Design the longitudinal and circumferential joint for a boiler whose diameter is $2\mathrm{.}4$ metres and is subjected to a pressure of $1\frac{N}{m}{m}^2.$ The longitudinal joint is a triple riveted butt joint with an efficiency of about $85\%$ and the circumferential joint is a double riveted lap joint with an efficiency of about $70\%.$ The pitch in the outer rows of the rivets is to be double than in the inner rows and the width of the cover plates is unequal. The allowable stresses are :

${}_t=77$MPa;$=56$MPa and ${}_c=120$MPa Assume that the resistance of rivets in double shear is $1\mathrm{.}875$ times that of single shear. Draw the complete joint.