SU929830A1 - Apparatus for testing producing formations - Google Patents

Description

The invention relates to drilling and can be used in hydrogeology and geology for testing aquifers when drilling by back suction washing with an airlift. BACKGROUND OF THE INVENTION Known devices for sampling formation fluid are included in a drill string assembly during a drilling process cycle. Such devices are mounted above the bit of the drill string and include a packer body, a sampler that is dumped into the drill string, and a series of channels, valves, and grooves. Channels, valves and grooves serve to connect the internal volume of the sampler with the sub-packer space, i.e. for sampling formation fluid 1. It is also known a device for testing formations, in which I have a spring loaded valve and valve and spool, which serve to control the operation of the packer 2. To test the formations, stop drilling, lower the sampler into the drill string. This actuates the valve and the channel connecting the sampler chamber. with annulus where the pressure is equal to the hydrostatic pressure of the fluid filling the well bore. As the pressure inside the drill pipe increases, the slide valve moves down, pulling the spool along. In this case, the liquid enters the packer cuff and the packing process takes place. With a further increase in pressure in the pipes, fluid from the reservoir through the channels of the bit enters the sampler. With a decrease in pressure in the pipes, the channels overlap, in compartment, in the sampling probe of the formation fluid. Channels are opened through which the podpakernogo space with the internal cavity of the drill pipe. The slide valve and slide valve provide a message to the internal cavity of the packer with the sub-valve. keru space. In this way, the pressure is leveled in all the sampling zones. The closest to the invention to the technical essence is a device for testing productive formations, comprising a housing mounted on a drill string with a longitudinal channel and a sub in the lower part for connecting with a bit, attached to the copra an inflatable packer and a packer control system including a spring-loaded valve installed in the channel for removal of the working agent, and the outlet channel with the exhaust valve, made in the form of a sleeve 3.

The tool is equipped with a sampler being moved inside the drill string. The intake and exhaust valves are combined into one control valve located on the body. The valve responds to the pressure in the wellbore and to the pressure in the pipe string. In doing so, the control valve moves in the same direction with increasing pressure drop between the drill string above the sampler installed in the housing and the wellbore above the packer. The adjustment valve is moved to connect the packer. with the drill string and the subsequent decompression packer. The same valve moves in the opposite direction in the event of a decrease in the pressure drop between the drill string above the sampler installed in the housing and the wellbore above the decompressed packer to connect the packer to the wellbore and to drive the packer

to the starting position.

one

The sampler is moved inside the drill string on the cable after stopping the drilling process. After lowering the sampler, pressure is applied to the booster column. Due to the presence of a control valve, the channels are opened to inform the drill string with the packer. With a further increase in pressure, the channels connecting the sub-packer space with the inner chamber of the sampler open. Through these channels, the reservoir fluid enters the sampler. When the pressure in the string is reduced, the control valve moves to its opposite position, detaches the sampler from the sub-packer space and connects the packer to the wellbore. The pressure levels off, the packer comes back to its original state, the sampler with a sample of the formation fluid is removed from the drill string.

The known device consists of a housing with an inflatable packer, a system for controlling the operation of the packer; those. its release and compression in the well, and the sampler. The packer control system includes a longitudinal channel with branches and chambers, a control valve and other spring-loaded valves.

In known devices, the volume of a sample of a reservoir fluid to be taken is limited by the volume of the inner chamber of the sampler. This does not exclude the possibility of getting into the sample a washing liquid and taking only washing liquid. It follows that the information content of the sample is very limited and it makes it possible to determine only. Some of the qualitative characteristics of the reservoir fluid. At the same time, it is not only the small volume of the sampler that impedes the informativity of the sample, but also the fact that, in the drilling projectile with direct flushing, the stimulation of the formation can be accomplished only by briefly applying pressure to the column. Then a sample is taken already due to the pressure difference between the formation and the sampler.

The purpose of the invention is to increase the informativity of the sample being taken during the drilling of a well with a reverse airlift wash.

This goal is achieved by installing a saddle for the rejection discharge valve on the inner surface of the longitudinal channel of the housing, and an exhaust valve is installed in the channel of the housing below its seating saddle and is made with an additional seating saddle for the waste valve whose diameter is smaller than the diameter of the exhaust pressure valve , the sub is connected to the housing by means of a spline connection with the possibility of interaction with the exhaust valve.

Figure 1 shows the device, a vertical section; .na figure 2 - section aa in figure 1; on fig.Z - section bb in figure 1; in Fig.4 m section bb In Fig.1.

