RU2081997C1 - Non-return washing valve - Google Patents

Abstract

FIELD: oil production industry. SUBSTANCE: this relates to well head equipment and can be used in oil production wells operated with immersed pumps. Non-return valve has body with upper and lower connecting threads. Body hollow is covered atop by baffle grate. This hollow communicates with outside space through side passage having vertical section. Also made in body is longitudinal passage communicating with hollow. Installed in vertical section of side passage and in upper part of longitudinal passage are seats in the form of taper bushes having cylindrical sections in their lower parts. Located in hollow is ball-type valve which can be found in one or other seat and in changing direction of fluid flow motion, ball-type valve can replace from one seat to other. At running down of pumping unit at speed of 0.15-0.25 m/s, ball-type valve being on seat in side passage only lifts up to pass fluid from intertube space into lifting tube string. Taper bushes can be installed at one level and fixed in passages by thread made on cylindrical sections and correspondingly in mating sections of passages. Baffle grate has concave lower surface and radial protrusions over periphery for centering in circular bore of body. Vertical slots are provided in thread for passing of protrusions when installing grate into bore. At lifting of equipment, pump is isolated by ball-type valve. EFFECT: high efficiency. 4 cl, 1 dwg

Description

 The invention relates to downhole equipment and can be used in the oil industry in wells, usually equipped with submersible electric centrifugal, screw or diaphragm pumps.

The prior art well borehole valve comprising a housing with upper and lower connecting threads, an internal cavity and lateral and longitudinal channels connected to the internal cavity, a saddle mounted in the lateral channel and a shut-off element installed with the possibility of placement on the saddle [1]
A disadvantage of the known downhole valve is the complexity of its design and control of its operation.

A non-return valve is also known, comprising a body with upper and lower connecting threads, an internal cavity blocked by a selective grill in the upper part, and side and longitudinal channels communicated with the internal cavity, a seat installed in a vertical section of the side channel, and a ball valve located on the seat with the ability to move through the internal cavity and placement in the longitudinal channel and vice versa [2]
A disadvantage of the known non-return valve is that it does not overlap the longitudinal channel when the ball valve is placed in it, which entails the ingress of liquid into the pump when lifting the column of lifting pipes.

 The objective of the present invention is to obtain a technical result, expressed in ensuring the overlapping of the longitudinal channel when placing a ball valve in it.

 This technical result is achieved due to the fact that the backwash valve comprising a body with upper and lower connecting threads, an internal cavity overlapped in the upper part by a selective grill, and side and longitudinal channels communicating with the internal cavity, a saddle mounted in a vertical section of the side channel, and a ball valve located on the saddle with the ability to move through the internal cavity and placement in the longitudinal channel and vice versa, is equipped with an upper th part of the longitudinal channel with a seat under the ball valve, the bottom surface of the baffle is made concave, and the seats are made in the form of conical bushings.

 It helps to obtain the specified result that the saddles are installed in the channels at the same level.

 Tapered bushings have cylindrical sections in the lower parts.

 In particular cases of valve execution, tapered bushings can be installed in the channels on the thread, and the thread can be made on their cylindrical sections and on the counter sections and on the counter sections of the channels, respectively.

 The drawing shows a longitudinal section of a backwash valve.

 The backwash valve includes a housing 1 with upper and lower connecting threads 2, 3, which are used to integrate the valve into the column of lifting pipes (tubing). A cavity 4 is made in the housing 1, which is overlapped in the upper part by the fencing grill 5. The lower surface 6 of the fencing grill 5 is concave, and the grill 5 itself has passage channels 7 and protrusions 8 along the periphery, due to which it is centered in the annular bore 9 made in the cavity 4 under the thread 2. To ensure the passage of the protrusions 8 in the thread 2 made longitudinal grooves (not shown). The lateral and longitudinal channels 10, 11, connected with the cavity 4, are made in the housing 1. The lateral channel 10 has a vertical section in which a saddle 12 is mounted. A saddle 13 is installed in the upper part of the longitudinal channel 11. The saddles 12 and 13 are made in the form of conical bushings. The ball valve 14 is placed on the seat 12 in the initial position and has the ability to move through the cavity 4 and placement in the longitudinal channel 11 on the seat 13 when fluid is supplied through the side channel 10 from the annulus. When the submersible pump is turned on under the action of an upward flow of produced fluid, the ball valve 14 is able to move through the cavity 4, vice versa, from the seat 13 to the seat 12. The preferred embodiment of the valve should be considered such that the seats 12 and 13 are installed at the same level. In the particular case, the conical bushings (saddles) have cylindrical sections in the lower parts. Tapered sleeves can be installed in the channels 10, 11 on the thread, which can be performed on their cylindrical sections and on the counter sections of the channels 10, 11, respectively. This design of the conical bushings allows them to be made replaceable, for which purpose, for example, protrusions or grooves (not shown) can be provided in their upper parts (ends).

 The backwash valve operates as follows. When the pump assembly is lowered into the well, a ball valve 14 pre-installed on the seat 12, under the action of the well fluid entering the side channel 10, rises on the seat 12 and passes it into the lifting column (tubing). The design of the seat 12 provides at a descent speed of the pump assembly of 0.15-0.25 m / s only a lift of the ball valve 14 on the seat 12. After starting the submersible pump, the ball valve 14 is pressed against the seat 12 and holds the liquid column in the lifting column (tubing). If it is necessary to carry out technological operations or underground repairs, liquid is pumped from the surface into the annular space, which, with its pressure, moves (throws) the ball valve 14 into the seat 13, thereby opening the side channel 10. This is facilitated by the concave surface 6 of the baffle plate 5. Re-inclusion submersible pump allows you to move the ball valve 14 back to the seat 12.

 The use of the invention allows multiple movements of the ball valve 14 from the seat 12 to the seat 13 and vice versa, which makes it possible to organize a particular flushing scheme, and when lifting the assembly, isolate the submersible pump from the liquid entering the column of lifting pipes (tubing). This non-return flush valve is proposed to replace the valves currently used, which have a number of disadvantages, the main of which are the separation of an existing well from work in the event of, for example, breakage and falling into the column of the scraper lifting pipes. In order to restart the well into operation, it is necessary to lift the pumping line to the surface, carry out the necessary repair and restoration work and again lower the pumping line into the well. Especially effective is the use of the proposed backwash valve for hot pumping wells, at low pressures.

Claims (5)

 1. The backwash valve, comprising a housing with upper and lower connecting threads, an internal cavity blocked in the upper part by a breaker grill, and side and longitudinal channels communicated with the internal cavity, a seat installed in a vertical section of the side channel, and a ball valve located on a saddle with the ability to move through the internal cavity and placement in a longitudinal channel and vice versa, characterized in that it is equipped with a saddle mounted in the upper part of the longitudinal channel under the ball valve n, the lower surface of baffle concave grating, and a seat formed as conical sleeves.  2. The valve according to claim 1, characterized in that the seats are installed in the channels at the same level.  3. The valve according to claim 1 and / or 2, characterized in that the conical bushings have cylindrical sections in the lower parts.  4. The valve according to paragraphs. 1 to 3, characterized in that the tapered bushings are installed in the channels on the thread.  5. The valve according to paragraphs. 3 and 4, characterized in that the thread is made on the cylindrical sections of the conical bushings and on the reciprocal sections of the channels, respectively.