Independent one-way acting hydraulic jar sections for a rotary drill string

A hydraulic jar arrangement for incorporating in a drill string for use in a well bore comprising:

• a. a first hydraulic jar section for delivering an upward jar to the drill string when it is stuck in a well bore comprising:
• 1. a first outer tubular member;
• 2. a first inner tubular member telescopically arranged and terminating within said first outer tubular member;
• 3. longitudinally spaced seals means between said first inner and outer tubular members forming a first chamber in the drill string for confining hydraulic operating fluid;
• 4. jarring surfaces on said first inner and outer tubular members for jarring contact with each other to deliver an upward jar to the stuck drill string;
• and
• 5. first hydraulic jar means formed by cooperating means on said first inner and outer tubular members within the first chamber for restraining relative longitudinal movement of said first inner and outer tubular members to an extended position, said cooperating means operable after a predetermined relative longitudinal movement between said first inner and outer tubular members to release said first inner and outer tubular members for subsequent unrestrained relative longitudinal movement therebetween until said jarring surfaces engage with each other to deliver an upward jar to the stuck drill string;
• b. a second hydraulic jar section for delivering a downward jar to the drill string when it is stuck in the well bore comprising:
• 1. a second outer tubular member;
• 2. a second inner tubular member telescopically arranged and terminating within said second outer tubular member;
• 3. longitudinally spaced seal means between said second inner and outer tubular members forming a second chamber in the drill string for confining hydraulic operating fluid;
• 4. jarring surfaces on said second inner and outer tubular members for jarring contact with each other to deliver a downward jar to the stuck drill string;
• and
• 5. second hydraulic jar means formed by cooperating means on said second inner and outer tubular members within the second chamber for restraining relative longitudinal movement of said second inner and outer tubular members to a telescoped position, said cooperating means operable after a predetermined relative longitudinal movement between said second inner and outer tubular members to release said second inner and outer tubular members for subsequent unrestained relative longitudinal movement therebetween until said jarring surfaces on said second inner and outer tubular members engage with each other to deliver a downward jar to the stuck drill string;
• c. additional spaced seal means between said first inner and outer tubular members and between said second inner and outer tubular members forming an additional chamber in each of said first and second hydraulic jar sections for confining a lubricating fluid;
• d. drive means in each of the additional chambers for connecting said first inner and outer tubular members and said second inner and outer tubular members to prevent relative rotation, while accommodating relative longitudinal movement, between said first inner and outer tubular members and between said second inner and outer tubular members respectively;
• e. means in the first hydraulic jar section to equalize pressure adjacent one end of each the first chamber and the additional chamber with the pressure in the well bore whereby an upward jarring force may be effected in the stuck drill string independently of any well bore pressure;
• and
• f. means between the second chamber and the additional chamber in said second hydraulic jar section to equalize pressure adjacent one end of each the second chamber and the additional chamber with the pressure in the well bore whereby a downward jarring force may be effected in the stuck drill string independently of any well bore pressure.

A hydraulic jar arrangement for incorporating in a drill string for use in a well bore comprising:

• a. a first hydraulic jar section for delivering an upward jar to the drill string comprising:
• 1. a first outer tubular member;
• 2. a first inner tubular member telescopically arranged and terminating within said first outer tubular member;
• 3. longitudinally spaced seals means between said first inner and outer tubular members forming a first chamber in the drill string for confining hydraulic operating fluid;
• 4. jarring surfaces on said first inner and outer tubular members for jarring contact with each other to deliver an upward jar to the drill string;
• and
• 5. first one-way acting fluid meter means in said first chamber for restraining relative longitudinal movement of said first inner and outer tubular members to an extended position, said first fluid meter means operable after a predetermined relative longitudinal movement between said first inner and outer tubular members for subsequent unrestrained relative longitudinal movement therebetween until said jarring surfaces engage with each other and deliver an upward jar to the drill string;
• b. a second hydraulic jar section for delivering a downward jar to the drill string comprising:
• 1. a second outer tubular member;
• 2. a second inner tubular member telescopically arranged and terminating within said second outer tubular member;
• 3. longitudinally spaced seal means between said second inner and outer tubular members forming a second chamber in the drill string for confining hydraulic operating fluid;
• 4. jarring surfaces on said second inner and outer tubular members for jarring contact with each other to deliver a downward jar to the drill string;
• and
• 5. a second one-way acting fluid meter means in said second chamber for restraining relative longitudinal movement of said second tubular members to a telescoped position, said fluid meter means operable after a predetermined relative longitudinal movement between said second inner and outer tubular members to release said second inner and outer tubular members for subsequent unrestrained relative longitudinal movement therebetween until said jarring surfaces on said second inner and outer tubular members engage with each other to deliver a downward jar to the drill string;
• c. additional spaced seal means between said first inner and outer tubular members and between said second inner and outer tubular members forming an additional chamber in each of said first and second hydraulic jar sections for confining a lubricating fluid;
• d. drive means in each of the additional chambers for connecting said first inner and outer tubular members and said second inner and outer tubular members to prevent relative rotation, while accommodating relative longitudinal movement, between said first inner and outer tubular members and between said second inner and outer tubular members respectively;
• e. means in the first hydraulic jar section to equalize pressure adjacent one end of each the first chamber and the additional chamber with the pressure in the well bore whereby an upward jarring force may be effected in the stuck drill string independently of any well bore pressure;
• and
• f. means between the second chamber and the additional chamber in said second hydraulic jar section to equalize pressure adjacent one end of each the second chamber and the additional chamber with the pressure in the well bore whereby a downward jarring force may be effected in the stuck drill string independently of any well bore pressure.

In a hydraulic jar for use in a drill string in a well bore:

• a. inner and outer telescopically arranged tubular members movable longitudinally relative to each other with means for connecting one end of each the inner and outer tubular members in the drill string;
• b. jarring surfaces on said inner and outer tubular members for jarring contact with each other to deliver a down jar to the drill string.
• c. spaced seal means between said inner and outer tubular members forming a first chamber in the drill string for confining hydraulic operating fluid;
• d. additional spaced seal means between said inner and outer tubular members forming an additional chamber in the hydraulic jar for confining a lubricating fluid;
• e. drive means in the additional chamber for connecting said inner and outer tubular members to prevent relative rotation, while accommodating relative longitudinal movement, between said inner and outer tubular members;
• f. hydraulic jar means formed by cooperating means on said inner and outer tubular members within the first chamber to restrain relative longitudinal movement of said inner and outer tubular members and which are operable to release said inner and outer tubular members for subsequent unrestrained relative longitudinal movement therebetween until said jarring surfaces engage with each other to deliver a downward jar to the drill string;
• and
• g. means between the first chamber and the additional chamber to equalize pressure adjacent one end of each the first chamber and the additional chamber with the pressure in the well bore whereby a downward jarring force may be effected in the drill string.