Geareducer® - Double Reduction
OVERVIEW Marley industrial Geareducers are manufactured and designed specifically for cooling towers in large industrial and power plant applications. In shape and function, their design goes beyond normal AGMA requirements—both to maximize air movement through the tower, and to minimize the impact of maintenance.


Although the primary function of a Geareducer is to reduce the speed of the driver (usually an electric motor) to a speed which is conducive to good fan performance, it must satisfy other criteria as well. For example, it must provide primary support for the fan — withstand the shock loads imposed at start-up and during subsequent speed changes—anchor the fan against lateral movement in response to rotational forces—and contribute as little as possible to power transmission losses as well as the generation of noise.

Given these requirements, many manufacturers of mechanical equipment provide acceptable speed reducers. Designed for more forgiving commercial applications, these units are often unprepared for the rigors and peculiarities of cooling tower service, such as the corrosive effects of operation (often intermittent) within an exceedingly humid environment. As a result, both the life expectancy of these commercial speed reducers— and the thermal performance of the cooling towers on which they are installed often suffer.

Marley is the only major manufacturer whose Geareducers are designed uniquely for cooling tower service. And, since we warrant not only the Geareducer, but the thermal performance of the cooling towers on which they operate as well, development, design, and manufacture are taken very seriously. This has resulted in an unequalled history of trouble-free operation.


Genuine Marley OEM parts are precision-engineered to provide you with a reliable product. While other suppliers may offer parts at an initial savings, you risk lowering performance — and losing FM and CTI ratings. Marley OEM parts provide the durability you can trust because we design and manufacture them exclusively for cooling towers.

With plant operation relying on your cooling tower performance, it’s important to select the parts that are among the highest quality available — Marley OEM parts.

Featured Video:

Marley Pinion Shaft Oil Seal Replacement
  • Outstanding durability

  • Designed specifically for cooling tower duty

  • Designed to meet or exceed the requirements of CTI Std. 111 and AGMA standards

  • Minimum L10A service life of 100,000 hours on both input and output shafts

  • Long-life lip-type oil seal at input shaft

  • Output shaft sealed with a maintenance-free labyrinth ring

  • Timken tapered roller bearings

  • Two-stage (spiral bevel/helical) gear reduction for efficient power transmission


Marley Cooling Tower Parts