RU155902U1 - LOW DRILL POSITION LAYOUT WITH ELECTRIC SUBMERSIBLE PUMP - Google Patents

Abstract

The layout of the bottom of the drill string with an electric submersible pump, consisting of drill pipe, a downhole motor, a support-centering element, weighted drill pipes and drill pipes with a conductor, sequentially placed on the drill string, characterized in that the drill pipes are above the zones of catastrophic absorption of drilling fluid, but below the steady-state level in the well, they are equipped with an electric submersible pump connected to the current lead, the electric submersible pump circulating the flushing of the liquid in the well without departing from the surface, the drill pipe opposite the electrical submersible pump is equipped with a bypass channel.

Description

The proposal relates to drilling equipment and can be used to compose the layout of the bottom of the drill string when drilling wells in areas of catastrophic fluid absorption.

Known layout of the bottom of the drill string (patent for utility model RU No. 93868, IPC ЕВВ 7/06, published May 10, 2010) comprising a bit, a downhole hydraulic motor, drill pipes, and the device is additionally equipped with a vibrator located in the bit body, and a shock absorber installed between the vibrator and the hydraulic downhole motor.

The disadvantages of this layout are:

- firstly, the complexity of the design, due to the large number of nodes and parts (vibrator located in the body of the bit, shock absorber);

- secondly, low work efficiency, as when drilling a well under a conductor in areas with catastrophic absorption of flushing fluid, the layout does not reduce the absorption of flushing fluid;

- thirdly, the long duration of work is associated with a low penetration rate when drilling a well under the conductor in areas with catastrophic absorption of flushing fluid, since the layout does not allow to reduce the flow (reduce costs) of flushing fluid;

- fourthly, there is a high probability of sticking the bottom of the drill pipe string due to flushing fluid “leaving” and accumulation of drill cuttings at the bottom when drilling a hole under the conductor in areas with catastrophic absorption of drilling fluid.

Also known is the layout of the bottom of the drill string (utility model patent RU No. 58151, IPC ЕВВ 7/06, published November 10, 2006) consisting of a bit, a downhole hydraulic motor, a support-centering element mounted between the bit and a hydraulic downhole motor, - a centering element mounted on a downhole hydraulic motor, a drill pipe and an eccentric support-centering element mounted between the threaded joints of the drill pipe string.

The disadvantages of this layout are:

- firstly, low operating efficiency, as when drilling a well under a conductor in areas with catastrophic absorption of flushing fluid, the layout does not reduce the absorption of flushing fluid;

- secondly, the long duration of the operation is associated with a low penetration rate when drilling a well under the conductor in areas with catastrophic absorption of flushing fluid, since the layout does not allow to reduce the flow rate (reduce costs) of flushing fluid;

- thirdly, a high probability of sticking to the bottom of the drill pipe string due to flushing fluid leaving and drill cuttings accumulating in the bottom when drilling a hole under the conductor in areas with catastrophic absorption of flushing fluid.

The closest in technical essence and the achieved result is the layout of the bottom of the drill string (patent RU No. 2236538, IPC ЕВВ 7/06, published September 20, 2004), consisting of drill bits, a downhole motor, a support-centering element sequentially placed on the drill string , weighted drill pipes and drill pipes with a current lead, while the layout is equipped with a motor eccentric working pair, consisting of a housing in which a screw element is mounted, rigidly connected to the drill pipe string, and on both at their ends, sub-seals are installed with stuffing box seals, and ribs mounted at an angle to the layout axis are placed on the outer surface of the body and sub.

The disadvantages of this layout are:

- firstly, low work efficiency, as when drilling a well under a conductor in areas with catastrophic absorption, the layout does not allow to reduce the absorption of flushing fluid;

- secondly, a high probability of sticking the bottom of the drill string due to “leaving” the drilling fluid and accumulation of drill cuttings at the bottom when drilling a hole under the conductor in areas with catastrophic absorption of drilling fluid;

- thirdly, the long duration of work is associated with a low penetration rate when drilling a well under a conductor in areas with catastrophic absorption, since the layout does not allow to reduce the flow rate (reduce costs) of the flushing fluid.

The technical task of the proposal is to increase the efficiency of the assembly, reduce the likelihood of sticking the bottom of the drill string, as well as reduce the duration of the work when using the layout when drilling a conductor hole in areas with catastrophic absorption of drilling fluid.

The stated technical problem is solved by arranging the bottom of the drill string with an electric submersible pump, consisting of chisel pipes, a downhole motor, a support-centering element, weighted drill pipes and drill pipes with a conductor, sequentially placed on the drill string.

New is that the drill pipe above the catastrophic absorption zones of the flushing fluid, but below the established level in the well are equipped with an electric submersible pump connected to the conductors, and the electric submersible pump circulates the flushing fluid in the well without reaching the surface, while the drill pipes opposite the electric submersible pumps are equipped with a bypass.

