Foam cementing is commonly used for cementing in a shale gas well, while perforation after casing set is often for well completion.

页岩气固井主要采用泡沫水泥固井技术，完井方式以套管固井后射孔完井为主。

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There is also a display, just you don't see it until you nudge the volume up, or change the audio source etc, as it's set behind the casing.

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Buttons set into the elegant metal casing allow you to adjust the volume, select music titles, take phone calls and activate voice control or personal assistant features.

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