Research and Application of Double Overflow Control Technology for Small Pump Tubing

As oilfield development enters the middle and later stages, the number of small-diameter pumping wells with a pump diameter of 57mm or less has been increasing year by year. During the pump inspection operation, it is easy for the liquid in the tubing to splash. In response to the lack of effective overflow control measures for the secondary operation of small-pump tubing, research on the double-overflow control technology for tubing was carried out. A double-overflow prevention fixed valve was developed to replace the original fixed valve of the pumping unit, and it was equipped with an internal plug. Together with the pump barrel, they formed an integrated tubing string for overflow control and pumping. During the pump installation operation, the internal plug mechanism was used to achieve the first overflow control of the tubing. During the pump inspection operation, the sliding sleeve mechanism was activated by the pressure difference to press the valve onto the valve seat, achieving the second overflow control of the tubing. The technology was verified for its feasibility through indoor and field tests. It was applied to 25 wells in the field, including 11 wells for secondary operations. There was no overflow during the tubing operations for both pump installation and inspection, and the success rate of the first and second overflow control was 100%. The research and application of the double-overflow control technology for tubing have achieved source control of various small-diameter tubing overflows, meeting the requirements for safe and environmentally friendly construction during pump installation and inspection operations. It has the process advantages of high reliability and low cost.