UNIVERSITY OF NAIROBI DEPARTMENT OF MECHANICAL AND MANUFACTURING
UNIVERSITY OF NAIROBI DEPARTMENT OF MECHANICAL AND MANUFACTURING ENGINEERING DESIGN II FME 461 PART 15 GO NYANGASI January 2007 1
CLAVARINO’S EQUATION MAXIMUM NORMAL STRAIN THEORY APLLIED TO CLOSE ENDED THICK WALLED CYLINDER OF DUCTILE MATERIAL 2
EXTERNAL LOAD AND DIMENSIONS OF MEMBER • Sketch shows of a thick walled cylinder intended as a hydraulic cylinder. 3
LOCATION OF EXTREME STRESSES AT INNER SURFACE • For close ended cylinder, extreme stresses occurring at inner surface are 4
STRESS AT INNER SURFACE 5
STRESS ACROSS WALL • Stress distribution across the wall 6
PRINCIPAL STRESSES AT THE EXPECTED POINT OF FAILURE • This is at inners surface with stresses 7
MAXIMUM NORMAL STRAIN THREE DIMENSIONAL STRESS • This is given by the expression 8
CLOSE ENDED CYLINDER • LONGITUDINAL STRESS IS NOT ZERO • Maximum normal stresses at the inside surface of cylinder are given by 9
CLOSE ENDED CYLINDER • Substituting the values of principal stresses to obtain maximum normal strain 10
CLOSE ENDED CYLINDER • MAXIMUM NORMAL STRAIN IN THE TENSION TEST SPECIMEN 11
MAXIMUM NORMAL STRAIN • Comparing Maximum Normal Strains 12
DESIGN EQUATION • Applying a factor of safety 13
DESIGN EQUATION • Simplifying 14
DESIGN EQUATION • Simplifying 15
DESIGN EQUATION • Simplifying 16
- Slides: 16