12-INCH STEEL В. L. RIFLED MORTARS.
58
Tube.
No. 7406.
i\/f l 19218 B!
Marks, bt2 m Diameter, ".564.
Sectional area, .25 square inch. Gauged length, 3".
Remarks.
Initial load.
Elastic limit.
Tensile strength.
Permanent set.	Successive permanent set.
Inch. 0. 0.	Inch. 0. 0.
	
	
do	do
	
	
	
	
	
	
	
Successive elongation per inch.
Inch.
0.
. 000100 .000233 .000334
000333׳. 000167. 000166. 000200. 007134 . 000833. 001067. 001100. 000900.
Elongation per inch
Inch.
0.
.000100 . 000333 . 000667 . 001000 .001167 .001333 .001533 . 008667 .009500 . 010567 . 011667 .012567
Applied loads per square inch.
Pounds. 1,000 5,000 10,000 20,000
30.000
35.000
40.000
45.000
46.000
47.000
48.000
49.000
50.000 81,680
General summary.
.pounds.. 81,680
____do... 45,000
...inch..	.2133
....do... .001533
....do...	.154
......... 47.2
.. ".70 from neck
......... silky
... ".13,".15,".36*
Tensile strength per square inch of original section....
Elastic limit per square inch of original section.......
Elongation per inch after rupture.......................
Elongation per inch under strain at elastic limit.......
Reduction in diameter at point of rupture...............
Reduction in area after rupture, per cent of original section
Position of rupture.....................................
Character of broken surface.............................
Elongation of inch sections.............................