode and its decisive influence factors, and presents an overview of a newly developed calculation model.
Here is some history that bears repeating - or at least re-reading. So take a few minutes to give it up for a long-gone Brit named Henry Maudslay
(August 22, 1771 - February 14, 1831) - also known as "A Founding Father of Machine Tool Technology." You might
also consider him an early leader in inspection, as he also invented the first bench micrometer capable of measuring to one ten-thousandth of an inch.
At the dawn of the Industrial
Revolution, so-called mechanics
were tasked with devising the precise methods that would make mass production possible. The result was the first generation of machine tools, which in turn required improved tooling and production methods.