Industry: Food and Beverage

Application: Flour Mill Roll Stands

Products: Baldor•Reliance XE Motors with Roller Bearings on End Drive

The Challenge

Flour Mills in the United States have been in operation for over 120 years. As a 

result, much of the equipment used today to mill flour has been in operation for 

many years and is in need of upgrading. One example of this equipment is U-frame 

motors, which have been in use since the 1950’s. U-Frame motors were the standard 

design until the current T-frames were introduced in 1964. With improved insulation, 

T-Frames delivered more horsepower in smaller frames and also were designed 

with larger shafts and bearings per frame size to accommodate greater loads. As a 

result, U-frame motors are considered a legacy product with long lead times, higher 

costs and have no identifiable advantage over T-frame motors for this Flour Mill Roll 

Stand application.

The Baldor Solution

The Baldor Industry Solutions team, local Sales Engineer, and Baldor Cleveland 

District office worked with the local distributor to evaluate the application and deliver 

back to the end-customer our XE Premium Efficient T-frame motor solution. With the 

assistance of Baldor Industry Solutions Engineering we calculated that we could 

improve the motor L10 bearing life from 40,000 hours to 100,000 by utilizing a 

roller bearing on the motor drive end. Calculation as follows:

Input Parameters:

Motor Hp ......................40.00 Driven RPM ..................... 714.67 

Driver RPM.................1785.00 Center Distance ................. 72.00 

Service Factor ..................1.30 

Drive Selection:

Belt Profile........................... BX Sheave O.D. Driver .............. 6.40 

Belt Size....................... BX180 Sheave O.D. Driven ........... 16.00 

Number of belts.....................6 

Resultant Drive Data:

Belt Speed (FPM) ........2995.47

Center Distance (in) .........73.13

Service Factor.................1.94

Shaft Load (lbs):

Static Min....................884.16 Static Max. ................... 1326.23 

Dynamic Belt Pull...........883.55 

Installation Data:

Belt Deflection at Center of Span (inches) 1.14 

Deflection Force per Belt (lbs): Min: 6.04 Max: 6.96 

Total Defl. Force for 6 Banded belts: Min: 36.23 Max: 41.77
T-Frame Option- 320T

Calculated Ball Bearing L10 Life based on Dynamic Belt Pull of 883.55 is 17,500 Hours

Calculated Roller Bearing L10 Life based on Dynamic Belt Pull of 883.55 100,000+Hours

U-Frame Option- 360U

Calculated Ball Bearing L10 Life based on Dynamic Belt Pull of 883.55 is 40,000 Hours

Along with the up-front cost savings, by utilizing a Roller Bearing we have increased the 

theoretical life of the motor bearing by 60,000 hours compared to the U-frame 360 frame ball 

bearing. This savings can be calculated over the life of the improved motor design but is not 

quantified in this report.

Our Baldor XE Premium motor with a Roller Bearing on the drive end not only is a superior 

product to the 1952 U-Frame design, it also costs less. Example:

The Savings

Existing U-Frame motor cost ........................................$ 2,979

New T-Frame motor cost with Roller Bearing.............$ 1,771

Savings per motor ........................................................$ 1,208

Number of U-frame motors in operation............................74

Total Unit Price Savings ..................................$89,392

The Conclusion

By focusing on providing our customers with the most Innovative Baldor Electric Product Solutions, 

we can identify solutions that range from cutting edge Rare Earth Magnet Servo Technology to 

upgrading 1952 design U-Frame motors that no longer deliver practical customer value. 

 World Headquarters

P.O. Box 2400, Fort Smith, AR 72902-2400 U.S.A., Ph: (1) 479.646.4711, Fax (1) 479.648.5792, International Fax (1) 479.648.5895

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