For the lubrication of open gear drives
used in different industrial applications
such as cement and coal mills,
rotary furnaces, or where the sealing
conditions are difficult, semi-fluid
greases are often used in preference to
fluid oils. For girth gear applications
the greases are used with a splash or
spray lubrication system. The selection
of such greases influences pitting lifetime
and the load-carrying capacity of
the gears, as well as wear behavior
This paper provides a mathematical framework and its implementation for calculating the tooth geometry of
arbitrary gear types, based on the basic law of gear kinematics. The rack or gear geometry can be generated
in two different ways: by calculating the conjugate geometry and the line of contact of a gear to the given
geometric shape of a known geometry (e.g., a cutting hob), or by prescribing the surface of action of two gears in contact and calculating the correspondent flank shapes.
Varying installation requirements for worm gears, as, for example, when used in modular gear systems, can necessitate grease lubrication - especially when adequate sealing for oil lubrication would be too complex. Such worm gears are being increasingly used in outside applications such as solar power plants and slew drives. While knowledge about the operating conditions is often appropriate, the basic understanding for load capacity and efficiency under grease lubrication is quite poor. Investigations done at FZG and sponsored by FVA/AiF are shown here to give an impression of the basic factors of load capacity and efficiency. The results of the investigation indicate a satisfying quality of calculations on heat, load capacity and efficiency based on characteristic parameters of the base oil with only slight modifications to the methodology known from DIN 3996 or ISO TR 14521.
This article is designed to help describe the selection process of a reducer to be used in the parcel handling industry. It will go over the different applications for which gearboxes are used throughout parcel handling facilities such as UPS, FedEx and DHL.
