The Testing of Commercial Glassware
JSGT_1932_V16_T005_T017
Tests applied to commercial glassware (bottles) are discussed in a general way. No single test can be applied to give a measure of the general strength of such articles; all known methods of testing merely indicate the strength in one part of the bottle. In thermal endurance tests failure always begins in the side-wall near the base; breakdown due to internal pressure begins in that part of the bottle where the stress is concentrated by reason of the shape; impact tests are, of necessity, applied at one point only. A thermal endurance test is described in which the inaccuracies of operation arc so reduced that a reasonably accurate measure of the thermal endurance can be obtained with as few as 20 bottles.
J. B. Murgatroyd