When performing indirect displacements where differential pressures are created due to varying fluid weights or a liner top is required to be tested to an equivalent mud weight (EMW), it is recommended to perform the integrity test before swapping fluids with kill weight mud in the wellbore. The Inflow Tech™ allows this test to be performed in kill weight mud integrated in a single trip combination with all displacement or cleanout tools in the hole. The test duration is typically 30 minutes to 1 hour and the underbalance fluid is usually reversed out prior to beginning the displacement. If applicable, tie-back areas can also be tested in conjunction with the liner top and shoe. Often the liner top and PBR extension will be cleaned and addressed in the same run as well. It is important to ensure no float valve is installed in the string and various-length spaceout pups are sent to location. The backside should remain open and full during the test sequence and should be monitored closely. If it is required to use a side entry sub to pump the underbalance fluid, it is recommended to install a TIW above and below the side entry sub and a block valve in-line before the valve. All valves and surface lines should be pressure-tested to the maximum anticipated surface pressure (MASP) planned for the test and/or displacement.
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