Research and Development of Downhole High Power (Ultra)Sonic Technologies and Applications

Badger Explorer ASA and its partners researched and developed technologies to generate powerful high-frequency vibrations under down-hole conditions for use in Badger Explorer tools, a new class of exploration device that will offer a cheaper and more environmentally friendly alternative to exploration drilling. Vibrations can alter the behavior of many materials -especially those composed of small particles mixed with fluids. Children learn this when they wiggle their toes to sink them into sand, or shake a sugar jar to make space for more sugar. At an industrial scale, powerful high-frequency vibrations at, and just beyond, the range of human hearing are used in a similar way to make powders and mixtures flow more easily, to compact products such as ceramics and painkillers, and to accelerate chemical reactions. We term these types of vibrations High Power (Ultra)Sound, or HP(U)S. HP(U)S's ability to make mixtures flow and compact more easily is of particular interest to us. Badger Explorer tools operate by burrowing into the subsurface and transporting the drilled waste to the top of the tool where it is compacted back into a plug. Down-hole HP(U)S will help us improve the drilling and compaction performance of our tools. In this program, we researched and developed technologies to generate HP(U)S vibrations under high temperature and pressure, building four prototype generators (transducers) and a fifth design. We also performed experiments to investigate how HP(U)S vibrations alter the behavior of materials and delivered valuable scientific knowledge. HP(U)S has many other industrial uses such as speeding up chemical reactions, welding, and making thick fluids such as oil flow more easily. We also anticipate spin-off applications from the project as it has the enabled HPUS processes in higher temperature and pressure environments that previously achievable.

This project aims to perform the research and development necessary to realize the application of High Power (Ultra)Sound downhole, and in particular, for the Badger Explorer concept. The Badger Explorer is a tool that provides an alternative to explorat ion drilling and logging. It advances through the subsurface by drilling, transporting cuttings to the rear of the tool, and compacting them into a solid plug. Excess cuttings are injected into the formation. A cable connected to the surface is spooled ou t from within the tool and embedded in the plug as the tool advances. The Badger records petrophysical logs of the formations encountered and relays this data to the surface. Implementing the Badger Concept is challenging. Drilling is hindered by the la ck of available fluid for bit cleaning, compaction by the high forces required to compress the cuttings back to near-original density, and injection by the rheology of the cuttings mixture. Altering the behavior of materials encountered during subsurfac e operations so that they flow, compact, and weaken in targeted manners would be of benefit to the Badger Explorer and the petroleum industry in general. Such capabilities would enhance electric drilling, slurry fracture injection, zonal isolation, and co mpaction processes. High-Power (Ultra)Sonic vibrations have the ability to accomplish these types of changes (e.g. Ensminger and Bond, 2010). This has been confirmed by in-house experiments. This project aims to bring this type of HP(U)S technology downho le. It will research and develop HP(U)S technology for downhole conditions, use physical experiments to characterize how HP(U)S influences formation materials under these conditions, and utilize the knowledge gained to develop example applications for the Badger Explorer.