A thermo-mechanical model of a splash lubricated one-stage gear unit is presented. This system corresponds to a first step towards the design of a hybrid vehicle gearbox that can operate up to 40,000 rpm on its primary shaft. The numerical model is based on the thermal network method and takes into account power losses due to teeth friction, rolling-elements bearings and oil churning. Some calculations underline that oil churning causes a high amount of power loss. A simple method to reduce this source of power losses is presented, and its influence on the gear unit efficiency and its thermal capacity is computed.

The U.S. Space Shuttle fleet was originally intended to have a life of 100 flights for each vehicle, lasting over a 10-year period, with minimal scheduled maintenance or inspection. The first space shuttle flight was that of the Space Shuttle Columbia (OV-102), launched April 12, 1981. The disaster that destroyed Columbia occurred on its 28th flight, February 1, 2003, nearly 22 years after its first launch.

Reducing losses and increasing profits by instituting a motor management plan is what this series of articles is all about. Here in Part I, we discuss how to create a motor inventory and establish repair-or-replace motor guidelines. Subsequent topics in this three-part series will address (Part II) motor failure policies and purchasing specifications, and (Part III) repair specifications and preventive and predictive maintenance, respectively.

Last week in our bearing shaft and housing fit discussion, we covered the IT chart — along with the shaft and housing charts — just to understand t...

News From Around the Gear Industry

The Department of Energy estimates that 4 million megawatts of potential power—four times the amount all U.S. power plants combined currently produce—exists in offshore wind energy. Construction of America’s first offshore wind turbines began in July. The wind farm, which is being constructed off the coast of Block Island, RI, will consist of five turbines. Together, they will produce 30 MW.

Calendar of upcoming events

rotary-type blowers? Examples: for motor KW; RPM; temperature; pressure production; lifetime; etc. In other words, how do I choose between belts or couplings?

Like Moses descending from Mount Sinai toting a couple of stone tablets, Kate Achelpohl, director of member communications at PMMI and herald of all things Pack Expo, came hither proclaiming the four commandments of the forthcoming show:

I don’t know about you, but the recession of 2008-2010 sticks in my mind like a bad penny. Since that time, I am never able to simply say ...