169
OUTER BASES---15-POUNDER GUN MOUNTS.
No. 7220.
Marks, ob“i5 Diameter, ".505.
Sectional area, .20 square inch. Gauged length, 2".
Remarks.
Successive permanent set.
Initial load.
Elastic limit.
Tensile strength.
Inch.
0.
0.
Permanent
set.
Inch.
0.
0.
Successive elongation per inch.
Inch.
0.
.00010 .00025 .00035 .00030 .00010 . 00005 . 00535 .00075 .00050 .00050 .00075
Elongation per inch.
Inch.
0.
.00010 .00035 .00070 . 00100 .00110 .00115 . 00650 . 00725 .00775 .00825 . 00900
Applied loads per square inch.
Pounds.
1,000
5,000*־ 10,000 20,000 25,000 27,000 28,000 29,000 30,000
31.000
32.000 33,000 72,000
General summary.
.......................pounds.. 72,o00
...........................do... 28,000
..........................inch.. .1700
...........................do... .00115
...........................do...	.045
................................ 16.9
....................... '90.׳ from neck
granular, silky spot at circumference
17.״ ,*17.״ ...........................■
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.............................
No. 7242.
Marks, o ¿3is Diameter, ".505.
Sectional area, .20 square inch. Gauged length, 2".
Applied loads per square inch.	Elongation per inch.	Successive elongation per inch.	Permanent set.	Successive permanent set.	Remarks.
Pounds. 1,000 5,000 10,000 20,000 25.000 28.000 29.000 30.000 31.000 32.000 33.000 34.000 69,450	Inch. 0. .00010 . 00025 .00060 .00085 .00095 .00100 .00675 . 00750 .00825 .00910 .01000	Inch. 0. .00010 .00015 .00035 .00025 .00010 .00005 .00575 .00075 .00075 .00085 .00090	Inch. 0. 0.	Inch. 0. 0.	Initial load. * Elastic limit. Tensile strength.
					
					
					
					
					
					
					
					
					
					
					
General summary.
......................pounds..	69,450
.........................do...	29,000
......................  inch..	.1300
.........................do...	.00100
.........................do...	.045
.............................. 16.9
..................... 1".14 from neck
granular 50 per cent, silky 50 per cent .......................... ".13* ".13
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.............................