| Oil testing data are acquired by three phases: testing static shut in pressure, pumping testing and shut in pressure restoring. These techniques can be finished only on surface shut in by normal tubing, the advantage is that continuing the data acquiring can be done, but will induce the effect of wellbore storage. It's more prominent in"three lowers"reservoirs. The testing period in shut in pressure restoring phase is as long as 3—6 months, making the testing period longer and cost higher, pulling up pumping tube after pumping finished, measuring the pressure by lowering formation testing tools, downhole shut in can be finished, shortening the time of pressure measuring, but pressure data acquiring is not continuing, data interpretation is not very accurate, you must repeat the jobs, increase the working intention and producing cost.As above, we have studied oil testing downhole open and shut in pressure monitoring technique technology for 2 years, completed the all works of the project, all the items accorded with the designed demand, realized the pumping testing by one trip and downhole open and shut in ,resolved the problems of cable core easily cut by cable binding downhole and measuring the outer and inside pressure simultaneously, taking and monitoring the pressure data at any moment, keep sealing the downhole and wellhead cable. We succeeded in two testing wells: Chuan 4 and Fang 114-2. The technique's studying and application makes them ensured, acquiring the data of testing well continuously, reducing the effect of wellbore storage, simplifying the procedure, shortening the oil testing period, accurating the oil testing data acquiring and interpretation.The technique used downhole open and shut valves, respectively testing pump, packer, pressure read-out carrier, connecting slotted hoop, cable sealing tools and so on. The technique of open and shut in downhole oil testing can be realized through the string combined by these tools.The principle of oil testing by formation downhole open and shut in and pressure monitoring technique technology is to pack by packer on the upper reservoir, bring downhole open and shut valves or relative tools on the lower part of testing string, open and shut well downhole through pumping stem or tubing designed three string structures to different testing situations. Not only oil testing but also downhole open and shut in and pressure monitoring, reducing effect of wellbore storage, shortening the period of pressure restroring, improving oil testing effect. |
