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sensor tools, tubewire conductor and to a memory stick to be viewed on a compatible with different types of fr- the data acquisition system (DAS). laptop. ing heads and fring panels.

The frst component in the BHA is a The logging graph can be printed off cablehead assembly, where the electri- in API format, so that checks can be

Development cal wire terminates into the downhole made on exact locations for perforat- The biggest challenges during design

Production tools and is sealed-off from any fuid or ing or setting plugs, etc. The DAS is and manufacturing centered on the pressure. The cablehead also includes a small, portable, Zone-1-rated enclo- logging tools and gauge carrier. We check valves and a ball-activated dis- sure, with push button controls, which required as large a through-bore as connect function, which releases the can easily be moved between CT units. possible in the tools, while keeping tool and the cable in the event of being the tools to a maximum OD of 2-7/8in., stuck downhole. ensuring length was kept to a mini-

The cablehead is a simpler design mum and still meeting the 10,000psi than previous “stiff wire” cableheads pressure rating requirement. and can be installed in the feld in In conjunction with Probe (a mea- about 45 minutes. surement tools and systems manufac-

Attached below the cablehead is turer), Welltools Ltd., and Wellvention a gauge carrier to house the logging Ltd., we were able to design a tool to tools. The cablehead is connected to meet all of these requirements.

the gauge carrier by a castellated quick- Aker recently completed testing the connect sub, which means there are system in a test well, which involved no additional electrical connections to running different downhole tools, make up. including motors, burning shoes,

We chose to run the logging tools in Venturi junk baskets, and fshing tools. a gauge carrier to offer protection to the This was done with the logging tools tools and make it simpler to swap out installed and allowed Aker to correlate tools during operations. against known tubing connections in

An optional lower disconnect sub the well. It also provided downhole can be installed, should the need pressure and temperature data. arise to run additional logging tools or The results proved that the sen- perforating guns below the gauge car- sors downhole do provide different rier. This allows electrical connection data trends from those traditionally through the entire BHA but provides a observed at surface and allowed Aker disconnect function so the whole BHA to operate the tools in a different man- is not left downhole in the event of ner than it would normally.

getting stuck. Several tests have also been carried

The entire BHA has a 20mm thru- out to prove the capability to pump

Aker’s Real Time Coil downhole.

bore, which allows for pumping of balls through the CT string and appli- fuid and also allows pumping of balls cable tools. The emergency downhole to activate any ball drop tools. It was disconnect systems were also tested.

Capabilities developed as a modular system to The downhole logging tools in the RTC The system has been designed to run allow fexibility to run various com- system consist of a casing collar locator in conjunction with a wide range of binations of tools depending on the (CCL), scintillation crystal gamma ray standard CT tools with a view to mak- needs of the customer. sub, dual-pressure sensor (inside CT ing it a standard deployment on all CT

The tubewire conductor is a 1/8- and in wellbore), and a fast-response operations in the future.

in. incoloy alloy-encapsulated wire, fuid temperature sensor. The system is

The RTC system will allow us to more which is installed in the bore of the rated to 175°C and 10,000psi.

accurately place tools in the wellbore

CT. This allows power and signals to The logging tools also have a built-in and gives us downhole data to make the be transmitted between the BHA and memory, with a 26-hr lithium battery correct decisions during operations.

the DAS on surface. The incoloy outer back-up. tube protects the wire from abrasive or When the cablehead and gauge car- Donald Kellock corrosive fuids being pumped through rier are installed on the CT, it results joined Aker the CT and, due to its small diameter, in a BHA length of about 14.5ft. With a Solutions in 2011 it has no effect on pump rates and still standard 18,500ft CT string, the addi- and has been allows the capability to pump balls for tional weight of having the tubewire involved in develop- activating downhole tools. installed is about 250kg, which can ing the Real Time

The surface logging DAS allows the be up to 10 times heavier in a conven- Coil (RtC) system.

CT operator to easily see all of the tional e-line cable. He has a Masters downhole parameters in the control The system is also capable of degree in mechanical engineering from cabin, and the data can be downloaded running a downhole camera and is Strathclyde University.

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