Abstract: Example workover vehicles for removing and installing sucker rods and tubing of completed wells include a mast having a distinctive spatial relationship with various equipment of the vehicle. The mast has a series of vertical corner posts or weight bearing derrick legs that define the mast's horizontal footprint. In some examples, a tubing storage rack is situated mostly within the footprint while a rod storage rack is mostly beyond the footprint. A robot traveling vertically along the mast transfers rods and tubing between the well and the appropriate storage rack. In some examples, the rod storage rack pivots between an extended operative position and a retracted transport position. In some examples, a robotic jib transfers rods or tubing to and from a lay-down storage area. Some example robot jibs are movable to a fully deployed position for normal operation and a stored position within the mast's footprint for vehicle transport.

Abstract: Example well servicing vehicles for removing and installing well strings (e.g., sucker rods and tubing) within wellbores provides a method for determining and logging snag points within the wellbore. In some examples, snag points are determined based on a predetermined change in cable tension, crown load strain and/or hydraulic pressure. The predetermined change is adjusted based on the current length of the well string at the time the snag occurs.

Abstract: An example robotic method for disassembling and removing a well string (e.g., a string of sucker rods or tubing within a wellbore) involves a computer controlled track and trolley system. Movement of multiple trolleys, carriages, shuttles, articulated arms and other hardware is orchestrated in a manner that minimizes cycle time and thus reduces the overall time for removing the entire well string. In some examples, upper and lower robots travel along and share a first set of tracks while an upper trolley mechanism and a main trolley travel along and share a second set of tracks. In some examples, the two sets of tracks are mounted vertically to a mast, wherein the mast is part of a workover vehicle.

Abstract: A tongs system and method for making and breaking threaded joints of a string of tubing for an oil well involves, in some examples, the use of a set of tongs with a two-speed transmission and a hydraulic system selectively operable in a high-pressure mode and a low-pressure mode. During an initial tightening period, the tongs system operates in high-gear and high-pressure for maximum speed. During a subsequent final tightening period, the tongs system operates in low-gear and low-pressure to controllably tighten the joint to a predetermined target torque. In some examples, to allow the transmission to shift speed without jamming gears, the tongs system pauses for an instant between the initial and final tightening periods. In some examples, the tongs system is interlocked with a hoist and/or other tube-holding and handling equipment.

Abstract: Just above an oil wellbore, an example circumferential displacement tool grips a threaded coupling in performing a circumferential displacement method of properly tightening the coupling to an upper sucker rod and/or to a lower one. In some examples, upper and lower joints of the coupling are tightened sequentially and independently to ensure proper circumferential displacement at each joint. In some examples, during disassembly of a string of rods being withdrawn from the wellbore, the tool can unscrew the coupling selectively from either the upper rod or the lower one. In some examples, a controller monitors the tightening or unscrewing of a joint and derives a joint signature based on a series of torque and rotation readings sampled during the make or break operations. The controller, in some examples, identifies a defective joint by comparing the joint signature to a predetermined reference.

Abstract: A method for controlling and coordinating the operation of a lifting device and a tongs device in removing and disassembling and/or installing and assembling a series of elongate members disposed within a wellbore involves sequentially sensing the presence of a series of joints and automatically triggering the lifting device and tongs device in response thereto. In some examples, the method senses the location of an upper joint to determine when the lifting device should begin decelerating prior to stopping the ascent of a lower joint at a target elevation. In some examples, the method includes control means for automatically skipping various joints.

Abstract: Example workover vehicles for removing and installing sucker rods and tubing of completed wells include a mast having a distinctive spatial relationship with various equipment of the vehicle. The mast has a series of vertical corner posts or weight bearing derrick legs that define the mast's horizontal footprint. In some examples, a tubing storage rack is situated mostly within the footprint while a rod storage rack is mostly beyond the footprint. A robot traveling vertically along the mast transfers rods and tubing between the well and the appropriate storage rack. In some examples, the rod storage rack pivots between an extended operative position and a retracted transport position. In some examples, a robotic jib transfers rods or tubing to and from a lay-down storage area. Some example robot jibs are movable to a fully deployed position for normal operation and a stored position within the mast's footprint for vehicle transport.

Abstract: A tongs system and method for making and breaking threaded joints of a string of tubing for an oil well involves, in some examples, the use of a set of tongs with a two-speed transmission and a hydraulic system selectively operable in a high-pressure mode and a low-pressure mode. During an initial tightening period, the tongs system operates in high-gear and high-pressure for maximum speed. During a subsequent final tightening period, the tongs system operates in low-gear and low-pressure to controllably tighten the joint to a predetermined target torque. In some examples, to allow the transmission to shift speed without jamming gears, the tongs system pauses for an instant between the initial and final tightening periods. In some examples, the tongs system is interlocked with a hoist and/or other tube-holding and handling equipment.

Abstract: An example robotic method for disassembling and removing a well string (e.g., a string of sucker rods or tubing within a wellbore) involves a computer controlled track and trolley system. Movement of multiple trolleys, carriages, shuttles, articulated arms and other hardware is orchestrated in a manner that minimizes cycle time and thus reduces the overall time for removing the entire well string. In some examples, upper and lower robots travel along and share a first set of tracks while an upper trolley mechanism and a main trolley travel along and share a second set of tracks. In some examples, the two sets of tracks are mounted vertically to a mast, wherein the mast is part of a workover vehicle.

Abstract: A method for controlling and coordinating the operation of a lifting device and a tongs device in removing and disassembling and/or installing and assembling a series of elongate members disposed within a wellbore involves sequentially sensing the presence of a series of joints and automatically triggering the lifting device and tongs device in response thereto. In some examples, the method senses the location of an upper joint to determine when the lifting device should begin decelerating prior to stopping the ascent of a lower joint at a target elevation. In some examples, the method includes control means for automatically skipping various joints.