HJD INSTITUTE OF TECHNICAL EDUCATION AND RESEARCH KERASUB-STRUCTURAL ANALYSIS 1TOPIC-THIN CYLINDERGROUP MEMBERS-KUNAL BHANUSHALI(83)SMIT PARMAR(71)

INTRODUCTIONCylinders and spherical vessels are used in the engineering field to store and transport fluids.Such vessels are tanks, boilers, compressed air receivers, pipe lines etc.These vessels when empty, are subjected to atmospheric pressure internally as well as externally and the resultant pressure on the walls of the shell is nil.Whenever a vessel is subjected to an internal pressure due to air, water, steam etc. its walls are subjected to tensile stresses.

THIN CYLINDER SHELLWhen , It is called thin cylindrical shell. t=thickness of the shell d=internal diameter of shell.In thin cylindrical shells hoop stress and longitudinal stresses are constant over the thickness and radial stresses are negligible.When ,It is called thick cylindrical shell.

STRESSES IN THIN CYLINDRICAL SHELLSWhenever a thin cylindrical shell is subjected to an internal pressure(p), its wall are subjected to two types of tensile stresses.A. Hoop stress(circumferential stress)B. Longitudinal stress.Hoop stress : Consider a thin cylindrical shell subjected to an internal

pressure as shown in fig. = circumferential stress in the shell material. p= internal diameter of shell t= Thickness of the shell Total pressure P=Pressure*Area = pdl Resulting Area= A=2tl Circumferential stress( ),

LONGITUDINAL STRESS

Total pressure along length of the shell,

Resisting Area,

Longitudinal stress ,

stress act in the direction of length

CHANGE IN DIMENSIONS OF A THIN CYLINDRICAL SHELL DUE TO INTERNAL PRESSUREConsider a thin cylindrical shell subjected to internal pressure.p= internal pressured=internal dia. Of shellt=thickness of the shelll=length of the shellWe know that, andLet, δd= change in diameter of shell δl= change in length of shell

Circumferential strain,

Longitudinal strain,

change in diameter=δd= .d change in length=δl= .l

Ex:- A thin cylindrical shell with internal dia. 125 mm and wall thickness 12 mm is subjected to a steam pressure 10 Find circumferential and longitudinal stress in the material. d=125 mm t=12 mm p=10