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7-INCH B. L. SIEGE HOWITZEBS.
Tube.
No. 7322
Marks, c:kl r Diameter, ".505.
Sectional area, .20 square inch. Gauged length, 2".
Initial load.
Elastic limit.
Tensile strength.
Permanent set.	Successive permanent set.
Inch. 0. 0.	Inch. 0. 0.
	
	
.00005	.00005
.00005	0.
	
	
	
	
	
	
	
	
	
Successive elongation per inch.
Inch.
0.
.00015 .00020 .00035 .00040 .00015 . 00015 .00010 .00030 .00010 . 00005 .00655 . 00050 .00125 . 00105 . 00145
Elongation per inch.
Inch.
0.
.00015 . 00035 .00070 .00110 .00125 .00140 . 00150 .00180 .00190 .00195 .00850 . 00900 . 01025 .01130 .01275
Applied loads per square inch.
Pounds. 1,000 5,000 10,000 20,000
30.000
35.000
40.000
42.000
50.000
53.000
54.000
55.000
56.000
57.000
58.000
59.000 87,400
General summary.
Tensile strength per square inch of original section............................pounds.. 87,400
Elastic limit per square inch of original section................................do. 54,000
Elongation per inch after rupture...............................................inch! ] . 2500
Elongation per inch under strain at elastic limit................................do.!! . 00195
Reduction in diameter at point of rupture........................................do'. '. . ' . 165
Reduction in area after rupture, per cent of original section.............. * ’'	54 6
Position of rupture........... 4-............................................... ".90 from neck
Character of broken surface.....................................................silky, oblique
Elongation of inch sections......................................................".’36*, ".14
H. Doc. 508-----3