Torque control system for catheads

A system for controlling make up torque in a threaded connection where the torque is applied by a catline from a cathead, having a pneumatic pressure operated clutch, to the arm of a tong secured to one member of the threaded connection, comprising

• means to sense the tension in said catline,
• means to convert the tension sensed by said tension sensing means to ft.lb. of torque,
• comparator means including means to set a selected maximum torque setting and operable to compare the torque sensed with the maximum torque setting,
• controllable valve means controlling the application of pneumatic to said clutch,
• said comparator means being operable to actuate said valve means to a position cutting off the application of pneumatic pressure to said clutch in response to a sensed torque equal to or greater than said maximum torque setting,
• electric circuit means including and controlling said comparator means, and
• pressure sensing means operable in response to pneumatic pressure at the inlet to said valve means to inactivate said electric circuit means to prevent reactivation of said system after actuation of said valve means to cut off pneumatic pressure until pressure has been cut off to the inlet to said valve means.

A system for controlling make up torque in a threaded connection where the torque is applied by a catline from a cathead, having a pneumatic pressure operated clutch, to the arm of a tong secured to one member of the threaded connection, comprising

• electric signal means to sense the tension in said catline,
• electric means for converting a signal from said electric tension sensing means to an electric signal registered as ft.lb. of torque to convert the tension sensed by said tension sensing means to ft.lb. of torque and including means for entering the length of said tong arm for effecting the conversion of tension to torque,
• comparator means including means to set a selected maximum torque setting comprising electric means operable to compare a signal from said electric converting means with said selected maximum torque setting and to pass said signal when the sensed torque equals or exceeds said setting,
• controllable valve means comprising an electric solenoid valve actuated to cut off position in response to said signal passed by said comparator means and controlling the application of pneumatic pressure to said clutch,
• said comparator means being operable to actuate said valve means to a position cutting off the application of pneumatic pressure to said clutch in response to a sensed torque equal to or greater than said maximum torque setting,
• said solenoid valve comprises a three way valve having a first pair of openings connecting the source of air pressure to said air clutch and a second pair of openings connecting said air clutch to vent,
• said solenoid valve when inactivated connecting said first pair of openings and when activated connecting said second pair of openings,
• a first pressure sensing transducer positioned in said valve to respond to pressure in the connection from the source of compressed air,
• a second pressure sensing transducer positioned in said valve to respond to pressure in the connection from said air clutch,
• electric alarm means,
• said first pressure sensing transducer being electrically connected and operable in response to pneumatic pressure in the connection from the source of compressed air to inactivate said electric circuit means to prevent reactivation of said system after actuation of said solenoid valve to cut off pneumatic pressure until air pressure has been cut off to the inlet to said valve,
• electric circuit means including and controlling said comparator means, and
• said second pressure sensing transducer being connected to actuate said alarm means if the pneumatic pressure applied to said clutch is not cut off within a predetermined time after said sensed torque equals or exceeds said selected maximum torque setting.

A system for controlling make up and breakout torque in a threaded connection where the torque is applied by a catline from a selected one of a pair of catheads, one of which is used for make up and the other used for breakout, each having a pneumatic pressure operated clutch, to the arm of a tong secured to one member of the threaded connection, comprising

• electric signal means comprising an electrical strain gage transducer to sense the tension in said catline, including means for entering the length of said tong arm for effecting the conversion of tension to torque,
• electric means to convert an electric signal from said electric tension sensing means to an electric signal registered as ft.lb. of torque and including meter means registering said converted signal as ft.lb. of torque,
• comparator means including means to set a selected maximum torque setting and operable to compare the torque sensed with the maximum torque setting,
• said comparator means comprises electric means operable to compare a signal from said electric converting means and said selected maximum torque setting and to pass said signal when the sensed torque equals or exceeds said setting,
• separate controllable valve means for each cathead, comprising an electrical solenoid operated valve actuated to cut off position in response to said signal passed by said comparator means, controlling the application of pneumatic pressure to the respective pneumatic clutches thereof,
• said comparator means being operable to actuate a selected one of said valve means to a position cutting off the application of pneumatic pressure to a selected clutch in response to a sensed torque equal to or greater than said maximum torque setting,
• switch means for selecting one of said valve means to be controlled by said comparator means,
• electric alarm means, and
• pressure sensing means operable to actuator said alarm means if the pneumatic pressure applied to said clutch is not cut off within a predetermined time after said sensed torque equals or exceeds said selected maximum torque setting.

A system for controlling make up torque in a threaded connection where the torque is applied by a catline from a selected one of a pair of catheads, each having a pneumatic pressure operated clutch, to the arm of a tong secured to one member of the threaded connection, comprising

• means to sense the tension in said catline,
• means to convert the tension sensed by said tension sensing means to ft.lb. of torque,
• comparator means including means to set a selected maximum torque setting and operable to compare the torque sensed with the maximum torque setting,
• separate controllable valve means for each cathead controlling the application of pneumatic pressure to the respective pneumatic clutches thereof,
• said comparator means being operable to actuate a selected one of said valve means to a position cutting off the application of pneumatic pressure to a selected clutch in response to a sensed torque equal to or greater than said maximum torque setting, and
• switch means for selecting one of said valve means to be controlled by said comparator means,
• electric circuit means including and controlling said comparator means, and
• pressure sensing means operable in response to pneumatic pressure at the inlet to said valve means to inactivate said electric circuit means to prevent reactivation of said system after actuation of said valve means to cut off pneumatic pressure until pressure has been cut off to the inlet to said valve means.

A system for controlling make up torque in a threaded connection where the torque is applied by a catline from a selected one of a pair of catheads, each having a pneumatic pressure operated clutch, to the arm of a tong secured to one member to the threaded connection, comprising

• electric signal means to sense the tension in said catline,
• means to convert the tension sensed by said tension sensing means to ft.lb. of torque and comprising electric means for converting a signal from said tension sensing means to an electric signal registered as ft.lb. of torque,
• comparator means including means to set a selected maximum torque setting and operable to compare the torque sensed with the maximum torque setting,
• said comparator means comprising electric means operable to compare a signal from said electric converting means with said selected maximum torque setting and to pass said signal when the sensed torque equals or exceeds said setting,
• separate controllable valve means for each cathead controlling the application of pneumatic pressure to the respective pneumatic clutches thereof,
• said valve means each comprising an electrically actuated valve actuated to cut off position in response to said signal passed by said comparator means,
• said comparator means being operable to actuate a selected one of said valve means to a position cutting off the application of pneumatic pressure to a selected clutch in response to a sensed torque equal to or greater than said maximum torque setting,
• an electric switch for selecting one of said valve means to be controlled by said comparator means, said valve comprises a three way solenoid valve having a first pair of openings connecting the source of air pressure to said air clutch and a second pair of openings connecting said air clutch to vent,
• said solenoid valve when inactivated connecting said first pair of openings and when activated connected said second pair of openings,
• a first pressure sensing transducer positioned in said valve to respond to pressure in the connection from the source of compressed air,
• a second pressure sensing transducer positioned in said valve to respond to pressure in the connection from said air clutch,
• electric alarm means,
• said first pressure sensing transducer being electrically connected and operable in response to pneumatic pressure in the connection from the source of compressed air to inactivate said electric circuit means to prevent reactivation of said system after actuation of said solenoid valve to cut off pneumatic pressure until air pressure has been cut off to the inlet to said valve,
• electric circuit means including and controlling said comparator means, and
• said second pressure sensing transducer being connected to actuate said alarm means if the pneumatic pressure applied to said clutch is not cut off within a predetermined time after said sensed torque equals or exceeds said selected maximum torque setting.