Design Equations for Sheaves using Wire Rope

[kklinger]

Does anybody know the equations for calculating stresses in a sheave? I know the P=2*T/D*d equation for sizing a sheave diameter for the wire rope. I have what I believe is a single piece steel rim pulley and for use at low speeds.

TIA

kklinger

 

[CanuckMiner]

Shigley's "Mechanical Engineering Design" givees the same equation that you gave, for calculating the bearing pressure of the rope acting on the sheave groove. It also gives a table (sourced from AISI Wire Rope Users Manual, 1979) that illustrates the maximum allowable bearing pressures of ropes on sheaves of various materials. For Cast Steel (HB = 160 min.):

6 x 7 rope, reg. lay, 550 psi
6 x 19 reg lay, 900 psi
6 x 37 reg lay, 1075 psi
8 x 19 reg lay, 1260 psi

6 x 7 lang lay, 600 psi
6 x 19 lang lay, 1000 psi
6 x 37 lang lay, 1180 psi

Wire rope manufacturers could probably offer you more insight, if required.

Cheers,
CanuckMiner