172 



HANDBOOK OF MECHANICAL DESIGN 



BELT HORSEPOWER CHARTS 



Determining Belt Tension Resulting from Centrifugal Force 



30 40 50 60 80 lOp 



wv 



~Q~ fn Lb. per In. Wid+h 



The fiat-belt horsepower chart on the preceding page enables the designer to 

 obtain the linear velocity of the belt in a given drive. In the illustrative example 

 given with that chart, the linear velocity of the belt was shown to be 3,160 ft. per min. 

 By assuming a belt whose unit weight is 0.15 lb. per ft. per in. width, the additional 

 belt tension set up by centrifugal force can be obtained from the chart on this page. 



From the point in the vertical scale designating 0.15 in. per ft. per in. width, trace 

 horizontally to the right to the point representing a velocity of 3,160 ft. per min., as 

 indicated by the diagonals. Then drop down vertically to the horizontal scale, 

 which gives the value of WV^/G as 13 lb. per in. width of belt. 



