RUPTURE STRESSES IN BEAMS AND CRANE HOOKS. 



221 



In addition an examination was made of the investigation # by Professor Goodman 

 into the strength of drop-forged steel hooks, which was published in Engineering, 

 and also of the results contained in his paper f on " Crane Hooks," which followed on 

 the lines of Andrews' theory and which was published in the Proceedings of the 

 Institution of Civil Engineers. 



The values of (yt + y e ) in terms of the depth of section and of the consequent 

 values of "f" in formula (3) is given below for the various sections investigated: — 





Description of Hook. 



(Vt + y,)- 



f. 



(1) 



Circular ...... 



■425d 



Ad 



(2) 



Rectangular ..... 



■5d 



,WL 

 Ad 



(3) 



,, with rounded ends . 



•i3d 



465 A^ 



(4) 



Goodman's drop-forged steel 



1-43/i 



4-65^_ L 

 Ah 



(5) 



,, wrought-iron 1st set . 



•48A 



« 7 S 



Ah 



(6) 



,, ,, 2nd set 



■i8h 



Ah 



These were found to justify the conclusions which are set forth in the present 

 paper, and an analysis of these along with the experimental results are given in 

 Table III. 



Table III. 















<N 



+ "1 



Max. Direct 





Description. 



Material. 



Depth. 



Area. 



Load. 



L" 





~ cr 1 



^ CO 



Tensile Stress. 



Elastic 





Ins. 



Sq. in. 



Tons. 





h3 I . <0 



te; <j & 



" 1 





Formula. 



(Cold). 



(Annealed). 



No. 1 round 



W.I. 



1-1 



•95 



4-25 



1-3 



25-97 



24-6 





46-64 



., 2 „ 



)> 



1-0 



•78 



3-90 



1-1 



25-70 



25-1 





48-58 



„ 3 „ 



B.B.H. 



1-02 



•83 



4-35 



1-0 



24-45 



23-05 



23-41 



46-61 



„ 4 „ 



Swed. 



1-02 



•82 



3-24 



1-15 



20-83 



20-00 



20-12 



39-38 



,. 5 „ 



S.M.S. 



1-00 



•78 



38 



1-1 



2520 



2500 



25-80 



46-97 



„ 6 „ 



Mild S. 



1-02 



•82 



30 



1-3 



21-92 



24-4 



24-17 



40-70 



,, 7 rect. 



1) 



•93 



•46 



25 



1-2 



27-90 



26-8 



... 



48-86 



,. 8 „ 



W.I. 



1-02 



•82 



3 



Avera 



1-3 



%e value 



21-7 



24-6 







24-20 



24-20 



* See Goodman on the " Strength of Drop-forged Crane Hooks," Engineering, lxxii. p. 537. 



t Goodman on " Maximum Stresses in Crane Hooks," Minutes of Proc. of Inst, of Civil Engineers, vol. clxvii. p. 296 



