RU2450112C1 - Device for drilling of well and its operation - Google Patents

Abstract

FIELD: oil and gas industry.

SUBSTANCE: device for drilling of a well and its operation comprising lifting pipes, a drill-collar string, a hydraulic downhole motor and a chisel. The device is additionally equipped with a slag and metal trap, an upper centrifugal pump to supply a fluid from a wall to a well head with partial liquid intake from the first flow and the lower centrifugal pump to create a hydraulic force to operation of a hydraulic downhole motor.

EFFECT: combined processes of drilling and oil production and increased efficiency of bed opening technology and subsequent oil production.

2 cl, 1 dwg

Description

The invention relates to the process of construction and repair of wells and can be used in oil production.

A well-known drilling rig, which includes a mud pump with a discharge hose, compressor, rotor with slurry conduit, double concentrically placed drill and lead pipes, distribution swivel. The installation is equipped with a sub installed between the lead pipe and the distribution swivel, made in the form of a double drill pipe with a drain pipe and an annular partition separating the sub into the lower slurry conduit and the upper cavity connected to the inner pipe, connected to the drain pipe through a shut-off device, and an injection sleeve the mud pump is connected to the compressor and is equipped with check valves (RF patent No. 2256770, IPC EV 21/02).

However, this installation does not provide for the possibility of oil production.

There is a method of operating a well when separate pumping of oil from the upper productive formation to the surface by the upper pump installed at the maximum working height of the operating mode and water into the water-saturated plantar area or the underlying water-absorbing layer by the lower electric centrifugal pump, facing down and having a liner with a packer installed above the roof of the water-absorbing formation or in the plantar area of the formation. The ratio of the productivity of the lower and upper pumps is selected depending on the ratio of the amount of water and oil entering the well. The total performance of the pumps is selected from the conditions of gravity separation of the formation fluid in the well into oil and water and pumping water containing no oil with the lower pump. Between the upper and lower pumps at the working depth of the depression mode, an average electric centrifugal pump is installed with a capacity greater than that of the upper pump. Periodically change the operating mode of the well to the depression mode, for which the upper pump is turned off and the middle and lower pumps are turned on. Pre-perforated water-saturated plantar region of the formation or water-absorbing layer below the oil-water contact at a distance of not less than 5 m. Two groups of holes are made in the string of tubing between the pumps (RF patent No. 2382181, IPC ЕВВ 43/12).

However, this method does not provide for the possibility of using drilling technology to deepen the well.

The closest to the proposed invention in terms of technical nature and the achieved effect is a drill string, including a bit (milling-blade, type IMS), shut-off valve (ZPK), weighted drill pipes and drill pipes. Additional elements may be included in the drill string: a throttle to control the flow rate of the fluid supplied to the drill string and a check valve to prevent the drilling fluid from being drained into the well with cuttings from the drill string when lifting the latter. The rotation of the drill string is carried out by the rotor of the drilling rig (Application for invention RU 94031715/33, 08/31/1994).

The disadvantages of this device are:

- the opening of the productive horizon is carried out by drill pipes from the drilling rig;

- Depression on the reservoir is fading;

- for pumping out of the inner cavity of the drill string requires additional equipment.

In addition, this device does not allow you to go to the stage of oil production.

The objective of the invention is to combine the processes of drilling and oil production, as well as simplifying and improving the efficiency of the technology of opening the formation and subsequent oil production.

The technical result obtained by the implementation of the proposed invention is:

- simplification of drilling technology;

- maximum preservation of the reservoir properties of the reservoir by creating any depression using centrifugal pumps;

- avoidance of the secondary opening of the reservoir, i.e. there is no need for formation perforation, hydraulic fracturing, inflow;

- in the process of drilling, a gradual transition to the production of formation fluid occurs.

The specified technical result is achieved in that in a device for drilling a well and its operation, including tubing, a string of heavy drill pipes, a hydraulic downhole motor and a bit, it is new that it is additionally equipped with a sludge trap, an upper centrifugal pump for supplying fluid from wells at the mouth with a partial intake of fluid from the first stream and a lower centrifugal pump to create hydraulic force for the operation of the hydraulic downhole motor.

Upper and lower centrifugal pumps are installed at various depths.

The proposed technical solution is aimed at using conventional technical means to open the reservoir, provided that the reservoir and hydrodynamic pressures are equal to preserve the natural permeability of the reservoir, followed by oil production.

