Cam style anti-rotation key for tubular connections

An anti-rotation key for insertion in a pocket formed on an outer surface of a male threaded connector, the pocket having a base and first and second side walls on opposite sides from and protruding outward from the base, the key comprising:

• a lower inner side portion for contact with the base of he pocket:
• an array of teeth on a lower outer side portion for biting into an inner wall of a female threaded connector;
• first and second side edges, each side edge joining the lower inner side portion with the lower outer side portion, the first side edge defining a pivot point such that relative motion between the male and female threaded connectors in a loosening direction causes the key to pivot about an engagement of the first side edge with the first side wall and bite more deeply into the inner wall of the female threaded connecter;
• and
• upward and downward-facing shoulders on an upper outer side portion, the shoulders being spaced apart from each other for receiving an engagement member of an installation tool to apply upward and downward forces to the key.

A threaded connection between tubular members, comprising:

• female connector having internal threads, a rim, and an inner wall extending from the internal threads to the rim;
• a male connector having external threads that engage the internal threads of the female connector;
• a pocket formed on an outer surface of the male connector, the pocket having an outward-facing base and side walls on opposite sides of and protruding outward from the base;
• an anti-rotation key having a lower inner side portion for contact with the base of the pocket;
• an array of teeth on an lower outer side portion of the key for biting into the inner wall of the female connector when the key is installed in the pocket;
• first and second side edges on the key, each side edge joining the lower inner side portion with the lower outer side portion, the first side edge being configured to be at an angle relative to first side wall of the pocket upon initial installation, so that relative motion between the male and female connectors in a loosening direction causes the key to pivot about an engagement of the first side edge with the first side wall and bite more deeply into the inner wall of the female threaded connector;
• a first curved corner at an intersection between the first side edge and the lower inner side portion of the key;
• and wherein
• the intersection between the base and first side edge of the pocket lacks a curved corner with a radius the same as the first curved corner.

A method of preventing female and male connectors from unscrewing, comprising:

• forming a pocket formed on an outer surface of the male connector, the pocket having an outward-facing base and first and second side walls on opposite sides of and protruding outward from the base;
• providing an anti-rotation key having a lower inner side portion, a lower outer side portion with an array of teeth, and first and second side edges on the key, each side edge joining the lower inner side portion with the lower outer side portion, curved corner at the intersection between the first side edge and the lower inner side portion, defining a pivot point, and wherein the intersection between the second side edge and the lower inner side portion is asymmetrical with the curved corner;
• forcing the key into the pocket, easing the teeth to bite into an inner wall of the female connector, the first side edge of the key being formed such that an angular clearance exists between the first side edge of the key and the first side wall of the pocket upon initial installation;
• and,
• in the event loosening movement begins to occur, causing the key to pivot about an engagement of the curved corner with the first side wall and bite more deeply into the inner wall of the female threaded connector.

An apparatus for preventing loosening engagement between is threaded female connector and a threaded male connector, the male connector having a pocket formed on an outer surface thereof, the apparatus comprising:

• an anti-rotation key having a lower portion for insertion into the pocket and into engagement with an inner wall of the female connector;
• a key profile formed on an upper portion of the key;
• a connector profile formed on the female connector;
• a tool having a key engaging portion that releasably engages the key profile and a connector engaging portion that releasably engages the connector profile;
• and
• the tool having a power mechanism that when energized moves the key engaging portion and the connector engaging portions closer toward each other to press the key into the pocket.

A method for inserting an anti-rotation key into a pocket between a threaded female connector and a threaded male connector, the method comprising:

• providing a key profile on an upper portion of the key;
• forming a connector profile on the female connector;
• providing a tool having a key engaging portion, a connector engaging portion and a power mechanism to cause the key engaging portion and connector engaging portions to move toward each other;
• inserting the key engaging portion into the key profile and the connector engaging portion into the connector profile;
• and
• energizing the power mechanism to move the key engaging portion toward the connector engaging portion, thereby pressing the key into the pocket.