Method and apparatus for severing tubing

Tubing cutting apparatus consisting essentially of

• a tubular housing having an upper end and a lower end;
• a first explosive charge confined in the upper portion of the housing and terminating in a convex end portion adjacent the center of the housing;
• a second explosive charge confined in the lower portion of the housing and terminating in a convex end portion adjacent the center of the housing;
• an explosive-free space at the center of the housing adjacent the convex ends of the first and second charges;
• and
• means for detonating both of the explosive charges at locations spaced axially in the housing from the center thereof.

The method of severing a tubular member along a plane extending normal to the axis thereof consisting essentially of

• configuring two explosive charges as elongate bodies terminating in protuberant, convexly shaped end portions;
• confining the two charges in an enclosing, elongate housing sized for insertion in the tubular member with the elongate bodies in longitudinal alignment, and with the convexly shaped end portions in adjacent opposed relationship wherein said convexly shaped end portions cooperate to define and maintain an open space between said charges within said housing;
• positioning the housing inside the tubular member with the convexly shaped end portions substantially in the desired plane of severance of the tubular member;
• and
• simultaneously detonating the charges by initiating the explosion thereof at points therealong substantially equidistant from the convexly shaped end portions.

Apparatus for severing a tube along a plane extending generally transversely through the walls of said tube, said apparatus consisting essentially of:

• two explosive charges each of said charges having a distal end and a proximal end;
• two detonation means for simultaneously initiating detonation of said charges at said distal ends thereof;
• and
• housing means for confining and aligning said two charges within the interior of said tube;
• wherein said two charges are axially positioned within said housing means such that said proximal ends are effectively placed in adjacent opposed relationship and cooperate to define and maintain an explosive-free air space between said charges within said housing means and said distal ends are spaced axially in said housing means from said air space;
• and wherein
• one of said detonation means is positioned at each said distal end so that upon initiation detonation waves propagate axially through each of said charges within said housing means to collide at said air space and sever the walls of said tube along a plane extending generally transversely through said air space and said walls.

Apparatus for severing thick-walled tubing from a location within the interior of said tubing, said apparatus consisting essentially of:

• an elongated housing transversely dimensioned to facilitate insertion of said housing into the interior of said tubing;
• two explosive charges confined and axially aligned within said housing each of said charges having a distal end and a proximal end, and positioned within said housing such that said proximal ends are effectively placed in adjacent opposed relationship and cooperate to define and maintain an explosive-free air space between said charges within said housing and said distal ends are spaced axially in said housing from said air space;
• two caps each said cap covering one of said proximal ends and having a configuration complimentary to said proximal end;
• and
• two detonation means each said detonation means positioned at each said distal end for simultaneously initiating detonation of said charges at said distal ends thereof so that detonation waves propagate axially through each of said charges within said housing means to collide at said air space and sever the walls of said tubing along a plane extending generally transversely through said air space and said walls.