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Rationale topic
To collect the cuttings during drilling backwash sludge, the internal pipes. They capture the solid phase occurs through a dramatic reduction of fluid velocity by increasing cross-sectional area channel in which it circulates. As a result of sludge under the influence of gravitational forces is separated from the stream and deposited on the bottom of the tube.
Practice has shown that the presence of a well service water (Newtonian fluid) collected sludge is effective. However, during the transition process water in a non-Newtonian fluid, such as prolonged contact with the rocks of the clay complex, the process of settling of sludge is deteriorating.
Therefore, to improve the effect of branch cuttings of non-Newtonian fluid used sludge trap hydrocyclones operating principle. In these devices is swirl and intense destruction of the liquid structure, which contributes to the separation of solids and discarding them to the walls of the slurry flow under centrifugal force. As a result of sludge particles are pressed to her sides and under the influence of gravity settle.
Experience of using sludge trap hydrocyclones action gives reason to believe that the destruction of the structure of the liquid flow rate should be quite high (10 - 15m / s). So far, hydrocyclone principle of destruction of the structure of non-Newtonian fluids in order to improve selection ofthe sludge only used in the ejector drill, in which local backwash created by the jet pump.
The design of the proposed internal sludge pipe (Fig. 1) allows to improve the collection of cuttings during the drilling backwash created by the pump is installed on the surface.
Device works as follows. Flow from the core barrel 15 via adapter 14, the inner channel parts 12, nozzle 10, mixing chamber (section AB channel used parts 9), the holes in the connecting sleeves 7, goes to the hydrocyclone, the channel is made in the form of rectangular grooves, cut on the outside surface of the part 6 on the helix. Ditch outside the closed interior of the details 5. Next stream strikes the conical surface of the part 4, the angle which allows one to focus reflected from it into the cavity inside the sludge slurry pipes, formed by the inner surface of the housing parts 3 and the outer surface of the interconnected parts 9, 12 and 5. To improve the collection of sludge in the cavity of the inner tube with slurry jet device creates a negative pressure for sucking in her rich slurry liquid.
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| Fig. 1 Internal hydrocyclone slurry pipe |
(Animation: volume - 50.1 kb, the size - 154 x 879, consists of 4 frames, the delay between shots - 20 ms delay between the last and first frames - 150 ms, the number of cycles of repetition - 40) |
Fig. 1.1 Аnimation hydrocyclone slurry pipe
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