Measurement of projectile energy and velocity requirements for the disruption of unexploded ordnance

Abstract

This paper details the design and fabrication of a disrupting test rig for measuring the energy required to separate the fuze from the casing of unexploded ordnance (UXO), also called disrupting the device. Preliminary tests were conducted using an explosive disrupting tool and the energy for disruption relative to input kinetic energy was estimated and used to design a test rig with suitable energy to ensure disruption. The disrupting test rig operates on the same principle as a Charpy Notch testing machine, and can deliver up to 3kJ of kinetic energy with its 3m long and up to 137kg mass pendulum arm. A sliding fixture mechanism provides kinematic constraints to allow the fuze body to be pulled out of the casing by the projectile. Measurements taken with the disrupting rig show that disruption can be achieved with as little as 1.5kJ of kinetic energy, assuming the casing is rigidly fixed to ground during disruption. This work will inform further development of a non-explosive tool to replace existing explosive disrupting tools.