613 
43 
3940 
Ib/in@ 
ee 800 x Ig Seen 650 x10°% sec. zal 
Figure 26a - Record Obtained with a TMB Figure 26b - Record Obtained with a Gage Supplied 
Tourmaline Pressure Gage by the Underwater Explosives Research Laboratory 
Figure 26 - Pressure-Time Oscillograms Obtained 
with Two Tourmaline Gages in Open Water 
150 grams of tetryl 3 feet from the gage was used in each of the two explosions. 
TABLE 5 
Peak Pressure and Duration of Explosions as Registered 
by Tourmaline Piezoelectric Gages 
The distance from the gages to the charge was 36 inches, plus or minus 1 inch. 
Peak Pressure 
pounds per 
square inch 
Duration 
microseconds 
Number of 
Gage Records 
TMB* 3140 + 110 
UERL** 3010 + 120 
3840 + 140 
3840 50 
3740 + 125 
3880 65 
Ae line Ike lhe IRE IEE 
m4 mM Ww F OV 
Wns oO M OW NM 
sf 
ae 
a 
+ 
a5 
* nTMB" refers to a Taylor Model Basin gage. 
* WWERL" refers to a gage belonging to the Underwater Explosives Research Laboratory. 
performance when used with explosions of 1 ounce or less of tetryl.* In ad- 
dition a comparison of the records obtained with tourmaline gages with those 
of the quartz and glass gages has been undertaken. These investigations are 
still in progress, and the results will be given in a subsequent report. Ex- 
perience in these tests has shown clearly that the task of obtaining valid 
pressure-time records of explosions is greatly complicated when small charges 
are employed. For reasons set forth elsewhere in this report, the shorter 
* r 
The upper limit of 1 ounce was imposed by the fact that these tests were to be performed at the Taylor 
Model Basin, where facilities for larger explosions were then not available. 
