Study and Application of Pressure Control Valve in Dual-Packer Multistage Fracturing System
The dual-packer multistage fracturing system is the dominant horizontal well fracturing technique in the Daqing oil field, which adopts the dual packers to stimulate the targeted formations one by one. For several intervals, treatment can be done in one trip; reverse sand flushing and pulling the tubing upward fulfills the multiple stage fracturing operations. However, long time fluid discharge is needed before pulling the tubing upward in order to reduce the overflow of the tubing, which leads to the high-operation cost and the low job efficiency . Tubing plug is often used to seal the oil pipe for pulling the tubing upward without fluid discharge. But the operation of running tubing plug is complicated and increases costs. Especially in horizontal well, it is difficult to run plug to working depth and set it. A new pressure control valve is developed and can achieve switching by controlling the pressure difference between tubing and casing, which offers a hydraulic control method to seal the oil pipe and makes the anti-blowout operation simple. Field runs have confirmed that this new pressure control valve is viable option to reduce the overflow of the tubing and improve operation efficiency in the dual-packer multistage fracturing operation.
KeywordsPressure control valve Dual-packer Fracturing Anti-blowout Direct flushing Reverse flushing
- 3.Liang Y, Yue Q, Zhang Z (2009) Horizontal well sectional frac technique with dual-retrievable packers in Daqing oilfield. In: SPE 119071, 2009 SPE Middle East oil & gas showGoogle Scholar
- 4.Lin L, Feng S, Chong J (2012) The application of horizontal well coiled tubing frac technique in the Daqing oilfield. In: SPE 156446, SPE IADC/SPE Asia Pacific drilling technology conference and exhibition, 2012Google Scholar