RU92462U1 - IMPELLER - Google Patents

Abstract

A vane wheel containing a shaft and with blades fixed on it, made in the form of screw segments, characterized in that the pitch of the helical line of the blades is selected from the following mathematical expression:! ! where P1 is the pitch of the helix of the blades, mm; ! P2 - screw pitch of the screw conveyor, mm.

Description

The utility model relates to the field of engineering and can be used in the oil industry for the operation of well installations with a rotating column of pump rods.

Impellers are known that rotate in a centrifugal pump housing and contain a drive and a driven disc with vanes located between them (Ivanovsky V.N., Darishev V.I., Sabirov A.A., Kashtanov BC, Beijing S.S. Borehole pumping units for oil production. - M: State Unitary Enterprise. Oil and Gas Publishing House of the Gubkin Russian State University of Oil and Gas, 2002. - pp. 14-18)

The disadvantage of these impellers is unsuitability for operation in the well as an element of a rotating rod string due to the inadequate design of the blades.

A screw pump is known, consisting of a housing with an outlet pipe, a multi-auger screw installed in its cylindrical cavity, the single-stroke part of which is covered by a blade feeder with a part of the movable housing, having different speeds and directions of rotation with a screw and coaxially placed shafts (RF patent No. 2177087, 7 F04D 7/00, published on December 20, 2001). The specified auger in technical essence is closer to the proposed impeller, and it can be taken as a prototype.

The disadvantage of the screw compared with the blade in the form of segments of the screw is the high cost in the manufacture, it is technologically difficult to manufacture.

The technical task of the claimed utility model is to increase the rate of fluid rise near the walls of tubing, prevent sand from settling over the pump, increase the pressure of the fluid, increase the well overhaul period.

The technical task is solved by the described impeller wheel, containing a shaft and with blades fixed on it, made in the form of screw segments.

New is that the pitch of the helix of the blades is selected from the following mathematical expression:

Where

P ₁ - pitch helix of the blades, mm;

P ₂ - pitch helix conveyor screw, mm.

The proposed utility model is illustrated by drawings, where:

- figure 1 shows the impeller, left view;

- figure 2 - impeller, front view;

- figure 3 - impeller, location in the working position;

- figure 4 is a well equipped with a screw pump with a surface drive.

The impeller wheel (Fig. 1) contains a shaft 1 with threads 2 and 3 connecting at the ends, blades 4 made in the form of screw segments connected to the shaft 1 inseparably, for example, welded, riveted, welded joints, thermo-pressing, filling, soldering, forming etc. The column of pump rods 5 (Fig. 3) is connected to the shaft 1 by threads 2 and 3. The blade 4 is part of a special screw - a screw conveyor (not shown in the figures), and the pitch P _{1 of the} screw line of the blade 4 is less than the pitch P _{2 of the} screw screw conveyor lines The linear dimensions of the blades 4 are sides a, b, c and e (figure 2). The diameters of the cylindrical surfaces (figure 2), respectively, d ₁ and d ₂ . Diameter d ₁ = d ₂ + 2a. The sides b and e of the blade 4 are in contact with the contour forming surface of the shaft 1 of diameter d ₂ . The blade 4 can be with a square, rectangular, trapezoidal, triangular, and other profile. Between the impeller (Fig. 3) and the tubing 6 there is an annular gap 7 to the blades 4 and an annular gap 8 after the blades 4. The blade 4 can be made of either metallic or non-metallic material. In the case of the manufacture of the blades 4 metal, the outer surface of the blades 4 and the shaft 1, in order to harden, can be processed thermally or by high frequency currents. The arrangement (number) of impeller wheels in the string of pump rods 5 and the number of blades 4 on the shaft 1 depends on the nature of the fluid being pumped and the operating conditions. Also, depending on the operating conditions, the angles α and β can be selected in a wide range. The sides b and e of the blade 4 may not necessarily be perpendicular to the axis of the shaft 1. The slopes of the blade 4 are necessary for more efficient operation of the rod blade.

A well equipped with a screw pump installation (Fig. 4) comprises a reservoir 9, a casing 10 with perforations 11, a screw rod pump 12 with a string of pump rods 5, tubing 6, a drive head 13 with an electric motor 14, and wellhead 15 and a fluid transfer line 16. The drive head 13 is mounted on the wellhead 15. The drive head 13 is connected to a polished rod 17, which is connected to the column of pump rods 5.

The impeller operates as follows.

When the electric motor 14 (Fig. 4) of the drive head 13 is turned on, a polished rod 17 and a column of pump rods 5 rotate. The fluid of the formation 9 rises through the perforation holes 11 to the wellhead with a screw rod pump 12 through the tubing 6 and then enters the fluid transfer line 16.

When the column of pump rods 5 rotates (Fig. 3), the liquid rises along the annular gap 7 in the axial direction along the impeller and then moves from the vane 4 in the radially axial direction (from the center to the periphery under the action of centrifugal forces) into the annular gap 8. The greatest the liquid reaches the angular velocity at the outlet of the blade 4. In the annular gap 8, a turbulence of the liquid stream is created, at which its speed increases at the walls of the tubing 6. Due to the uniform constant rotation of the blade shaft ca movement of pumped liquid will also be uniform (decrease vibrations in the well), but due to the fluid jet vortex prevents settling of solids on the screw rod pump 12. Under the action of centrifugal force also occurs on the separation of the liquid fraction. Water and mechanical impurities will be located near the inner walls of the tubing 6, oil will occupy an intermediate position at the blades 4, and the gas from the mixture, as the least dense, will be located near the shaft 1. The impeller will prevent the formation of oil-water emulsion in the tubing pipes 6 in the process of lifting the liquid to the surface. All this will reduce the cost of operating equipment and the preparation of commercial oil.

Thanks to this design of the impeller, the speed, pressure and pressure of the fluid increase. It is especially effective when moving a viscous fluid, as well as to prevent settling of mechanical impurities over the pump, which will increase the well overhaul period, reduce wear of the “rotor-stator” friction pair, jam the rotor in the stator and breakage of the pump rod string.

Claims (1)

A blade wheel containing a shaft and with blades fixed on it, made in the form of screw segments, characterized in that the pitch of the helical line of the blades is selected from the following mathematical expression:

where P ₁ is the pitch of the helix of the blades, mm; P ₂ - pitch helix conveyor screw, mm.