Calculating Power Transmission with Belt and Rope Drives: A Comprehensive Guide

AI Thread Summary
The discussion focuses on calculating power transmission in belt and rope drives, addressing two specific problems. The first problem involves determining the power transmitted by a belt drive with an increased angle of lap from 150° to 210°, with a known belt speed and maximum tension, resulting in a maximum power of 12.56 kW. The second problem pertains to a rope drive between two shafts, where the parameters provided lead to a maximum power transmission of 446 kW and a smaller pulley speed of 390 rev/min. Participants are encouraged to identify relevant equations to solve these problems effectively. The conversation highlights the complexities involved in power transmission calculations and the importance of understanding the underlying physics.
Brabs23
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Two questions I am a bit stuck on, any kind of help would be appreciated :)

1 - In a belt drive the angle of lap on the small pulley is 150°. With a belt speed of 20m/s and a max tension of 1400N, the greatest power that can be transmitted is 10kW. What power could be transmitted for the same belt speed and max tension if an idler pully is used to increase the angle of lap to 210°. (It may be assumed that centrifugal effects are significant and the mass of the belt is 0.75kg/m)

I know the answer is 12.56kW, but even working backwards is confusing me!


2 - Power is transmitted by a rope drive between two shafts 4.5m apart. The pulleys are 3m and 2m diameter snd the total groove angle is 40°. If the rope has a mass of 4 kg/m, and the max tension is 20kN, determine the max power which the rope can transmit, and the corresponding speed of the smaller pulley. Coefficient of friction is 0.2.

Again .. the answers are 446kW and 390 rev/min
 
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