Method and apparatus for removing abandoned tubular members

A method of severing a tubular member in a marine environment, the tubular member being hollow and having a leg wall with an inside surface, said method comprising the steps of:

• a) lowering a frame within the tubular member at a selected location, the frame having multiple curved charges, each being movable between retracted and expanded positions, wherein the charges are retained in a retracted position with a pin in step “a” lowering;
• b) moving the charges to the expanded position by removing the pin so that the charges each engage the tubular member;
• c) severing the wall of the leg by detonating the explosive charges;
• d) wherein in step “b” the charges are spring biased to move to the expanded position responsive to removal of the pin;
• and
• e) wherein the frame includes a central vertical post, and upper and lower horizontal portions attached to the post.

A method of severing a tubular member in a marine environment, the tubular member being hollow and having a leg wall with an inside surface, said method comprising the steps of:

• a) lowering a frame within the tubular member to be severed and at a selected location on the tubular member, the frame having multiple curved charge housings that are movable between retracted and expanded positions, each charge housing containing an explosive charge wherein the charge housings are held in the retracted position with a removable locking member that is not an explosive device in step “a” lowering;
• b) moving the charge housings to the expanded position by removing the locking member so that they each engage the tubular member;
• c) severing the wall of the leg by detonating the explosive charges;
• and
• d) wherein in step “b” the charges are spring biased to move to the expanded position responsive to removal of the locking member.

A method of severing a tubular member in a marine environment, the tubular member being hollow and having a leg wall with an inside surface, said method comprising the steps of:

• a) lowering a frame within the tubular member to be severed and at a selected location on the tubular member, the frame having multiple curved charge housings that are movable between retracted and expanded positions, each charge housing containing an explosive charge wherein the charge housings are held in the retracted position with a removable member that is not an explosive device in step “a” lowering;
• b) moving the charge housings to the expanded position by removing the locking member so that they each engage the tubular member;
• c) severing the wall of the leg by detonating the explosive charges;
• d) wherein in step “b” the charges are spring biased to move to the expanded position responsive to removal of the locking member;
• and
• e) wherein the frame includes a central vertical post, and upper and lower horizontal portions attached to the post.

A method of severing a tubular member in a marine environment, the tubular member being hollow and having a leg wall with an inside surface, said method comprising the steps of:

• a) lowering a frame within the tubular member to be severed and at a selected location on the tubular member, the frame having multiple curved charge housings that are movable between retracted and expanded positions, each charge housing containing an explosive charge wherein the charge housings are held in the retracted position with a removable member that is not an explosive device in step “a” lowering;
• b) moving the charge housings to the expanded position by removing the locking member so that they each engage the tubular member;
• c) severing the wall of the leg by detonating the explosive charges;
• d) wherein in step “b” the charges are spring biased to move to the expanded position responsive to removal of the locking member;
• and
• e) wherein in step “a” the frame has a centering member that engages the tubular member circumferentially to center the frame.

A method of severing a tubular member in a marine environment, the tubular member being hollow and having a leg wall with an inside surface, said method comprising the steps of:

• a) lowering a frame within the tubular member to be severed and at a selected location on the tubular member, the frame having multiple curved charge housings that are movable between retracted and expanded positions, each charge housing containing an explosive charge wherein the charge housings are held in the retracted position with a removable member that is not an explosive device in step “a” lowering;
• b) moving the charge housings to the expanded position by removing the locking member so that they each engage the tubular member;
• c) severing the wall of the leg by detonating the explosive charges;
• d) wherein in step “b” the charges are spring biased to move to the expanded position responsive to removal of the locking member;
• and
• e) wherein in step “a” the frame has a centering member that engages the tubular member circumferentially to center the frame.

A method of severing a tubular member in a marine environment, the tubular member being hollow and having a leg wall with an inside surface, said method comprising the steps of:

• a) lowering a frame within the tubular member to be severed and at a selected location on the tubular member, the frame having multiple charge housings that are movable between retracted and expanded positions, each charge housing containing an explosive charge wherein the charge housings are retracted in step “a” lowering;
• b) holding the charge housings in the retracted position with a locking member that is not an explosive device,
• c) moving the charge housings to the expanded position by removing the locking member so that they each engage the tubular member;
• d) severing the wall of the leg by detonating the explosive charges;
• and
• e) wherein in step “c” the charges are spring biased to move to the expanded position.