Mechanical Engineering ETDs

Publication Date



This thesis examines the use of explosives to collapse metal pipes from an applications point-of-view. A particular system is studied, both theoretically and experimentally, in order to facilitate the future design of such closures with the least possible physical testing. The calculations are based on a rigid-perfectly plastic model of the observed deformations of the tubes, and on various assumed am derived properties of the metal and sheet explosives under the dynamic conditions of closure. A computer program has been devised which simulates the actual motion of a pipe during collapse. Experimental work involved actual test firing of aluminum cylinders ranging in size from 2.5 in. O.D. to 20 in. O.D. with diameter to thickness ratios of about 20 to 1. Some of the experiments studied performance characteristics of systems which were scaled from one size to another with geometric similarity, and the rest of the experiments were parameter studies in which single variables were changed for each series of tests. The results of the tests indicate that scaling works very well as a method of predicting performance if sufficient attention is given to the dimensions and physical properties of the assemblies prior to firing. The data from most of the tests are compared graphically with the computer simulation and indicate a prediction error of less than 10% within the range of the tests.

Degree Name

Mechanical Engineering

Level of Degree


Department Name

Mechanical Engineering

First Committee Member (Chair)

William Ernest Baker

Second Committee Member

Charles Gilbert Richards

Third Committee Member

Howard Linn Schreyer

Document Type