RU1819987C - Device for casing cementing - Google Patents

Abstract

Usage: for cementing and wells. Provides the ability to place the filter in the cementing area. SUMMARY OF THE INVENTION: The device includes a hollow body. It has a filter with cementing holes. In the housing there is a branch pipe and a cork plug. From the bottom, a shoe pipe is connected to the filter. It is made with a shoe. The nozzle is made with upper and lower sealing flanges. An annular groove is made in its upper part. It is made under the upper sealing flange. The housing is made with end upper and lower stops. O-rings are placed on them. An annular groove is made between the stops. A clamp is placed in the annular groove. Selling plug made with a tip. It has locking elements. They are made with the possibility of tight fixation of the tip in the hole of the upper flange. The upper flange is fixed by a shear element in the housing. It is fixed above the filter. The lower flange is tightly pressed against the lower annular at the body stop. The nozzle is mounted axially movable into the shoe nozzle and the upper flange fits onto the upper annular stop of the housing. This ensures that the housing retainers are placed in the annular groove of the nozzle. Cementing holes are made in the shoe of the pipe. In this case, the shoe nozzle is made in the form of telescopic sections. Each of its subsequent sections is attached to the outside. This mount is made in the form of shear pins. 1 s.p. f-ly, 4 ill. 00 y o 00 vi

Description

The invention relates to the construction of oil and gas wells and can be used for cementing casing strings, as well as for isolating washout absorption zones during well drilling.

Well cementing devices are known for improving the quality of formation isolation by selecting the filtered liquid phase of the cement slurry inside the pipe string l and 2J.

The disadvantages of these devices are the coverage of a small cementing area due to the small surface of the filter and the inertia of putting the device into operation due to the inability to quickly release the pressure.

Closest to the invention is a device including a housing, the cavity of which communicates with its bore space, a separation plug and a filter located in the lower part of the housing, a pipe with a destructible membrane, a pusher and a bypass pipe (in the embodiment) 3.

The disadvantage of this device is that the filter is below the cementing zone, therefore, the zone of maximum hardening of cement stones is located only in the lowest part of the cemented interval, and replacing the cementing holes above the filter with a bypass pipe leads to significant pressure losses with a significant length and small diameter bypass pipe.

An object of the invention is to enable the filter to be placed in a cementing zone.

The goal is achieved by the fact that the device is equipped with a shoe nozzle with a shoe connected coaxially from below to the filter, the nozzle is made with upper and lower sealing flanges and an annular groove in the upper part under the upper sealing flange, the housing is made with ring upper and lower stops with ring stops placed on them seals and an annular groove between the stops with a latch located in it, and the cork plug is made with a tip with locking elements made with the possibility of hermetic fixing the tip in the hole of the upper flange, and the upper flange is fixed with a shear element in the housing above the filter, the lower flange is tightly pressed to the lower ring stop. the housing, the nozzle is mounted with the possibility of axial movement down into the shoe nozzle with the upper flange landing on the upper annular stop of the housing and placing the housing retainer in the annular groove of the nozzle, and the cementing holes are made in the shoe.

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A comparative analysis with the prototype and with other technical solutions shows that the device is distinguished by the presence of new features: the nozzle overlapping the filter has sealing flanges at both ends, the flange at the upper end of the nozzle is attached to the housing on shear pins. The pipe may be made in the form of telescopically inserted into each other pipes (sections), each of which is attached to the outer on shear pins. These features ensure that the proposed device meets the criterion of significant differences.

In FIG. 1 schematically shows a longitudinal section through a device at the time the cementation process is completed; in FIG. 2 is a view of the device after opening the filter; in FIG. 3 and k are the same, in an embodiment of a nozzle in the form of telescopically extendable sections.

A filter 4 is placed on the housing 1 with connecting nipples 2 and the perforated wall 3 (or the supporting strips). The pipe 5 has a flange 6 in the upper part, which is attached to the housing 1 on the shear pins 7 below the flange 6 on the outer surface of the pipe 5 groove 8 under the spring clip. A spring clip 10 is placed in the annular groove 9 of the housing 1. A flange 11 at the lower end of the nozzle 5 seals the housing stop A by means of an annular seal 12. Below the filter k, the inner surface of the housing forms an annular stop B with an annular seal 13 mounted on it to fit the flange 6. Housing 1 directly below the filter, it is coaxially connected by a shoe 1 to a shoe 15. The cement plug 16 has a tip 17 provided with a latch 18 for fixing the plug 16 to the flange 6.

In an embodiment of the nozzle 5 in the form of telescopically extendable sections 5, S, $, the annular retainer 10 is held by the protrusions 19 in the nipple 2, partially overlapping the annular groove 9. The pins 20 and 21 hold the sections 5 and are weighed.

The device operates as follows.

51 A device without a squeeze plug is lowered into a well on a casing string. At the end of the grouting process, the grouting plug 16 sits on the flange 6, and the tip 17 enters the hole of the flange.

For easy passage of the latch-latch. The top edge of the hole in the flange is rounded. The latch-latch 18 fixes the plug 16 to the flange 6. The rubber element of the plug seals the cavity of the nozzle 5.

Upon reaching the design pressure, the pins 7 are cut off. The nozzle 5 together with the plug 16 is guided into the shoe nozzle 1 and the flange 6 sits on the abutment A of the housing 1. The nozzle 5 is fixed in the lower position by means of the clamp 10 located in the annular groove 9. The annular seal 13 seals the cavity of the shoe nozzle 1, preventing cement slurry from entering the casing.

When the nozzle 5 is made in the form of telescopically extendable sections when the edge of the flange 11 hits the edge of the shoe 15, the pins 20 and 21 are cut off and the edge of the sections 5 destroys the protrusions 19. Section 5 is fixed by a latch 10.

At the end of the cementing process, the mouth is depressurized to reduce the pressure in the annular space.

Due to the difference in hydrostatic pressures in the column and the annulus, the liquid phase is filtered out from the grouting solution into the column. Excess fluid overflows from the column. Partial dewatering of the cement slurry in the zone closest to the filter increases the tightness of the annulus

cement ring load and bearing capacity.

Claims (2)

1. A casing cementing device comprising a hollow body with a filter therein Q with cementing holes, a nozzle located in the housing and a flow plug, characterized in that, in order to enable the filter to be placed in the area 5 cementing, it is equipped with a shoe nozzle with a shoe connected coaxially from below to the filter, the nozzle is made with upper and lower sealing flanges and an annular groove in the upper part under upper sealing flange, the housing is made with annular upper and lower stops with O-rings and an annular seal placed on them 5 by a groove between the stops with a latch located in it, and the cork plug is made with a tip with locking elements made with the possibility of tightly fixing the tip 0 in the hole of the upper flange, the upper flange being fixed with a shear element in the housing above the filter, the lower flange is tightly pressed to the lower annular stop of the body, the nozzle is mounted with the possibility of axial movement down into the shoe nozzle with the upper flange landing — on the upper annular stop of the body and the fixation in the housing in the annular groove of the pipe, and the cementing holes are made in the shoe. 2. The device according to claim 1, characterized in that the nozzle is made in the form of telescopically extendable sections, each of which is attached to the outer on shear pins. 5 5 ®ig.1 Fig. G figM