A right angled bell crank lever is to be designed to raise a load of 5 kN at the short arm end. The lengths of short and long arms are 100 and 450 mm respectively. The lever and the pins are made of steel 30C8 (S = 400 N/mm2). And the factor of safety is 5.the permissible bearing pressure on the pin is 10 N/mm². The lever has a rectangular cross section and the ratio of width to thickness is 3:1. The length to diameter ratio of the fulcrum pin is 1.25:1. Calculate (i) The diameter and length of the fulcrum pin (ii) The dimensions of the cross section.

A right angled bell crank lever is to be designed to raise a load of 5 kN at the short arm end. The lengths of short and long arms are 100 and 450 mm respectively. The lever and the pins are made of steel 30C8 (S = 400 N/mm2). And the factor of safety is 5.the permissible bearing pressure on the pin is 10 N/mm². The lever has a rectangular cross section and the ratio of width to thickness is 3:1. The length to diameter ratio of the fulcrum pin is 1.25:1. Calculate (i) The diameter and length of the fulcrum pin (ii) The dimensions of the cross section.

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 11.4.12P: A fixed-pinned column is a W310 × 21 steel shape and is designed to carry an axial load of 125 kN....

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