|
|
|
Exploration & Production: The Oil And Gas Review 2006 - October 2006 -
|
|
|
|
|
Order high-quality repints of any articles on this website
|
|
|
|
|
|
Historically, wireline or slickline technology has been limited to mechanical devices that manipulate tools downhole. These tools are used for a variety of purposes but include setting and pulling packers, plugs, performing drift runs, setting and retrieving memory gauges, side pocket mandrels, and moving sliding side doors.
Historical
Wireline tool strings have always been used in conjunction with gauges at surface (depth and weight) that allows the operator to see forces on the wire at surface in order to stay within wire strength specifications. The use of surface weight indicators is a common practice and is used every day in many aspects of wireline-deployed systems. The limiting factor when using surface weight indicators is that only the surface wire tension is visible. The ‘feel’ of the winch and the skill of the operator are paramount in the execution of a successful intervention.
In the event a misrun occurs due to lack of force downhole, the surface weight indicator will not supply the operator with enough information to react to the situation. The ‘feel’ factor is no longer sufficient to prevent additional misruns and as such technology was required to aid the operator in the decision-making process.
Data Stem
Impact Guidance Systems (IGS) embarked on a twoyear development strategy to develop the world’s first downhole impact sensor that could be used to aid the operator.
The systems known as ‘Data Stem’, offers the oil and gas industry a memory-based sensor capable of recording forces applied by the mechanical toolstring up to 150,000lb of impact force in a small modular bidirectional unit. The system is implemented below the mechanical jarring tool and records, at depth, the forces applied by a given toolstring design to a given device.
In the event a device cannot be deployed or retrieved, Data Stem supplies impact data charts that give visible data showing what forces were applied and what action is required to reconfigure a selected toolstring in order that adequate forces are then re-applied to the device for a successful intervention and reduce or completely negate a further misrun.
The wireline/slickline industry has been around for decades and the use and methods implemented have remained relatively unchanged for at least the past 20 years. Quick connectors and efficient roller stem have revolutionized intervention methods and success. Memory gauges have permitted the use of slickline for well-logging operations and drastically reduced operator cost, high load mechanical and hydraulic impact jars have allowed for higher forces to be applied to devices that have proven problematic and all of the above have aided in the ability of the service provider to get wire further, deeper, quicker and at higher angles than ever before with a much better success rate. So why are we still guessing as to what forces the toolstring is applying downhole?.
The primary reason is that only recently has technology caught up and we can now have electronics downhole that can accommodate temperatures up to 400o F. Only in recent years has the ability to miniaturize electronic components to fit into a small enough area to deploy down hole. Ultimately no one thought the requirement for a downhole impact sensor was needed. Misruns on slickline, whilst unsavoury, were not unusual and the reason for the misrun and possible consecutive miss-runs could be blamed, of course, on well conditions. There was generally no reason to think otherwise, until now.
Reliability
Impact Guidance Systems has spent the last 12 months performing verification tests to ensure our systems have a high degree of accuracy and reliability. Having no other base-line to work from and being the only company globally to design a downhole impact sensor, the calibration of the memory-based, battery-powered system would prove to be an exceptionally difficult task.
|
|
|
|
|
Download PDF