The A frame shown in the figure is attached to an overhead beam by 2 cap screws, each of which can be assumed carries half of the total load, F. The load, F, acts vertically downward varying from 0 to 2400 lb. The screws will be Grade 5. Despite recommended suggestions, the screws will be tightened to an initial stress of σi = 0.5 SP. Assuming that the stiffness of the part is twice the stiffness of the screw, i.e. KM = 2 KB: a. Recommend the appropriate screw for a reasonable factor of safety, i.e. 2 ≤ n ≤ 4.

The A frame shown in the figure is attached to an overhead beam by 2 cap screws, each of which can be assumed carries half of the total load, F. The load, F, acts vertically downward varying from 0 to 2400 lb. The screws will be Grade 5. Despite recommended suggestions, the screws will be tightened to an initial stress of σi = 0.5 SP. Assuming that the stiffness of the part is twice the stiffness of the screw, i.e. KM = 2 KB: a. Recommend the appropriate screw for a reasonable factor of safety, i.e. 2 ≤ n ≤ 4.

Mechanics of Materials (MindTap Course List)

9th Edition

ISBN:9781337093347

Author:Barry J. Goodno, James M. Gere

Publisher:Barry J. Goodno, James M. Gere

Chapter2: Axially Loaded Members

Section: Chapter Questions

Problem 2.2.9P: A safety valve on the top of a tank containing steam under pressure p has a discharge hole of...

See similar textbooks

Similar questions

A flat bar of width b and thickness t has a hole of diameter d drilled through it (see figure). The hole may have any diameter that will fit within the bar. What is the maximum permissible tensile load Pmaxif the allowable tensile stress in the material is st?
What is the maximum possible value of the clamping Force C in the jaws of the pliers shown in the figure if the ultimate shear stress in the 5-mm diameter pin is 340 MPa? What is the maximum permissible value of the applied load P to maintain a factor of safety of 3.0 with respect to failure of the pin?
A lifeboat hangs from two ship's davits. as shown in the figure. A pin of diameter d = 0.80 in. passes through each davit and supports two pulleys. are on each side of the davit. Cables attached to the lifeboat pass over the pulleys and wind around winches that raise and lower the lifeboat. The lower parts of the cables are vertical and the upper parts make an angle a =15° with the horizontal. The allowable tensile force in each cable is 1800 lb, and the allowable shear stress in the pins is 4000 psi. If the lifeboat weighs 1500 lb, what is the maximum weight that can be carried in the lifeboat?
-19 The mechanical assembly shown in the figure consists of an aluminum tube, a rigid end plate, and two steel cables. The slack is removed from the cables by rotating the turnbuckles until the assembly is snug but with no initial stresses. Afterward, the turnbuckles are tightened by 1.5 turns. Calculate the forces in the tube and the cables and determine the shortening of the tube. As= 0.85 in2 for each cable, AA= 4.5 in2, L = 20 in., Es= 29,000 ksi, EA= 10,600 ksi, and p = 1/16 in
A plane truss has joint loads P, 2P, and 3P at joints D. C, and B. respectively (see figure) where load variable P — 5200 lb. All members have two end plates (see figure For Prob. 1.8-2) that are pin-connected to gusset plates. Each end plate has a thickness/ — 0.6.2.5 in., and all gusset plates have a thickness tg= 1.125 in. IT the allowable shear stress in each pin is 12,000 psi and the allowable bearing stress in each pin is 18.000 psi, what is the minimum required diameter dminof the pins used at either end of member BE1
Continuous cable A DB runs over a small friction less pulley al D to support beam OABC, which is part of an entrance canopy for a building (see figure}. The canopy segment has a weight W = 1700 lb that acts as a concentrated load in the middle of segment AB. (a) What is the maximum permissible value of load P at C if the allowable force in the cable is 4200 lb? (b) If P = 2300 lb, what is the required diameter of pins A, B, and D? Assume that the pins are in double shear and the allowable shear stress in the pins is 10 ksi.
A pressurized circular cylinder has a sealed cover plate fastened with steel bolts (see figure). The pressure P of the gas in the cylinder is290psi, the inside diameter D of the cylinder is 10.0 in., and the diameter dBof the bolts is 0.50 in. I f the allowable tensile stress in the bolts is 10,000 psi, find the number n of bolts needed to fasten the cover.
A steel punch consists of two shafts: upper shaft and lower shaft. Assume that the upper shaft has a diameter d1= 24 mm and the bottom shaft has a diameter d2= 16 mm. The punch is used to insert a hole in a 4 mm plate, as shown in the figure. If a force P - 70 kN is required to create the hole, what is the average shear stress in the plate and the average compressive stress in the upper and lower shaft of the punch?
A safety valve on the top of a tank containing steam under pressure p has a discharge hole of diameter d(see figure). The valve is designed to release the steam when the pressure reaches the value Pmax If the natural length of the spring, is L and its stiffness is k, what should be the dimension ft of the valve? (Express your result as a formula for h.)
Solve the preceding problem if F =90 mm, F = 42 kN, and t = 40°MPa
An idealized column is composed of rigid bars ABC and CD joined by an elastic connection with rotational stiffness ßRIat C. There is a roller support at B and an elastic support at D with translationa1 spring stiffness ß and rotational stiffness ßR2. Find the critical buckling loads for each of the two buckling modes of the column. Assume that L = 3 m, ß = 9 kN/m, and ßR]= ßR1= ßL2. Sketch the buckled mode shapes.
Three round, copper alloy bars having the same length L but different shapes are shown, in the figure. The first bar has a diameter d over its entire length, the second has a diameter d over one-fifth of its length, and the third has a diameter d over one-fifteenth of its length. Elsewhere, the second and third bars have a diameter Id. All three bars are subjected to the same axial load P. Use the following numerical data: P = 1400 kN, L = 5m,d= 80 mm, E= 110 GPa. and v = 0.33. (a) Find the change in length of each bar. (b) Find the change in volume of each bar.