The device includes a clutch 1, having a hex in the upper part | Annika with beveled tops, to which the casing 2 is welded. The casing and the clutch form segmental channels 3. On the cylindrical part of the coupling there is an exhaust valve 4, preloaded with spring 5, located in the annular groove 6 of the clutch 1. There are holes in the clutch 7. Between the cylindrical part of the coupling 1 and the casing 2 there is a gap forming the channel 8. At the end there are grooves 9. Coupling 1 is attached to the housing 10.

Between the shoulder of the casing 2 and the housing 10 there is a gap 11. The upper part of the rubber packer 12 is clamped by the cylinder 13 welded to the housing 10. In the cylinder 13 there is an annular groove 14 and the holes 15, the lower part of the packer is clamped by the cylinder 16 welded to the housing 10 and connected to the fixture to return to the initial position of the exhaust valve 17. The device consists of a ring 18, mounted on the clutch 19. K

the ring 18 is welded to the casing 20. In the lower part, the sub 21 is welded to the casing 20. The coupling 19 is screwed to the casing 10 in the thread. In the casing 10 there are outlets 22. The valve seat 17 is sealed to seal the casing 10. All maniple With valves and sampling, a longitudinal bore 25 is made in the housing 10. There is a rejection ball valve 26 and a recess valve 27. In the upper part of the valve 17 there is a seat 28 under the valve 27.

The reservoir testing device operates as follows.

During the normal drilling cycle, the method of backwashing air from the air ducts of the drill pipe passes through the channels 3, the valve 4 is released and through the holes 7 enters the channel 25, where the liquid column is aerated.

After opening the aquifer under investigation, the drilling is suspended and the device is raised above the bottom. A channel valve 26 made of a material whose specific weight is not much higher than the specific weight of the flushing agent 30 is lowered into the channel 25. The valve 26 sits on the saddle 24. Thereafter, on the output line, the drill string switches over to the valve. Air through the channels of the drill string by the compressor used during drilling pumps air into the channels 3. As the pressure in channel 25 iji channel 3 is equalized, valve 4 moves to the annular groove 6 and opens the airway duct B , grooves 9, the gap 11, grooves 14, the hole 15, falls into the space between the housing 10 and the packer 12, which begins to inflate-dg s. Inflating the packer 12 presses against the walls of the well and isolates the wellbore portion from the rest of the space. After equalizing the pressure in the packer 12, channel 3 and channel 25, which is fixed by a compressor pressure gauge or a safety valve on the compressor receiver, the valve 4 returns with a spring 5. After that the valve opens at the outlet and the liquid is bounced 55 from the bottomhole zone through the holes in the bit and the channel 25, since the upper part of the well is blocked, water comes from the aquifer. After the liquid is pumped out, which is equal to the volume of the isolated bottomhole zone, samples are taken and other parameters of the aquifer are recorded. Packer quality is recorded at the wellhead. If about 65

a drop in the level occurs during trial pumping, which means the packer is not properly manufactured. For a quality packer, the packer is moved to a depth and all manipulations are repeated. With quality poker, there is no drop in level when pumping. For a more precise fixation, special indicators (dyes, etc.) are introduced into the well (above the packer zone).

During pumping, the waste valve 26 is carried by a flow of upstream fluid to the surface. At the end of pumping, a smaller rejection valve 27 is lowered into the column, which sits on valve seat 28. The discharge valve closes, pressure is applied to the column and valve 17 is moved, opening hole 22. Simultaneously, the sub 21 is moved with the case 20 and ring 18, if they have not previously moved under the weight of the bit screwed on nickel 21. After that, the valve is opened on the discharge, the pressure in the column drops, the pressure in the packer 12 is relieved through the holes 22, moves away from the walls and returns to its original position in seconds even elastic properties are carved.

After relieving pressure, an air-lift flush is created. The suction flush valve 27 rises to the surface. The discharge valve is discharged to the bottom of the well. Under the weight of the projectile, the sub 21 returns to its original position and thereby returns the valve 17.

If it is necessary to repeat the testing or the need to test the newly opened aquifer, all operations are repeated from the beginning.

This design of the testing device allows reducing the time from the moment of opening to the time of testing to a few minutes. Airlift pumping allows deeper reservoir excitation, which makes it more informative and increases the volume of samples obtained. In addition, the device allows for the study of thin aquifers that are not studied by conventional means due to economic inexpediency or lack of technical means. Installing the device on a drilling rig allows you not to increase the number of tripping operations compared to drilling without testing. The use of plastotestors and testers, launched on f drill pipes, but not inserted into the shell when drilling wells, increases the number of trips by the number of tests

or tests, which significantly affects drilling performance.

Claims (3)

1. USSR author's certificate No. 306745, cl. E 21 V 49/00, 1966. h 2. USSR author's certificate No. 317783, cl. E 21 V 49/00, 1968. 3. US patent 2,850,240, cl. 166-162, pub. 1972 (prototype)