A steel pipe of 300-mm outer diameter is fabricated from an 8-mm-thick plate by welding along a helix that forms an angle of 20° with a plane perpendicular to the axis of the pipe Knowing that a 250-kN axial force P and a(n) 12-KN-m torque T, each directed as shown, are applied to the pipe, determine the normal and in-plane shearing stresses in direction respectively, normal and tangential to the weld, using Mohr's circle. T 8 mm Weld 20° The normal stress oy is- 34.066 MPa, and the in-plane shearing stress Txy is 11.538 MPa.

3 A bar of diameter 25mm has an axial hole 19mm bored out concentric with the outer circumference. The bar is submitted to the following loads simultaneously: (a) An axial tension of 13 kN, (b) A bending moment of 100Nm. Determine the maximum and minimum direct stresses on the section of the bar.

Prob. # 5] A steel rod of 25 mm diameter is fitted inside a brass tube of 25 mm internal diameter and 375 mm external diameter. The projecting ends of the steel rod are provided with nuts and washers. The nuts are tightened up so as to produce a pull of 5 kN in the rod. The compound is then placed in a lathe and the brass is turned down to 4 mm thickness. Calculate the stresses in the two materials.

A 20 mm diameter steel rod passes concentrically through a bronze tube (200+SN) mm long, 50 mm external diameter and 40 mm internal diameter. The ends of the steel rod are threaded and provided with nuts and washers which are adjusted initially so that there is no end play at 25°C.. 1. Assuming that there is no change in the thickness of the washers, if the stress produced in the steel is (200+SN) MN/m2 when one of the nuts is tightened, the pitch of the thread being 1 mm. Find the number of turns for the nut and stress in bronze tube.2. If the temperature of the steel and bronze is then raised to 4O°C find the changes that will occur in the stresses in both materials. The coefficient of linear expansion per C is 10 x10-6 for steel and 17 x10-6 for bronze. E for steel = 210 GN/m2. E %3D for bronze = 100 GN/m2.. Note: SN = %3D Student number Student Number =32

A pressure vessel of 225-mm inner diameter and 6-mm wall thickness is fabricated from a 1.2 m section of spirally welded pipe AB and is equipped with two rigid end plates. The gage pressure inside the vessel is 2 MPa, and 45-kN centric axial forces P and P' are applied to the end plates. P' A 1.2 m 35⁰ B Determine the shearing stress parallel to the weld. The shearing stress parallel to the weld is P MPa.

Problem 8.12 A bar of rectangular cross-section, with a width of 60 mm and a thickness of 40 mm, is bent in the shape of a horse shoe having a mean radius of 70 mm. Two equal and opposite forces of 10 kN each are applied at a distance of 12 cm from the centre line of the middle section so that they tend to straighten the rod. Find the maximum ten- sile and compressive stresses and construct a diagram showing the vari- ation of the normal stresses over the central section.

A steel pipe of 300-mm outer diameter is fabricated from an 8-mm-thick plate by welding along a helix that forms an angle of 20° with a plane perpendicular to the axis of the pipe. Knowing that a 250-kN axial force P and a 12-kN-m torque T. each directed as shown, are applied to the pipe, determine the normal and in-plane shearing stresses in directions, respectively, normal and tangential to the weld. T The normal stress is - The shear stress is- Weld 20⁰ 8 mm MPa MPa.

State clearly the assumptions made in Lame's theory of thick cylinders. Assuming fundamental formula for radial and hoop stresses in a thick cylinder, prove that when a collar having an internal diameter D, and an external diameter D, is shrunk on to a solid shaft of the same material and having an external diameter D1 + 8(8 being small shrinkage allowance). then the radial pressure at the E8 (D; – D²) 2 D,D joint is equal to

Q6)A shaft 100mm diameter is subjected to a twisting moment of /KNm, together with a bending moment of 2kNm. Find, at the surface of the shaft, (a) the principal stresses, (b) the maximum shear stress. Confirm your answer by means of Mohr's stress circle diagram, and from the diagram determine the magnitude of the normal stress on a plane inclined at 25° counter clock wise to the plane on which oxstress acts.

3. A circular steel cylinder of external diameter 0.2 m and internal diameter 0.1 m is shrunk onto a circular aluminium alloy cylinder of external diameter 0.1 m and internal diameter 0.05 m, where the dimensions are nominal. Determine the radial and hoop stresses at the bores and outside surfaces, such that when there is an internal pressure (retained by end caps) of 300 MPa, the maximum hoop stress in the inner cylinder is 150 MPa.