Dissolvable tools have been introduced to the industry functioning mainly as temporary pressure bearing tools, which will dissolve themselves after operations of a planned duration to restore the original flow-path. This paper is intended to present two types of dissolvable tools; dissolvable plug and dissolvable frac ball that are used in multistage stimulations. Dissolvable bridge plugs and frac balls are now available, meaning there will be no need to drill out the bridge plug or frac balls. This is different than a composite bridge plug and can provide substantial savings in time reduction for every well. Dissolvable technology avoids any HSE issues related to plug milling/drilling. Under different temperature and salinity, the ROD (Rate of Dissolving) of dissolvable metal, Mg-Al alloy can be varied. Detailed tests, have been performed to establish a raw material selection chart based on conditions for various downhole applications. Lab tests on dissolvable tools to prove pressure rating and temperature rating. Field runs of dissolvable tools downhole have shown they hold high differential pressure, in agreement with the lab test 10K psi differential pressure rating. After the stimulation operation is concluded the dissolvable tools dissolve in a pre-designed duration downhole. We will discuss the novel experience gained from a China Shale Gas project from an operational perspective. The discussion will describe dissolvable tools raw material selection, the successful and economical dissolvable plug & perf operation that was conducted.

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