Abstract: A novel system controls accurately the torque applied to threaded connections by a cathead operating on a tong arm, usually a manual tong. A strain gage/transducer in the catline measures the pull on the tong arm and applies a signal to an electric meter having an adjustable switch/indicator for setting tong arm length to convert the signal to a reading of ft. lb. torque on the meter. a continuous strip chart records the torque and a recall circuit permits recall of the peak torque recorded on the meter after shut down. A thumb screw switch/indicator sets the selected maximum torque and a comparator trips the circuit when the torque exceeds the setting. The trip circuit energizes a solenoid on a three-way valve controlling the supply of air to an air clutch for the cathead. On actuation, the valve moves from a position directing air pressure to the clutch to a position dumping the air pressure from the clutch to stop tensioning of the catline by the cathead.