SPX Profiles

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The Marley Geareducer®

For over 75 years, SPX Cooling Technologies has been manufacturing the most reliable geared speed reducers — designed specifically for cooling tower and ACC service.

The SPX Marley Geareducer is manufactured and designed specifically for cooling towers in HVAC, industrial and power plant applications. In shape and function, their design goes beyond normal AGMA requirements — both to maximize air movement through the cooling 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. SPX Cooling Technologies’ Geareducers are designed uniquely for cooling tower and air-cooled condenser service.

The reliability of the Geareducer comes from more than 100,000 units of experience, and from SPX’s attention to exacting quality standards of design and manufacturing. Today, every Geareducer is tested under load at our factory. Then, it’s inspected and adjusted before shipment. This has resulted in an unequalled history of trouble-free operation.


Key Features

• Outstanding durability
• Designed specifi cally 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 shaft bearings
• Long-life lip-type oil seal at input shaft
• Output shaft sealed with a maintenance-free labyrinth ring
• Timken® tapered roller bearings

Points of Difference

• Geared speed reducer designed specifi cally for cooling tower and ACC applications
• Largest installed base/proven track record - SPX Cooling Technologies has been making the Marley Geareducer line since the 1940s
• Most durable as a result of design, lubrication system, load capability
• Runs cool - does not require an auxiliary fan to cool the oil and box
• Best warranty - only SPX covers the entire Geareducer including bearings and seals
• Shortest lead time on aftermarket
• Quietest gear box

Parts Finder

Find Marley Parts and Support
1-800-4-MARLEY | 913-707-4631 (After Hours Emergency)