Coiled tubing well tool and method of assembly

Abstract

A long, well tool which effectively performs as an integral part of a typical coiled tubing string and accordingly can be ran continuously into a pressurized wellbore with the same deployment equipment as used with known coiled tubing. The tool is comprised of a plurality of elements (e.g. perforating charges or logging sensors such as hydrophones, geophones, gamma ray sensors, gravity sensors, etc.) fixed at spaced, known distances from each other within a flexible housing, e.g. a length of coiled tubing.

Description

1. TECHNICAL FIELD[0001]The present invention relates to a downhole well tool which is effectively incorporated into the lower end of a string of coiled tubing and in one of its aspects relates to running a long well tool having a plurality of elements (e.g. logging sensors, perforating charges, etc.) into a pressurized wellbore without the need of specialized, pressure deployment equipment or procedures.2. BACKGROUND OF THE INVENTION[0002]It has long been routine to run a long well tool into a wellbore to carry out a particular operation. For example, it is routine to “log” a well after or during drilling to determine various characteristics of the subterranean formations traversed by the wellbore. That is, a well may be logged to determine the presence and location of any oil / gas deposits that may lie adjacent the wellbore. Some of these logging operations require taking measurements at several spaced points within the wellbore and then collating the collected data to produce the ...

AI Technical Summary

Benefits of technology

[0010]The present invention provides a long well tool (e.g. logging tool, perforating tool, etc.) which can be ran into a pressurized wellbore without requiring the time consuming and tedious operating steps typically required in such operations. Basically, the tool is one which performs as an integral part of a typical coiled tubing string and accordingly can be ran continuously into a pressurized wellbore by merely using the same deployment equipment as that used in running a standard coiled tubing string into a well. The housing of the tool is relatively flexible as is the mounting of the elements (e.g. logging sensors) within the housing so the tool, itself, can easily be coiled onto and off of a typical reel of known coiled tubing systems.

[0013]By effectively incorporating the plurality of elements into the coiled tubing, itself, long tools (e.g. 500 feet or more) can easily and quickly be run into a pressurized well using only the same deployment equipment and techniques used in running any typical coiled tubing string into a well. This eliminates the several tedious steps previously required with the running of long well tools where the tools had to be made up by joining components as the tool is being lowered through the wellhead.

Problems solved by technology

Not only is this operation time consuming, it can also lead to inaccuracies in the final log since, in many instances, it is critical not only to know the depth at which each measurement is taken but also the exact distances between the respective measurement points.

However, since the sensors are fixed in a rigid cylindrical housing (e.g. length of pipe, casing, or the like), the number of sensors that can be mounted in the rigid housing is limited since the overall length of the tool (i.e. housing) has to be kept relatively short in order to transverse deviated and horizontal wellbores typically encountered during the logging operation.

Also, there are problems in deploying “long” tools into pressurized wells; i.e. going from atmospheric pressure to the substantial higher pressures in the wellbore.

Problems arise when deploying long tools which will not fit within the lubricator.

This deployment procedure is both a time intensive and tedious job with risks associated with the rams not holding the well pressure, the slips not keeping the tool from being ejected from the wellbore, etc.

Unfortunately, logging tools using geophones, hydrophones, or multi-component gravity sensors are typically “long” tools requiring many repetitions of the above described deployment steps.

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