摘要 |
<p>An apparatus and method for maintaining the pressure of a well fluid sample as the sample is transported to the well surface from a downhole wellbore location. The invention collects a formation fluid sample under pressure. The fluid sample is further pressurized with a traveling piston powered by the hydrostatic wellbore pressure. The pressurized formation fluid sample is contained under high pressure within a fixed volume chamber for retrieval to the well surface. Multiple collection tanks can be lowered into the wellbore during the same run to sample different zones with minimal rig time. The tanks can be emptied at the well surface with an evacuation pressure so that the fluid sample pressure is maintained above a selected pressure at all times.</p> |