A plug of cement or similar material placed as a slurry in a specific location within the wellbore and which has set to provide a means of pressure isolation or mechanical platform.

在井筒中以浆的形式置于某特定位置然后凝固的水泥或类似材料所成的塞子，它们在凝固后能隔离压力或提供机械平台。

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With a one-head platform design and fewer mechanical parts, the reliability and acoustic features of the Spinpoint F4 have been improved.

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According to reports from the AP and a press release on the Geokinetics website, the men had initially evacated the platform on a liftboat, which can be lowered and raised from the rig by mechanical pulleys.

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