It is known that well drilling can be carried out by direct flushing, i.e. drilling fluid is injected into the face through drill pipes. The flushing fluid drives a downhole hydraulic motor, which destroys the rock with a chisel, and carries out the removal of sludge through the annulus. In this case, the tightness of the walls of the well is a prerequisite. If there is no tightness, then there are numerous ways to restore it. Also, the efficiency of the removal of sludge is significantly reduced due to the large cross-section of the annulus, where it is difficult to create a high upstream velocity that can carry out drill cuttings. Therefore, when drilling wells of large diameter, as well as during overhaul of wells, backwashing is used.

To create a reverse and direct flushing, a pumping unit located on the earth's surface is currently used.

When drilling with direct flushing, the weight of the column of flushing fluid always acts on the reservoir, which at low reservoir pressure of the reservoir leads to its penetration into the reservoir. This circumstance further complicates the challenge of inflow from the reservoir. Various operations are carried out to call the inflow: perforation, hydraulic fracturing, etc. In order to avoid the penetration of the filtrate of the washing liquid, aeration is carried out by pumping air into the solution or by improving the quality of the washing liquid.

The proposed device allows you to combine drilling and oil production in one process, which significantly saves time and resources.

Figure 1 schematically shows the proposed device.

The device for drilling a well has the following arrangement:

1 - bit,

2 - downhole hydraulic motor (GZD),

3 - weighted or steel drill pipes,

4 - sludge trap,

5 - lower centrifugal pump (ESP),

6 - upper centrifugal pump (ESP),

7 - tubing string (tubing).

Positions 1-5 of the layout perform the function of drilling, and positions 6 and 7 of the production of formation fluid (oil).

To open the reservoir and to produce the formation fluid into the well, the following arrangement may be launched, consisting of a bit 1, a hydraulic downhole motor (HLD) 2, heavy-duty or steel drill pipes 3, a metal sludge trap 4, a lower centrifugal pump 5 directed to the bottom, an upper centrifugal pump 6 directed to the mouth, tubing string 7 to the mouth, flushing equipment, as well as a treatment system and a pipe for receiving formation fluid (not shown).

Upon reaching the bottom of the well, the pumps are turned on: the lower centrifugal pump 5 creates a direct circulation through the drill pipes 3, GZD 2 and the bit 1, and the upper centrifugal pump 6 delivers fluid from the well to the wellhead through tubing 7, partially taking fluid from the first stream. Before the drilling process begins, flushing fluid is pumped out of the well to a level equal to reservoir pressure or less (the level in the annulus is monitored using sonar). Upon reaching the required level and in order to maintain it in the annulus, refilled flushing fluid is added. Thus, reverse circulation is created. Upon reaching the stable operation of the entire system, the load on the bit 1 begins.

The proposed device implements a drilling method. The well is drilled to the top of the reservoir, then equipment is lowered into it and the casing is cemented. Fountain fittings are installed, the string is pressed together with the fountain fittings, the check valve, cement cup, shoe are drilled, the cement ring is pressed and the well is flushed to a clean liquid that does not contain a solid phase. The layout must include a sludge trap 4. Next, the well is transferred to the oil production workshop. Mounted hoist of appropriate capacity.

After the descent of the indicated arrangement, ESP 5 is turned on and flushing fluid is pumped out of the well to a level equal to reservoir pressure or less (the level in the annulus is controlled with an echo sounder). Upon reaching the required level and in order to maintain it in the annulus, refilled flushing fluid is added. Thus, reverse circulation is created. Then ESP 6 is turned on and upon reaching the stable operation of the entire system, the load on the bit 1 begins.

As the well deepens, formation fluid begins to flow and there is no need to top up the flushing fluid in the annulus. Formation fluid is routed into the pipeline to receive formation fluid.

After reaching the required drilling depth, oil can be produced with an upper ESP 6. In the event of a decrease in flow rate, the layout can be lowered and the face cleaned. One ESP can also be launched to continue production. Or a liner with perforated pipes was lowered and an ESP was lowered to continue oil production.

If there is a diverter and telemetry in the layout, drilling of new trunks is possible.

This invention can be applied when drilling new wells in the absorption zone and during overhaul of wells, where it is difficult to flush propane after hydraulic fracturing or when drilling cement bridges.

Claims (2)

1. A device for drilling a well and its operation, including tubing, a drill string, a hydraulic downhole motor and a bit, characterized in that it is additionally equipped with a sludge trap, an upper centrifugal pump for supplying fluid from the well to the mouth with partial fluid intake from the first stream and the lower centrifugal pump to create hydraulic force for the operation of the hydraulic downhole motor. 2. The device according to claim 1, characterized in that the upper and lower centrifugal pumps are installed at various depths.