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 10.2.12.2 Width. The width of belts should conform to the following:
Minimum Width
Total Travel
(in inches)
(in feet)
12
0 - 100
14
100 - 150
16
More than 150
10.2.12.3 Strength. The strength of belts should be not less than 1,500 pounds per inch of belt
width for belts having a distance between pulley centers not in excess of 100 feet, and 1,800
pounds per inch of belt width for belts having a distance between pulley centers of over 100 feet,
but not in excess of 200 feet for over 200 feet, 2,450 pounds per inch of belt width.
10.2.13 Belt Fastenings
Belts can be fastened by a lapped splice or by a butt-splice with a strap on each side of the belt
as follows:
a. For lapped splices, the overlap of the belt at the splice must be not less than three feet
when the total travel of the manlift does not exceed 100 feet and not less than four feet if the
travel exceeds 100 feet.
b. When butt splices are used, the straps must extend at least three feet on one side of the butt
for travel, not in excess of 100 feet, and four feet for travel in excess of 100 feet.
For 12 inch belts, the joint must be fastened with not less than 20 special elevator bolts, each of a
minimum diameter of 1/4 inch. Such bolts shall be arranged symmetrically in five rows so
arranged as to cover the area of the joint effectively. Reference should be made to Figures 10-4
and 10-5. Observe the proper belt splicing procedures. The minimum number of bolts for a belt
width of 14 inches shall be not less than 23 and for belt widths of 16 inches, the number of bolts
shall be not less than 27.
10.2.14 Pulleys
Drive pulleys and idler or boot pulleys should have a diameter of not less than 20 inches.
10.2.15 Pulley Protection
The machine must be so designed and constructed as to catch and hold the driving pulley in
the event of shaft failure.
10-9
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