Downhole chemical cutter

Abstract

Chemical cutting tool for use within a well bore for cutting very small diameter tubular goods. The tool has an elongated tool body having anchoring means for anchoring the tool within a conduit and a pressure generating section. A cutting section of the tool body has a longitudinal bore having at least one cutting port for expelling cutting agent. A chemical section in the tool body is between the pressure generating section and the cutting section. The chemical section includes a casing having a chamber containing a source of fluid cutting agent. The tool further comprises closure means at at least one end of the casing. The closure means comprises a diaphragm body which is inserted into one end of the casing by an interference fit and which has spaced transverse rupture diaphragms. One of the rupture diaphragms fits into the diaphragm body in an interference fit. The other rupture diaphragm may fit into the tool body in an interference fit, or may be formed integrally. The casing of the chemical section has an internal shoulder and an internally threaded box connection extending outwardly from the shoulder. A tubular body having a diaphragm, has a reduced portion which fits into the casing in the interference fit and an upset shoulder. An annular sealing ridge on the shoulder surrounds the rupture diaphragm and interacts with a metal washer to form a seal.