Collapse of Short Thin Tubes. 



Table I. 



"One-inch" Steel Tubes. Inside diameter *942 inch 



563 



Length 



t/d. 



Pressure of Collapse. 



Number of 



in inches. 



lb. per sq. in. 



Lobes. 



1-72 



•0245 



2490 



4 



1-74 



•0190 



1600 



3 or 4 



1-78 



•0150 



1030 



3 or 4 



1-78 



•01 



420 



4 



2-63 



•0245 



2060 



3 



2-63 



•0190 



1180 



3 



2-63 



•0150 



670 



3 



2-63 



•010 



200 



3 



369 



•0245 



1390 



2 or 3 



369 



•0190 



800 



3 



3-69 



•0150 



550 



3 



3-69 



•010 



120 



3 



3-72 



•0225 



1170 



3 



5-63 



•0245 



920 



2 



563 



•0225 



730 



2 



£.63 



•0190 



520 



2 



5-63 



•0150 



320 



2 



563 



•010 



115 



2 



5-5 



•0227 



675 



3 



75 



•0245 



900 



2 



7-59 



•0225 



710 



2 



7-56 



•010 



50 



2 



7-44 



•015 



210 



2 



7-62 



•015 



190 



2 



762 



•019 



420 



2 



9-6 



•0245 



900 



2 



956 



•0225 



625 



2 



9-6 



•019 



440 



2 



956 



015 



150 



2 



11-6 



•0245 



750 



2 



1163 



•0225 



600 



2 



* 11-63 



•019 



375 



2 



11-6 



•015 



145 



2 



(i£ any) in the above interpolation and corrections. We 

 note : 



(1) The curves for different thicknesses and diameters are 

 all similar in shape. Thus the series of curves for the 1-inch 

 tubes and that for the 2-inch tubes show the same character- 

 istics. The very thin tubes show the greater variations, but 

 this is to be expected owing- to the difficulty in getting 

 uniformity in thickness and material for thin tubes. 



(2) By taking the point for the length of six diameters, 

 and drawing an hyperbola through this point, using the 



equation p ! = p-f> anc ^ taking p as the collapsing pressure at 



the length of six diameters, there is, in most cases, a satisfactory 



2Q2 



Iji! 



ir 1 



