Patent 7159657 was granted and assigned to Schlumberger on January, 2007 by the United States Patent and Trademark Office.
The loading tube comprises cups forming cup cavities for enclosing an explosive charge within each of the cups. The loading tube has ridges and valleys providing longitudinal and lateral strength to the loading tube. The loading tube is constructed of a formed material such as paper pulp, high-density polystyrene, plastic or sheet metal.