Water Circulation Test on Adjustable Throttle Nozzle Based Multi-Specification Inside Cutters
In order to improve the efficiency of cutter inside the tubing and avoid adverse phenomena such as insufficient extension of the cutter,rapid wear-out failure of the blade and uncontrollable nozzle flow during tubing cutting,a series of adjustable throttle nozzle based interchangeable multi-specification in tubing cutters were devel-oped.A dedicated testing platform was designed to verify the reliability of the inside cutters,and the key structure design and testing sequence were introduced.The test was composed of initial cutting,normal cutting,cyclic start-stop cutting and wear cutting tests.The results show that when the main structure and initial outer diameter re-main unchanged,the series of cutters can adapt to cutting different specifications of tubing,and the adjustable throttle nozzle can meet the pressure of the field pump unit and ensure the cutters to keep a reasonable rotation speed.The cutters can cut off ø73.0 mm tubing within 163 seconds,and the duration for multiple start-stop cutting of ø 73.0 mm tubing is 179 seconds.After severe wear,the cutters can cut off ø89.0 mm tubing within 426 sec-onds,and the cutters have a service life of up to 4 times.When cutting,the cutters need to slowly cut in;when approaching the tubing wall,the cutters need to stay for about 23 seconds to reach a stable state,so as to prevent pump blocking phenomenon from occurring.The test results show that the extension range of the cutters can be ad-justed to adapt to different outer diameters of tubing,and the blades can complete cutting operations for many times under different nozzle flow rates.The proposed cutters provide technical support for field workover operations.
万方数据
维普
