SU1654563A1 - Circulation fill-in arrangement for testing holes - Google Patents

Abstract

The invention relates to the mining industry and is intended for testing oil and gas wells. The purpose of the invention is to increase reliability in operation due to the possibility of providing a given depression to the formation without destroying the rocks forming it. In case 1 above the differential shut-off sleeve 2, a check valve 3 is installed with an axial central channel. The latter is coaxial with the axial central channel of the sleeve 2, which is made with radial stepped channels in the upper part to communicate the radial channels of the housing 1 with its cavity above the valve 3 when the device is lowered up to a given level In the lower part of the housing 1 is placed a hydraulic cylinder 5 with radial throttling channels. The latter inform the chamber of the hydraulic cylinder 5 under and above the piston b, respectively, with the cavity of the housing 1 under the sleeve 2 and the space behind it. The valve 3 is installed with the possibility of blocking the radial channels of the sleeve 2 when it is moved to the uppermost position. To eliminate the effect of short pressure impulses to the actuator that occur in the pipes when the tool is lowered, the input and output channels of the hydraulic cylinder 5 are throttled to cut off the positive component of the pressure pulses. .4 sludge from S ate N SP about CJ

Description

The invention relates to the mining industry, namely to equipment for testing oil and gas wells,

The aim of the invention is to increase the reliability of the device for estimating the possibility of providing a given depression to the reservoir without destroying its rocks.

Fig. 1 shows the device during the descent of a predetermined level of the fluid being poured into the pipes; Fig. 2 shows the same in the closed position after reaching the planned liquid level in the pipes; on fig.Z - the same. the differential piston is at the second level of contact with the locking sleeve; Fig. 4 is the same, the closure sleeve is in its extreme upper position.

The device consists of a hollow cylindrical body 1 with axial and radial channels A, a differential locking sleeve 2 with radial stepped channels B and an axial channel B, a check valve 3 with an axial central channel; the overlapping radial channels B of the retainer 4. integrated in the lower part of the locking sleeve 2, the hydraulic cylinder 5 with throttling radial input channel G and the output channel D, as well as a differential piston 6 placed in its chamber 6. The axial central channel in the check valve is located coaxially with the axial channel of the sleeve 2 .

In the layout of the test equipment, the device is installed above the porn-rotary valve through 1-2 candles and lowered into the well as shown in FIG.

The device works as follows.

When the tool is lowered into the well, the closure sleeve 2 is in the lower extreme position — its radial channels B are aligned with the radial channels A of housing 1 and closed by a check valve 3, the differential piston b is in the lowest position relative to the hydraulic cylinder 5, and the differential piston rod is in contact with the bottom surface of the undercut of the locking sleeve 2 (first level). Latch 4 is held compressed by the differential piston rod 6.

After attaching the section (candle) of the drilling tool and its subsequent lowering, the sublevel of the fluid, the check valve 3, the flow of fluid coming from the piping through the combined radial channels A and B.

up and the liquid enters the pipes before they are completely filled

When the specified fluid level is reached, the descent of the instrument is stopped, in

In connection with this, the flow of fluid from the annulus into the pipes disappears, the check valve 3 sits in the upper recess and closes the radial channels B of the shut-off sleeve 2. The leading pipe (square) is attached to the sleeve of the last pipe and the pump creates excessive pressure in the pipes the action of which the differential piston 6 moves to the extreme upper position and. I will influence my

5 by a rod to the locking sleeve 2, forcing it to move upwards by an amount equal to the stroke of the differential piston 6 (Fig. 2). In this intermediate position, the locking sleeve 2 is fixed

0 in any known manner so that its movement to the lower position becomes impossible, but does not preclude its movement upwards. As a result of the movement of the locking sleeve 2 in the intermediate

5, the position of its radial channels B changes its position relative to the radial channels A of housing 1 and is separated from one another by sealing rings. In this position, the flow of fluid from

The hole 0 in the pipes becomes impossible and the further descent of the tool to the bottom occurs with the level of fluid reached.

With this, the pressure of the fluid in the annular space increases, and the pressure in the pipes remains constant even at the moment when the force acting on the annular surface of the piston 6 from the fluid pressure in the annular space, coming through channel D, exceeds the force from the pressure of the liquid in the pipes , acting on the lower end surface of the piston 6. It will move to the lowest position (Fig. 3). Differential rod

The 5 piston 6 will release the retainer 4, and it will move to the extreme left position under the action of the spring, which will limit the free travel of the differential piston 6 upwards. Thus, the second level of contact of the locking sleeve 2 with the end surface of the rod of the differential piston 6 is carried out.

