摘要 |
A stage cementer and inflation packer apparatus. The apparatus comprises a mandrel with an external closing sleeve and an operating sleeve interlocked therewith. Below the operating sleeve is an opening sleeve. The opening sleeve is mechanically acutated by a pump-down plug in a plug-operated embodiment or by a differential pressure acting on the opening sleeve in a hydraulically operated embodiment, to actuate the opening sleeve to allow inflation of the packer element. A back check valve prevents the packer from deflating. After the packer is inflated, additional pressure is applied which ruptures a rupture disc to open a port to the well annulus above the set packer element. Cementing may be carried out through this port, and after the cementing operating, a plug engages the operating sleeve to move the operating sleeve in the external closure sleeve, thereby closing the cementing port. After cementing is complete, the center components of the apparatus may be drilled out, leaving the external closure sleeve to permanently seal the cementing port.
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