Well drilling under the conductor in areas of catastrophic absorption of flushing fluid is a significant problem in well construction. When passing through such zones, a significant amount of material and financial resources and time is spent on the reclamation, cementing and drilling. This is due to the presence of natural and formed during drilling caverns of significant size in areas of catastrophic absorption, where the flushing fluid goes.

The figure schematically depicts the proposed layout of the bottom of the drill string with an electric submersible pump.

The layout of the bottom of the drill string with an electric submersible pump consists of drill bits 1 sequentially placed on the drill string, a downhole motor 2, a support-centering element 3, weighted drill pipes 4 and drill pipes 5 with a current lead (not shown in the figure).

Drill pipes 5 above the zones 6 of the catastrophic absorption of the flushing fluid, but below the steady-state level 7 in the well 8 are equipped with an electric submersible pump 9 connected to the current lead. An electric submersible pump 9 circulates the flushing fluid in the borehole 8 without reaching the surface.

Drill pipes 5 opposite the electric submersible pump 9 are equipped with a bypass channel 10.

The layout of the bottom of the drill string with an electric submersible pump works as follows.

When drilling a borehole 8 under a conductor in zones 6 of catastrophic absorption of drilling fluid, a bottom hole assembly is assembled at the wellhead 8 as shown in the figure. The layout of the bottom of the drill string is lowered into the well 8 so that after it is lowered into the drilling interval, the electric submersible pump 9 is at a depth of h = 15-20 m below the established level 7 in the well 8.

In the process of lowering the drill pipe string into the well 8, it is flushed through the layout of the bottom of the drill string. For this, from the wellhead 8, flushing fluid is supplied to the drill pipe string. Flushing fluid through drill pipes 5 (above the electric submersible pump 9), bypassing the electric submersible pump 9 through the bypass channel 10 and drill pipes 5 (below the electric submersible pump 9), and then through the weighted drill pipes 4, supporting centering element 3, the downhole motor 2 and the bit 1 enters the well 8.

In the process of drilling (deepening) the well 8 under the conductor in the zones 6 of the catastrophic absorption of the well 8, the supply of flushing fluid from the wellhead into the drill pipe string 5 is stopped.

Start up the electric submersible pump 9, powered through a conductor mounted on drill pipes 5.

The electric submersible pump 9 selects the downhole fluid (flushing fluid) from the well 8 below the steady-state level 7 and then through the drill pipes 5 (below the electric submersible pump 9) through the weighted drill pipes 4, the support-centering element 3, the downhole motor 2 and the bit 1 feeds flushing fluid to the bottom 11 of the well 8 to clean the bottom 11 of the cuttings.

Thus, when the well is deepened beneath the conductor in zones 6 of catastrophic absorption of flushing fluid, flushing fluid is circulated in well 8 through an electric submersible pump 9, both without flushing fluid coming to the surface and without flushing fluid being supplied to the drill pipe string, while rock in the form of deposited sludge is distributed in caverns of 12 zones 6 of catastrophic absorption.

As a result, significant savings on flushing fluid are achieved and work efficiency is increased since when drilling a conductor well in zones 6 with catastrophic absorption of flushing fluid, the layout allows distributing drill cuttings in the form of deposited sludge in caverns 12 of catastrophic absorption zones 6, and thereby reduce absorption flushing fluid in the well.

Significantly reduces the likelihood of a seizure of the bottom of the drill string, due to a decrease in “drift” of drilling fluid and accumulation of drill cuttings not in the bottom 11 of well 8, but in its distribution in caverns 12 of zone 6 of catastrophic absorption of drilling fluid.

When applying the proposed layout of the bottom of the drill string, the duration of the work is reduced due to the increase in the rate of penetration when drilling a conductor in zones 6 with catastrophic absorption, since the layout allows to reduce the flow of flushing fluid due to the lack of supply of flushing fluid to the drill string when drilling under a conductor in zones 6 with catastrophic absorption and circulation of flushing fluid in the well through an electric submersible pump 9 without the output of flushing fluid and on the surface.

The proposed layout of the bottom of the drill string with an electric submersible pump allows to increase work efficiency, reduce the likelihood of sticking the bottom of the drill string, as well as reduce the duration of the work using the layout when drilling a well under the conductor in areas with catastrophic absorption of drilling fluid.

Claims (1)

The layout of the bottom of the drill string with an electric submersible pump, consisting of drill pipe, a downhole motor, a support-centering element, weighted drill pipes and drill pipes with a conductor, sequentially placed on the drill string, characterized in that the drill pipes are above the zones of catastrophic absorption of drilling fluid, but below the steady-state level in the well, they are equipped with an electric submersible pump connected to the current lead, the electric submersible pump circulating the flushing of the liquid in the well without departing from the surface, the drill pipe opposite the electrical submersible pump is equipped with a bypass channel.

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