After completion of work when lifting the tool to the level of liquid in the pipes

5 again it becomes necessary to connect the annulus with the tubular space. For this purpose, the lead pipe is attached to the last pipe coupling, an overpressure is created in the pipes by the pump. Differential piston 6 by force

from this pressure will move upwards and with its stem in contact with latch 4, as shown in Fig. 4, will force the locking sleeve 2 to the extreme upper position, where it will lock in any known manner. In this position, the bottom end surface of the locking sleeve 2 The radial openings A of the housing 1 will be higher and the liquid from the pipes may freely flow into the e-tube space.

In the process of lowering the drilling tool during its landing on the rotor, significant braking accelerations occur, causing the formation of short-term (not more than 5 s) pressure pulses that reach significant values (60 atm and more), which, acting on the differential piston 6, can move it and the stop valve sleeve 2 to the extreme upper position and in order to cause premature failure of the well survey program. To eliminate the effect on the actuator of the device of short-term pressure pulses that occur in the pipes during the descent of the tool, the inlet channel D and the outlet channel D of the hydraulic cylinder are throttled. cutting off the positive component of pressure pulses. This is explained by the fact that pressure drops here and the larger, the smaller the cross-sectional area of the channels and the higher the flow rate of fluid through them.

To determine the pressure drop (L P), the stroke length of the differential piston L is chosen to be 100 mm, and its largest diameter D is 50 mm (Fig. 2). Hence the volume of fluid (V) entering the differential piston is 200 cm3. Since the duration of the pressure pulses (t) is 5 seconds, the flow rate of the fluid (Q) over this period of time can be found from the expression

Q Y 40 cm3 / s (4.105m3 / s).

Then find the flow rate of the fluid flowing through the throttling channel, assuming that the channel length is 100 mm and its diameter (d) is 1 mm:

-

V

4 XQ

50.93 m / s

P Xd2 Determine the number of Reo V Xd

ReD

hw

 50910 5,091-Ю4

where Ur.zh. - the kinematic viscosity of the working fluid is 0.01 St (cm2 / s)

Since the found value of R PM lgzht in the region of 4000 RPr 1000 to determine the coefficient of hydraulic m of resistance A use the extrusion obtained by Alshgul

A -0.1 X (

1 46 X k- ,.

i. 10 ° V +

ten

15

20

25

thirty

35

40

45

50

55

where kEk - the coefficient of roughness

For round pipes made of art. Cack lies in the area (1-2) 10 m. From here I - 0.0392 Finding mR from the expression Darcy Wei

sbah

2

 X I - 6100770 Pa (61.01 atm). 2. X O

Despite the fact that the pressure drop at the inlet and outlet is not taken into account, the value obtained from the channel, nevertheless, completely satisfies the yr.no views that can be encountered during the descent of the circulating-casting device its actuator motive (differential piston). In the few cases when the excess length of the LP in the inlet is greater than 60 atm, this overpressure is assigned to the flow channel of the hydraulic cylinder.

Foor vl p invention

Circulating-casting device for testing wells, containing a cylindrical hollow body with axial and radial channels, in which 0 | a differential closure bushing with a main channel and a retainer; a hydraulic cylinder with a chamber in which a differential piston is installed, characterized in that, in order to increase the reliability of the device due to the possibility of providing a given depression to the formation without destroying its component rocks, it is equipped with a check valve, mounted in a housing above the differential shut-off sleeve and made with a central axial channel, arranged coaxially with the axial channel of a stop sleeve which is made with stepped The upper channels for communicating the radial channels of the housing with its cavity above the non-return valve when the device is lowered to a predetermined level, the hydraulic cylinder is located in the lower part of the housing and is made with radial throttling channels for communicating the cylinder of the hydraulic cylinder below and above the piston respectively with the water housing cavity and the space behind it, and the check valve is installed with the possibility

block stepped radial Kan-when it is moved to the topmost floors of the differential closure sleeve, the position.

Claims (1)

A circulation and filling device for testing wells, containing a cylindrical hollow body with axial and radial channels. in which it is installed! differential locking sleeve with a main channel and a retainer, a hydraulic cylinder with a chamber. in which a differential piston is installed, which differs in that. in order to increase the reliability of the device due to the possibility of providing a given depression on the formation without destroying the rocks composing it, it is equipped with a check valve installed in the housing above the differential locking sleeve and made with a central axial channel located coaxially to the axial channel of the locking sleeve, which is made with step radial channels in the upper part for communicating the radial channels of the housing with its cavity above the check valve when the device is lowered to a predetermined level; dr is located in the lower part of the housing and is made with radial throttling channels for communicating the chamber of the hydraulic cylinder under and above the piston with the iodine cavity, the locking sleeve and the space behind it, and the check valve is installed with the possibility of overlapping stepped radial channels of the differential locking sleeve when moving to the extreme top position.