The global demand for energy has led to an industry focused on increasing process efficiency with respect to innovative techniques for hydraulic fracturing stimulation. One such innovative process is coiled tubing (CT) deployed pinpoint stimulation. Pinpoint multistage fracturing with hydrajetting perforation technique is a solution that enables fracture placement in virtually an unlimited number of fracturing stages in long lateral sections, with a single trip into the wellbore. The evolution of pinpoint stimulation technology and its benefits have been recognized in many papers published along the years.In some variations of the pinpoint stimulation technique, the bottomhole assembly (BHA) is activated by ball drop and reverse circulation of the ball. This process has been improved with a new generation design of the BHA, which renders the operation capable of being entirely controlled remotely from the surface using movement of the CT string. The ball drop activation is eliminated. This allows real-time, on-demand control of the tool setting. Based on traditional proven pinpoint solutions and adopting this new way of well stimulation, the pinpoint multistage fracturing method has become more efficient. This improved BHA, in conjunction with a proprietary pinpoint stimulation process, can help reduce water consumption on location and horsepower requirements, reduce idle time between fracturing treatments, reduce pump time per stage, and help prevent ball drop difficulties, all without having to make changes to the fracturing spread, equipment, and CT on location.The improved BHA enables hydrajet perforation, hydraulic fracturing using real-time downhole proppant concentration control, and proppant plugs to be set for zonal isolation. Additionally, multicycle sequences can be repeated in long lateral and vertical wells. It also helps assist centralization of the BHA during perforating operations to help maintain appropriate jet standoff distance. This paper presents the development approach of the aforementioned improved BHA, and a means to manipulate it from the surface. Validation during field testing is also outlined.

There are many ways to stimulate an unlined openhole horizontal well using acid. The simplest way is to just pump acid into the well (i.e., bullhead) without placement control. However, this can often be ineffective. Although still used, such approaches can create massive enlargements at the entry point or high injectivity area, thus causing ineffective treatments and re-entry issues. Wellbore collapse often follows. The use of coiled tubing (CT) as a "pin-point" delivery method is therefore preferred. Using CT allows dispersal of the acid either uniformly or intermittently along the lateral, as desired. CT also allows acid washing to be performed, which is another common process that can improve stimulation without much additional expense to the operator. Using a jetting tool with many jets, acid can be sprayed onto the wellbore wall, and the active agitation caused by the acid-wash process increases the chemical reactivity of the acid at the desired locations. Another beneficial approach of using CT is the hydrajet assisted acid fracturing (HJAAF) method. With focused jetting of acid at much higher pressures, the process initiates microfractures in the wellbore walls. When etched with acid, this approach effectively bypasses near-wellbore (NWB) damage much deeper than common washes, thus providing much better results. Further modification of the process by exerting high annular pressures offers the capability of delivering medium to large fractures. This paper discusses two HJAAF processes uniquely combined into one process used in two large horizontal wells. Because of the large dimension of the inner diameter (ID) of the wells combined with the small production tubing the tool must pass through, the implementation had to be further improved by using a unique jetting mechanism, which positioned the jet nozzles closer to the target. Actual results of such stimulations are presented.

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