Chapter 13, Problem 12P

A 38.1 mm pulley is fastened to a 120 mm shaft by means of square key with 150 mm long. What force tangent to pulley rim will crush and key if bearing stress is 410 Mpa? Assume key and shaft are of the same material.

Condition #1: A structural support for a machine is subjected to a static compression load of 20 kN. The support is manufactured from a circular rod made from SAE 1040 Hot Rolled steel. Specify suitable diameter for the cross section of the rod based on the basic size. Steel data are available in Table A-10 from the textbook. Condition #2: The same structural support of the basic size determined in Condition 1 is subjected to a tensile load of 15 kN that is repeated several thousand times over the life of the machine. This load is not an addition to the 20 kN. Specify a suitable steel that is suitable to this application based on the basic size determined in Condition #1. Loading of Condition #1 does not apply here. Condition #3: The same structural support from Condition 2 is heated from room temperature of 25°C. The support is placed inside a frame on both ends. There is a total clearance of 0.2 mm between the support and its frame. Initial length of the rod is 200 mm. Specify the…

3. An M16 x 2 bolt with a slotted hex nut is used to clamp together two 25 mm steel plates. The joint is assembled with a size 16 N washer underneath the bolt head. The bolt is a 5.8 class metric grade, with a proof strength of 380 MPa. The joint is intended to be permanent. Determine a suitable length for the bolt, rounded up to the nearest standard size in millimeters. Calculate the bolt stiffness, the elongation of the bolt after the necessary preload is developed, and the bolt torque required to apply the preload. Assume that coefficients of friction between the bolt, nut, and collar are all ~0.15. For steel, use E = 207 GPa. Standard threaded fastener lengths, dimensions of hexagonal nuts, and dimensions of metric plain washers are provided in the textbook appendices.