Design the longitudinal and circumferential joint for a boiler whose diameter is $2\mathrm{.}4$ m and is

subjected to a pressure of $1$

$2$ N mm

$.$ 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

widths of the cover plates are unequal. The allowable stresses are:

$$ t

$77$

MPa,

$$

$56$ MPa and

$$ c

$$

$120$ MPa. Draw the complete joint.