Joining metal tubes

Abstract From the Canadian patent

Joining Metal Tubes", A metal tube is expanded by means of an explosive charge into engagement with a surrounding tubular metal member which is supported externally by a surrounding metal die member spaced from the metal member, the intervening space being filled with a shock transmitting liquid such as water. The metal die member is readily separate from the expanded tube and is reusable indefinitely without maintenance. Its use is, therefore, more economical than the split die hitherto used. The method is especially useful for expanding large diameter tubes, for example, expanding oil-well drill pipes into pipe coupling members.