RIVETED JOINTS 19 



t = | inch, d = 1.3 V7= .796 ; selecting d to the nearest sixteenth 

 of an inch, we have d = l| inch, n = 5, and m = 9. 



P t = (P~ d)ts t = (p- if )f 55,000, 



P g = m Ss = 9 (.518) 38,000 = 177,666.7, 



p c = n tds e = 5 | if 80,000 = 121,875. 

 ... (^_i|)|. 55,000 = 121,875. 

 Solving p = 6.71, we will then take 



p = 6| inches ; 



.. 



p 108 



The joint then has an efficiency of 88 per cent, and the inner rows 

 of rivets will have a spacing of 3| inches. 



The present discussion of riveted joints is not given with the in- 

 tention of completing the subject in regard to all forms and methods 

 of construction, but for use in computations and design of such joints 

 as are often found in boiler construction. 



118. Determine the efficiency of a single-riveted lap joint if t = T 3 g 

 inch, d = | inch, and p=\\ inches. 



119. Find the efficiency of a single-riveted lap joint if t | inch, 

 d = 1 J inch, and p = 2^. inches. 



120. Calculate the efficiency of a single-riveted lap joint if t = J 

 inch, d = l^ 3 g inches, and p = 2-j 7 g inches. 



121. Determine the efficiency of a single-riveted lap joint if t = J- 

 inch, d = 1 -Jg- inches, and p == 2y 5 g inches. 



122. Calculate the efficiency of a single-riveted lap joint if t = T 5 6 

 inch, d = l| inch, and p = 2 -Jg- inches. 



123. A single-riveted lap joint, with t = T 7 g inch, d = 1 inch, and 

 p = 2J inches, sustains a tension of 5000 pounds on each repeating 

 section. Compute the efficiency of the joint and the factors of safety. 



124. Determine the pitch of a single-riveted lap joint where t = J- 

 inch, and d = \ inch, so that the strength of the joint against tearing 

 the plate between the rivet holes shall equal the shearing strength of 

 the rivets. Calculate also the efficiency of the joint. 



/ 125. Determine the efficiency of a double-riveted lap joint where 

 t = | inch, d l| inch, and p = 3^ inches. 



