A new logging tool that is will identify the free point in drill collars, drill pipe, tubing, or casing has been developed and field tested. The tool is commercially available in the wireline service sector for drilling support and well abandonment operations. Unlike previous free point methods, which used strain measurements of the pipe obtained as a series of stations with and without the application of pipe stretch or torque at each station, this new method is simply overlay of two logging passes. The first logging pass is recorded with the pipe in a neutral weight condition, and the second logging pass is recorded with tension or torque applied to the pipe. The tool utilizes the property of steel called magnetostrictive effect. When a mechanical stress is applied to the steel, the magnetization of the material is modified. Thus when torque or tension is applied to the pipe that is free to move, their magnetization will change. If the pipe is not free to move their magnetization will remain the same. The tool has been successfully tested in steel alloys that have minimal magnetic properties. This new logging tool has many advantages over legacy free pipe determination methods. First, from a rig safety standpoint, the application of pipe stretch, or torque is applied only once for a few minutes for the logging pass. With legacy free point methods numerous stationary measurements were required, with the pipe being stretched/torqued at each station. Since determination of free point is a comparison of two logging passes, real time operations and 24/7 satellite communications allow remote based operator and service company pipe recovery experts to be involved with the well site decisions. While this new technology uses a comparison of two logging passes, well site operations is not dependent on a pipe recovery expert with extensive hands on experience to be on location, or delays waiting for pipe recovery experts to arrive on location. This benefit is extremely important with the aging of the industries workforce. The small diameter logging tool is run centralized, and does not require weight bars added to the tool for slip engagement, this shortens the length of the tool string and simplifies e-line rig up procedures. Introduction Previous generation free point tools utilized strain gauge measurements which detected the stretch or rotation of the drill sting when the free point tool was mechanically anchored in the drill sting and force applied to the pipe. The determination of the free point required many stationary measurements over the estimated stuck point region with the drill string in a neutral condition and then again with either tension, or torque being applied during each recording. Mechanical slip engagement of the strain gauge sensor in the vertical and azimuthal planes is critical. This method often requires many hours of rig time and the talents of a highly skilled free point logging expert. The tool utilizes the property of steel called magnetostrictive effect1. When a mechanical stress is applied on steel material; the magnetization of the material is modified. When torque or tension is applied to the pipe that is free to move, their magnetization will change. If the pipe is not free to move their magnetization will remain the same.

The identification of the free point in drill collars, drillpipe, tubing, or casing is critical for successful drilling recovery or abandonment operations. A new logging tool, available in the wireline service sector, has been developed and field tested that will help to cost-effectively identify a free point. The tool uses the property of steel called the magnetostrictive effect. When stress is applied to steel, the magnetization of the steel is modified. The procedure using the new tool requires two logging passes. The first logging pass records magnetization information about the pipe with the pipe in a neutral weight condition. The second logging pass records magnetization information with tension or torque applied to the pipe. When torque or tension is applied to pipe that can be stretched or torqued, its magnetostrictive properties change. If a section of the pipe cannot be stretched or torqued, magnetization effects remain unchanged. On this basis, the free point (the transition from pipe that can be stretched or torqued to pipe that cannot) is easily detected by comparing two logging passes. Previous free point determination methods required a series of stationary measurements with the pipe in a neutral weight condition, the application of stretch or torque, and the presence of a highly skilled pipe recovery expert on location. The new method simply involves an overlay of two logging passes before and after the pipe has been stretched or torqued. The tool has been successfully tested in steel alloys with minimal magnetic properties.This new logging tool has significant advantages. First, from a safety standpoint, the application of pipe stretch is applied for only a few minutes between logging passes, whereas legacy methods required numerous station measurements with the pipe being stretched. Secondly, because the determination of a free point requires a comparison of logging passes, real-time operations with constant satellite communications readily permits remotely-based operator and service company pipe recovery experts to be involved with plans for freeing the pipe. The new technology is independent of a highly skilled on-site pipe recovery expert and the delays associated with waiting for the expert to arrive on location.The tool is small in diameter, run centralized, and does not require weight bars added to the tool for slip engagement. These features shorten the length of the tool string and simplify e-line rig-up procedures. The short tool length has advantages in deviated well conditions in which pump down free point tool deployment may be required.

The Halliburton Free Point tool is a game-changing technology in the determination of the free point/stuck point in support of drilling and well abandonment operations. The identification of the free point in drill collars, drillpipe, tubing, or casing is critical for successful drilling and pipe recovery or well abandonment operations. A new logging tool is available that will cost effectively identify the free point. Case histories have shown rig time reductions in excess of 50% when compared to legacy free point methods. The tool uses the property of steel called the magnetostrictive effect, by which the magnetization of the steel is modified when it is subjected to stress.The procedure for using the new tool requires two logging passes. The first logging pass creates a small magnetic field on the pipe and records the pipe magnetization information with the pipe in a neutral weight condition. The second logging pass records the magnetization information after tension or torque has been applied to the pipe and released. When torque or tension is applied to pipe that can be stretched or torqued, the magnetostrictive properties of the pipe change. If a section of the pipe cannot be stretched or torqued, the magnetization effects remain unchanged. On this basis, the free point is easily detected by comparing two logging passes, the first pass is recorded with the pipe in a neutral weight condition, and the second logging pass is obtained after the pipe is momentarily stretched or torqued. In near-vertical wells, traditional e-line gravity deployment is used. In highly deviated or horizontal wells, either pump down or tractor conveyance can be used.This new logging tool provides significant advantages from a safety standpoint; the application of pipe stretch is used for only a few minutes between logging passes. Legacy methods required numerous station measurements with the pipe being stretched. These station measurements consume rig time and can create possible HSE events because the pipe must be pulled/stretched or torqued above the neutral weight condition at each stationary measurement point. Also, because the determination of a free point with this new tool utilizes a comparison of two logging passes, real-time operations with continuous satellite communications readily enables the involvement of remotely-based pipe recovery experts with the pipe recovery planning and execution for freeing the pipe. The new technology is independent of a highly skilled on-site pipe recovery expert and the delays associated with waiting for the expert to arrive on location.The tool is small in diameter and is run centralized; it does not require the addition of weight bars for slip engagement. These features shorten the length of the tool string and simplify e-line rig up procedures. The short tool length provides advantages in deviated and horizontal well conditions in which pump down free point tool deployment may be required.The tool design incorporates safe electronic circuitry which enables explosive devices, such as strin...

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