Abstract: A packing unit is provided for use with a well having a reciprocating pump and polished rod. Packing assembly seals, a barrier fluid and a pressure transmitter cooperate with housed components to regulate the pressure on either side of a first packing sub-assembly and to pressure one side of a second packing sub-assembly. The barrier fluid is contained above the first packing sub-assembly and below the second packing sub-assembly with well fluids and accompanying pressures being contained below the first packing sub-assembly, such that, if leakage occurs, relatively clean barrier fluids are leaked instead of well fluids. The well fluids pressure and barrier fluid pressure are substantially balanced across the first packing sub-assembly. The first packing sub-assembly and second packing sub-assembly include components allowing their respective packing seals to move with, and remain sealed against, the polished rod when it deviates angularly or translationally from the initial vertical orientation.

Abstract: A secondary packing arrangement is provided for use with a well having a reciprocating pump and polished rod, and in combination with a stuffing box, the stuffing box being modified. Packing seals, a barrier fluid and a pressure transmitter cooperate with modified stuffing box components to regulate the pressure on either side of a packing seal. The barrier fluid is contained above the packing seal, with well fluids and accompanying pressures being contained below the packing seal, such that if leakage occurs, relatively clean barrier fluids are leaked instead of well fluids. The pressure across the packing seal is substantially balanced across the packing seal, or the well fluid side pressure is less than the barrier fluid side, thus reducing the occurrence of leakage and extending the life of the packing seal. Sources for the well fluids cooperating with the pressure transmitter include the well's flow line and casing.

Abstract: A well penetrator consists of a number of hydraulic fluid control components and a carriage carrying a hydraulic motor and a mill bit supported in a housing which is moveable down a well casing. The control components cause the carriage carrying the mill bit to be indexed up a predetermined distance relative to the well casing and then extended gradually into contact with the well casing while being rotated by the hydraulic motor. After the mill bit completes a hole through the well casing, the hydraulic components index the mill bit back down to its starting position and align a nozzle on the outer end of a high pressure lance with the opening in the casing to direct fluid from the nozzle as the lance is moved outwardly through the hole in the casing drilled by the mill bit.

Abstract: A weak point element for a cable head comprising a tubular ring having a circumferentially extending zone of reduced tensile strength between the ends thereof. Novel cable head assemblies which substantially isolate the weak point element from other than tensile stress are also disclosed.