Summary A mechanism for conveying logging tools inside drillpipe has been developed that reduces the risk and cost of acquiring openhole formation evaluation data in high-angle wells and bad hole conditions. The measurement string is housed inside drillpipe, where it is protected while running in, and pumped into open hole close to final depth. Wireline tools are used for data-quality reasons, but the wireline has been eliminated, giving time, access, and well-control advantages relative to wireline pipe-conveyed logging (PCL). It is an alternative to the formation evaluation element of logging while drilling (FE-LWD), where steering decisions do not rely on real-time petrophysical analysis, particularly when the risk to the bottomhole assembly (BHA) is high. The system's ability to acquire data while conditioning the hole contributes to its efficiency and is advantageous in bad hole conditions. A 1.4-km horizontal test loop was constructed to help develop and prove the tool deployment and signaling mechanism. Insights gained during this process resulted in the development of novel payload delivery seals—key components in the system. Formation evaluation data have been acquired in 220 wells; they include horizontal wells for which other logging solutions are unattractive for reasons of accessibility and/or cost. Knowledge gained from the interpretation of these data sets has influenced completions in some wellbores and guided remedial action in others.

Obtaining log data from horizontal wells has in the past been considered a very difficult and expensive task. Added to this is the question as to whether log data presented any value as far as reservoir understanding, production enhancement or completion techniques were concerned. The perception that the capital expense of logging cannot present an economic return has resulted in a small minority of horizontal wells being logged. Reeves Wireline has used the Compact Memory Logging system for a number of clients where there has been a clear demonstration of the value of logging. Introduction While the operational logistics of obtaining log data from the horizontal section of a well has improved in the last few years the understanding that the data can justify the expenditure is lagging far behind. The methods available to obtain data include MWD, L WD, wet connect pipe conveyed wireline logging and Compact Memory wireless logging. Each method offers its own benefits. These range from providing lithology information while drilling to identifying lithology, rock parameters and fluid interfaces. Although this information can be readily obtained, the economic justification for anything beyond geosteering seems to be a cloudy issue. The benefits of logging will be discussed and in particular, examples of specific data obtained from Reeves Compact Memory Logging (CML) pipe conveyed suite of tools. Reeves Wireline Services has been utilizing wireless pipe conveyed Compact Memory Logging (CML) services for a number of different operators for over two years. A full suite of log data can be obtained that includes array induction (shallow, medium and deep responses), dual spaced neutron and photo density porosity, Pe, gamma ray, compensated sonic and hole size caliper. The smaller size, ease of conveyance and unprecedented bend radius capability of Reeves Compact Memory Logging tool string is ideal both operationally and economically for newly drilled horizontal wells as well as previously drilled wells that may require remedial assessment.

TX 75083-3836, U.S.A., fax 01-972-952-9435. AbstractA mechanism for conveying logging tools inside drill pipe has been developed that reduces the risk and cost of acquiring open hole formation evaluation data in high angle wells and bad hole conditions. The measurement string is garaged inside drill pipe where it is protected while running-in, being released into open hole close to final depth. Wireline tools are used for data quality reasons, but the wireline has been eliminated, giving time, well access and well control advantages relative to wireline pipe conveyed logging. Over shallow, long horizontal intervals the time savings are substantial because wireline re-latching is eliminated, and pipe is run-in at tripping speed. The ability to circulate over and around the tools means that logging and hole cleaning trips can be combined to give further time reductions. Cost and data quality advantages have been demonstrated relative to logging-while-drilling in wells where real-time formation evaluation data is not used to guide the drilling process.A 1.4-Km test loop constructed during the development phase proved the tool deployment sequence can be controlled and monitored using mud pressure. It enabled the design to be refined before being run in real well environments, and resulted in the development of novel payload delivery seals -a key component in the system.Using the new method, formation evaluation data has been acquired in horizontal wells that would not have been logged previously for reasons of accessibility and/or cost. Knowledge gained from the interpretation of these data sets has influenced the installation of completions in new wellbores, and guided remedial action in others.

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