A cable and pulley system in figure supports a cage of mass 300 kg at B. Assume that this includes the mass of the cables as well. The thickness of each the three steel pulleys is t = 40 mm. The pin diameters are dp = 25 mm, dps = 30 mm and dpc = 22 mm. Allowable shear stress in the pins is 50 MPa Allowable bearing stress between the pin and the pulley is 110 MPa. Li Cable dpA = 25 mm Pulley- Pin Cable dpc = 22 mm dpB IB dpB = 30 mm Support bracket Cage at B Section a-a: pulley support detail at A and C Section a-a: pulley support detail at B 1. Calculate the maximum weight W that can be added to the cage based on shearing strength of pins. 2. Calculate the maximum weight W that can be added to the cage based on bearing strength. ANSWER: 66.5 kN (shear at A governs); 129.1 kN (bearing at B controls) Cage W

A cable and pulley system in figure supports a cage of mass 300 kg at B. Assume that this includes the mass of the cables as well. The thickness of each the three steel pulleys is t = 40 mm. The pin diameters are dp = 25 mm, dps = 30 mm and dpc = 22 mm. Allowable shear stress in the pins is 50 MPa Allowable bearing stress between the pin and the pulley is 110 MPa. Li Cable dpA = 25 mm Pulley- Pin Cable dpc = 22 mm dpB IB dpB = 30 mm Support bracket Cage at B Section a-a: pulley support detail at A and C Section a-a: pulley support detail at B 1. Calculate the maximum weight W that can be added to the cage based on shearing strength of pins. 2. Calculate the maximum weight W that can be added to the cage based on bearing strength. ANSWER: 66.5 kN (shear at A governs); 129.1 kN (bearing at B controls) Cage W

Mechanics of Materials (MindTap Course List)

9th Edition

ISBN:9781337093347

Author:Barry J. Goodno, James M. Gere

Publisher:Barry J. Goodno, James M. Gere

Chapter11: Columns

Section: Chapter Questions

Problem 11.2.4P: Repeat Problem 11.2-3 assuming that R= 10 kN · m/rad and L = 2 m.

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