Drilling tool carrying vertical row of explosive charges - esp. for making gravel pack used in winning hydrocarbon(s) from earth

摘要

A cable is used to suspend a tool in a hole in the earth. The tool has a bottom head provided with an adapter and a connector holding a support. The support consists of a longitudinal row of flat zones aligned at different angles w.r.t. each other. Each flat zone has two holes, which are sepd. by a distance (d) between centres which is less than the max. dia. of the sealed envelopes of explosive charges which are fixed to the support via the holes. The charges are used in pairs, one charge being radially opposite the other, and are detonated by electric cables. Used esp. for making a large number of large dia. holes for conducting a qravel pack. A cable is used to suspend a tool in a tube forming a sheath in a hole drilled in the earth. Tool has a detector counting the joints in tubes and thus the depth; and also a head joined by an adapter and connector to a support and a tailpiece. Support carries pairs of explosive charges radially opposite each other. Support is made by flattening a steel tube 4 cm. in dia., so three flats are obtd. aligned at 90 deg. w.r.t. each other. Each flat has two fixing holes for a pair of charges.