In order to select the optimal belt type and to calculate the required belt dimensions it is crucial to have exact information on the application, the drive data and the operating conditions.
For the calculation of a common two-pulley power transmission belt the following data are required :
PM = motor power or power to be transmitted [kW]
n1 = number of revolutions of driving pulley[1/min]
n2 = number of revolutions of driven pulley[1/min]
d1 = diameter of driving pulley [mm]
d2 = diameter of driven pulley [mm]
c = center distance [mm]
| 1. Fan drive to be converted to Flat drive | 15 KW |
| 2. Actual service factor of usage | 0.80 | 3. No. of Hours of Opertation per day | 16 Hours |
| 4. No. of Hours of Opertation per year | 300 Days |
| 5. Power Traffic Per Unit | Rs. 10 |
| 6. Expected Savings By Conversion | 5% |
| Annual Savings | |
| = KW x Serv Factor x % savings x Hrs/day x No of days x Tariff = 15 x 0.8 x 0.05 x 16 x 300 x 10 = Rs 28,800 per year | |
| Cost of replacement of Vee belts per annum = Rs 4,000 | |
| Total annual savings | |
| = Power savings + Vee belt replacement cost = Rs 28,800 + Rs 4,000 = Rs 32,800 per year |
|
| Cost of installation of Flat belt system including Belt and Pulleys = Rs 48,000 | |
| Pay back = Cost of replacement / operational savings = Rs 48,000 / Rs 32,800 = 1.5 years or 18 months |
|
| Anticipated savings in 4 years ( expected life of Flat belt is 4 years ) = Rs 28,800 x 4 + 4000 = Rs 119,200 |
|
