Related Resources: calculators

### Horsepower Rating Synchronous Timing Belt Equations and Calculator

Belt Drive Design and Engineering
Mechanical Gear Design and Engineering

Synchronous Timing Belt Horsepower Rating Equation and Calculator per. ANSI RMA IP-24, ISO 5299 and IS 9804.

The horsepower rating formulas for synchronous belts, other than the MLX section, are determined from the following formulas, where the number in parentheses is the belt width in inches.

Use torque rating design formulas for synchronous belts MLX sections:
Torque Rating Synchronous MLX Timing Belt Equation and Calculator

Synchronous Timing Belt Horsepower Rating Calculator Preview

Horsepower rating formulas

XL (0.38) width
HP = Kz [ d ( r / 1000 ) ( 0.0916 - 7.07 x 10-5 (d r)2 ) ]

L (1.00) width
HP = Kz [ d ( r / 1000 ) ( 0.436 - 3.01 x 10-4 (d r)2 ) ]

H (3.00) width
HP = Kz [ d ( r / 1000 ) ( 3.73 - 1.41 x 10-3 (d r)2 ) ]

XH (4.00) width
HP = Kz [ d ( r / 1000 ) ( 7.21 - 4.68 x 10-3 (d r)2 ) ]

XXH (5.00) width
HP = Kz [ d ( r / 1000 ) ( 11.4 - 7.81 x 10-3 (d r)2 ) ]

Where:

HP = the maximum horsepower rating recommended for the specified standard belt width having six or more teeth in mesh and a pulley surface speed of 6500 fpm or less.
d = pitch diameter of smaller pulley in belt mechanism, inch.
r = rpm of fastest shaft
Kz = HP rating multiplier (see Table Below). Torque ratings for drives with less than six teeth in mesh must be corrected as shown.

Horsepower ratings for drives with less than six teeth in mesh must be corrected as shown in Table given below

 Teeth in Mesh (N) Factor Kz 6 or more 1.00 5 0.80 4 0.60 3 0.40 2 0.20

FPM to RPM Equation:

r = s / ( π d )

RPM to FPM Equation:

s = r π d

Where:

r = rpm
s = ft / min
d = diameter of pulley in ft

Note:

• Total horsepower ratings are the same for double-sided as for single-sided belts.
• Manufacturers specify percentage of horsepower available for each side of the belt.

Related:

References:

ANSI / RMA IP-24, ISO 5299 and IS 9804.