Nt1210 Lab 3.1.3
Two chains are required to transmit power from the engine to the tire. A #35 duplex chain transmits power from the crankshaft of the engine to the main shaft. A #35 single strand chain transmits power from the output sprocket to the tire. To calculate the length of the chain necessary to last for 10^7 cycles of the main shaft, equations (5) is used: H_2=1000/K_s [K_r (N_1/n_1 )^1.5 p^0.8 (L_p/100)^0.4 (15000/h)^0.4 ] (5)
Where H_2 is the horsepower transmitted between shafts, Ks is the strand correction factor, Kr is the roller correction factor, N_1 is the number of teeth of the driving sprocket, n_1 is the rpm of the driving sprocket, p is the pitch of the chain, Lp is the length of the chain in pitches, and h is the life in hours of the …show more content…
A 3.0” diameter and 0.375” pitch are necessary for a 25 tooth sprocket, and a 6.45” diameter and 0.375” pitch are necessary for a 54 tooth sprocket. This creates a 46.3% reduction in rotational speed. With a center-to-center distance of 5” between the sprockets and a 0.3” clearance between the two sprockets, length can be calculated from equation (6): L=√(4C^2-(D-d)^2 )+1/2(Dθ_D+dθ_d) (6)
Where L is the length of a given chain in inches, C is the center distance, D is the diameter of the larger sprocket, d is the diameter of the smaller sprocket, and θ_d and θ_D are contact angles of the sprockets. A chain length of 42 pitches is necessary with a designed 5 in. center-to-center distance.
The calculations for the duplex #35 chain can be repeated for the single #35 chain. A 10.7” diameter and 0.375” pitch is necessary for a 90 tooth sprocket connected to the tire. A 2.29” diameter and 0.375” pitch is necessary for a 19 tooth sprocket connect to the output of the main shaft. This provides a 21.1% reduction between the two sprockets. The center-to-center distance is determined by the wheel base, resulting in C being 25”. Following equation (6), the chain length is 118
Where H_2 is the horsepower transmitted between shafts, Ks is the strand correction factor, Kr is the roller correction factor, N_1 is the number of teeth of the driving sprocket, n_1 is the rpm of the driving sprocket, p is the pitch of the chain, Lp is the length of the chain in pitches, and h is the life in hours of the …show more content…
A 3.0” diameter and 0.375” pitch are necessary for a 25 tooth sprocket, and a 6.45” diameter and 0.375” pitch are necessary for a 54 tooth sprocket. This creates a 46.3% reduction in rotational speed. With a center-to-center distance of 5” between the sprockets and a 0.3” clearance between the two sprockets, length can be calculated from equation (6): L=√(4C^2-(D-d)^2 )+1/2(Dθ_D+dθ_d) (6)
Where L is the length of a given chain in inches, C is the center distance, D is the diameter of the larger sprocket, d is the diameter of the smaller sprocket, and θ_d and θ_D are contact angles of the sprockets. A chain length of 42 pitches is necessary with a designed 5 in. center-to-center distance.
The calculations for the duplex #35 chain can be repeated for the single #35 chain. A 10.7” diameter and 0.375” pitch is necessary for a 90 tooth sprocket connected to the tire. A 2.29” diameter and 0.375” pitch is necessary for a 19 tooth sprocket connect to the output of the main shaft. This provides a 21.1% reduction between the two sprockets. The center-to-center distance is determined by the wheel base, resulting in C being 25”. Following equation (6), the chain length is 118