• Drill pipe connections have went through iterative cycles of development and improvement for some time. While a primary focus of previous connection generations was to increase performance and enable use in extended-reach and deviated wells, the current land drilling paradigm—which often requires wells be drilled and completed in extremely short timeframes, with significant wear on equipment—demanded a new connection, one that would be both cost-effective and high performing. We designed our Delta™ drill pipe connection with this in mind, aiming to reduce our customer’s total cost of ownership.

    Design considerations for the Delta connection took into account the need for deeper stabbing and faster makeup; more available room for refacing; an increased bearing surface; and updated inspection criteria. After optimizing design parameters and verifying stress distribution via finite element analysis, we put the connection through extensive laboratory testing and rigorous field trials on our test rig in Navasota, Texas. Early results were extremely positive—so much so, in fact, that we were able to develop new, broader acceptance criteria for the Delta connection.

    Post-trial deployments with various operators have validated the connection’s performance, including in the difficult extended laterals now common in North American shale. The Delta connection continues to outperform the competition, achieving an overall recut rate of just 3.6% over a sizable sampling base of more than 40,000 connection inspections. The low rate of repair is roughly a quarter of that of the industry’s reference connection in this torque performance range. Pre-well torque-and-drag modeling—performed by one of our rental partners, Quail Tools—has also repeatedly confirmed the additional performance benefits of using the connection.

    To learn more about the history and development of our Delta connection and the results of early deployments with rental partner Quail Tools, read our feature "Drill Pipe" article in the August edition of World Oil magazine here.

    Published Date: 2018-08-29
    Source: National Oilwell Varco