SU604967A1 - Device for cementing sections of casing columns - Google Patents

Description

The invention relates to devices used in cementing casing columns in oil and gas wells.

A device for cementing sections of casing strings is known, consisting of a casing, a cylinder, a cam sleeve with rods 1.

However, the prior art device does not allow reverse cementing followed by flushing the overlying interval.

A device for the production of cementing operations in a certain interval of wells, consisting of a housing, bushings installed therein with the help of shear pins, a lacquer and locking elements, is known.

However, the known device also does not allow reverse cementing.

The aim of the invention is the possibility of direct and backwashing during cementing.

The goal is achieved by the fact that the device is equipped with a differential spring-loaded piston rigidly connected to the sleeve and distribution sleeves that block the flushing channels made in the housing.

FIG. 1 shows the device during direct washing; in fig. 2 is the same during backwashing and cementing;

in fig. 3 - the same, during the washing of the overlying interval; in fig. 4 is a section A-A in FIG. 2; in fig. 5 is a section BB in FIG. 2

The device consists of a housing 1, equipped with a sub 2 in the upper part, in the central hole of which a winding tube 3 is rigidly mounted. The differential piston 6 of the cylinder 7, spring-loaded piston 6 of the cylinder 6, is connected to the lower part of the pipes. the enclosure space with several radially inclined tubes 8. In the normal position, the ends of the tubes 8 are overlapped from the inside by a differential pressure 6, and from the outside - by a vertical sleeve 9 located around the housing 1. The sleeve 9 is rigidly connected to the distribution piston 6 by radial jumpers 10 extending through vertical rectangular windows And in housing 1 and windows 12 in the cylinder 7. Between the upper end of the sleeve 9 and the projecting part of the sub 2 on the housing 1

wearing a packer 13.

In the lower part of the housing 1, a sleeve 14 is rigidly fixed, to the upper part of which a cylinder 7 is rigidly attached. In the figured sleeve 14, an axial through cavity 15 is formed, which has the shape of three cylinders with diameters decreasing downwards. In the upper cylindrical bore of the sleeve 14 is installed on the shear pins 16 of the sleeve 17, overlapping radially inclined channels 18 in the sleeve 14 and the housing 1, connecting the cavity 15 with zakorpusnym space. In the middle and lower cylindrical parts of the cavity 15, a collapsible sleeve 19 with lateral holes 20 is installed, the upper annular protrusion 21 of which rests on shear-22 pins. A spring 23 is mounted on the sleeve 19, located in the middle cylindrical part of the cavity 15. In the peripheral part of the sleeve 14, several through vertical channels 24 are formed, blocked in the normal position by locking elements 25, which are rigidly connected by radial connections 26 to the lower end of the sleeve 19. In the sub 2, several vertical circumferential holes 27 arranged around the circumference are made. To control the bushings 17 and 19, locking elements 28 and 29 are provided. In the lower part of the cylinder 7, a locking ring 30 is installed that prevents the movement of the sleeve 17 up.

The device works as follows.

The casing section is attached to the lower part of the housing 1 by means of a detachable coupling and suspended to the drill or tubing pipes by the sub 2. The device together with the casing section is lowered to a predetermined depth and thereafter the well is rinsed. Then the locking element 28 is thrown into the drill pipe, which closes the bore 19 bore section. The pins 22 are cut off and the bushing 19 together with the locking elements 25 moves downward, compressing the spring 23 and opening the channels 24. With further increase in pressure, the differential piston 6 overcomes the force compressing the spring 4, moves upward, entrains the sleeve 9 and squeezes the packer 13. As a result, the tubes 8 are opened and the cementing interval is reversed, after which the necessary we go portion of the cement mixture (Fig. 2).

After the cementing is completed, the locking element 29, which, acting on the sleeve 17, cuts off the pins 16 and moves it downwards, opens the channels 18, and the pressure in the system drops, the differential piston 6 with the sleeve 9 returns to its original position, releasing the packer 13 and closing the tube 8. The sleeve 19 under the action of the spring 23 also

returns to the upper position, entraining the locking elements 25 and closing the channels 24. After this, the channels of the overlying interval of the well are flushed out through the channels 18.

After hardening of the cement mixture, the device is disconnected from the casing by rotating the drill pipe and is removed from the well.

Claims (2)

Invention Formula A device for cementing casing sections, consisting of a body with an axial flushing hole, sleeves installed therein by shear pins, a packer and locking elements, characterized in that, in order to enable the direct and reverse flushing during cementing, equipped with a differential spring-loaded piston rigidly connected to the sleeve, and distribution sleeves blocking the flushing channels made in the housing. Sources of information taken into account in the examination 1. E. Levin, M., V. V. Vaulin. The descent and suspension of the shank when attaching wells. Grozny, 1970, p. 58-105. 2. US patent No. 2925865, cl. 166-154, pub. 1960 2 -27 W P 2b pus. 2 A-A rig. V Vb one