| 摘要 |
<p>Packoff leaks in an unaccessible wellhead are monitored by a first pressure-sensitive detector positioned below the packoff seal. The space above the packoff seal is isolated from the inner bore of the casing, and fluid under pressure is applied above the seal to create a pressure differential across it. Any leakage through the seal is detected by a wise in pressure at the first detector. A second detector, coupled to the space above the seal, monitors the pressure above the seal. -la-</p> |
