RU2336410C2 - Hydromechanical and multi-purpose scraper - Google Patents

Abstract

FIELD: oil and gas production industry.

SUBSTANCE: invention is related to oil and gas production industry and applied to clean walls of casing string. Hydromechanical and multi-purpose scraper (hereinafter HMPS) consists of hollow cylindrical case that includes hollow plunger in the cavity. Plunger is hydraulically actuated and returned to shipping position by pullback spring. The cylindrical case is provided with connecting threads at the ends. The hollow cylindrical case is provided with windows with spring-controlled scraping elements. Spring-controlled scraping elements are pushed by means of hollow plunger. Ends of hollow plunger are situated in shells. Top shell is connected with pressure test seat. Choke element is retracted after casing string walls are cleaned. The HMPS is provided with hollow plunger to ensure "direct" and "back" flush and pressure test of tubing with subsequent removal of pressure test element.

EFFECT: improved quality of pipe cleaning.

3 dwg

Description

The invention relates to the oil and gas industry and can be applied when cleaning the walls of the pipes of the production casing, during repair work from various scaling, corrosion deposits, and also paraffin deposits.

Background to the invention. Analysis of the current level of technology in this field showed the following.

A device for processing walls of a well is known (RF patent No. 2189432, 7 ЕВВ 37/02), containing a hollow body with connecting threads at the ends. Concentrally mounted to the housing is a casing having the possibility of axial rotation. On the casing mounted blades with a reinforced working surface.

A disadvantage of the known device is that the quality of cleaning the inner surface of the walls of the production string is too low to install packers such as PRK, PGRK, PGRZ, packer sleeves, M1X. In addition, the column is cleaned throughout the descent, and not the selected interval, which may be impractical and will entail additional costs.

A device is known for cleaning the inner surface of casing strings (Autost. St. USSR No. 1820654, ЕВВ 37/02), which consists of a hollow body of a scraper assembly with recesses on the outer surface, hydraulically connected by radial channels with its cavity. The device is equipped with self-sealing cuffs located in the recesses between the body and the cutting dies.

The disadvantage of this device is that its device itself does not allow washing the bottom of the well.

A device for cleaning the inner surface of the casing strings (RF patent No. 2138618, 6 ЕВВ 37/02), issued by us as a prototype, consisting of a hollow cylindrical body, in which a holder with windows in which are mounted with the possibility of radial reciprocating movement tool holders with cutting elements.

The disadvantage of this device is that flushing during cleaning occurs through the cracks between the toolholders and windows, and its device itself does not allow flushing of the bottom of the well.

The objective of the invention is the combination of operations for washing the bottom and cleaning the walls of the production string in a given interval and improving the quality of cleaning, as well as the possibility of crimping tubing, reducing labor and economic costs when repairing wells.

The problem is solved by the described hydromechanical universal scraper (hereinafter referred to as SSMU), consisting of a hollow cylindrical body, carrying a plunger in its cavity, which is driven by hydraulic action, and returns to the transport state using a return spring.

The cylindrical body is made with connecting threads at the ends. In the hollow cylindrical case there are windows in which spring-loaded scraper elements are located.

What is new is that the plunger is hollow, the spring-loaded scraper elements being advanced using this hollow plunger. The ends of the hollow plunger are in the sleeves, while the upper sleeve is connected to the crimping seat, and the lower sleeve is connected to the sleeve of the tubing.

New is the fact that the SSMU is made with a hollow plunger, thereby providing the possibility of “direct” and “back” washing and crimping of the tubing with subsequent extraction of the crimping element.

Also new is the fact that the scraper contains a waste choke element for closing the hollow plunger, moving it and extending the spring-loaded scraper elements and a return spring for returning the hollow plunger to its original position, as well as a spring for returning the spring-loaded scraper elements to their original position. In this case, the waste choke element is removed after cleaning the walls of the production casing.

An analysis of patent and scientific and technical literature did not reveal technical solutions with a similar set of essential features, which allows us to conclude that the proposed solution is new and technical.

The design of the hydromechanical universal scraper is illustrated by the drawings:

 figure 1 schematically shows the proposed device in its original position;

 figure 2 presents a waste choke element;

 figure 3 presents the crimping element.

SSMU contains a hollow cylindrical body 1 with connecting threads at the ends, with windows 2 in which there are spring-loaded scraper elements 3, extendable with the help of the hollow plunger 4. The ends of the hollow plunger 4 are in the sleeves, the lower sleeve 5 is connected to the tubing sleeve 6, and the upper sleeve 7 is connected to the crimping seat 8, and the hollow plunger 4 is returned to its original position by the return spring 9. When the hollow plunger 4 is closed with the thrown fitting element 10, the hollow plunger 4 moves down and extends the spring-loaded e scraper elements 3 that when moving NSMU of production casing 11 is purged. If necessary, crimping the tubing 6 use a crimping element 12 (ball, cone, etc.). Springs that return the spring-loaded scraper elements 3 to their original position, fasteners and process connectors are not shown in the drawing.

Universal hydromechanical scraper works as follows.

On the tubing string 6, the device descends into the well. Upon reaching the desired depth, the crimping element 12 is thrown into the tubing 6, after which the tubing 6 is crimped (if necessary, crimping), then the crimping element 12 is washed or removed by the winch. After that, a thrown fitting element 10 is thrown into the tubing 6. The throwing fitting element 10, freely passing through the crimping seat 8, overlaps the cross-section of the hollow plunger 4 and, when pumping the liquid, provides resistance to raise the pressure above the hollow plunger 4. The pressure on the hollow plunger 4 is created using flushing pump (not shown in the drawings). The hollow plunger 4 moves downward, advancing the spring-loaded scraper elements 3.

After creating pressure and circulating the fluid using flushing equipment, the SSMU, lowered into the well at the tubing string 6, moves along a predetermined cleaning interval. At the end of the cleaning interval, the fluid supply is stopped, the pressure drops and the return spring 9 lifts the hollow plunger 4 to its original position. The spring-loaded scraper elements 3 also return to their original position, SSMU takes the transport position. Thus, the cleaning operation can be repeated as many times as necessary. After cleaning the entire interval, the waste choke element 10 is washed backwash or removed by a winch, after which it is possible to flush the bottom of the well. The diameter of the internal section of the hollow plunger 4 (about 40 mm), which easily allows for direct and reverse flushing.

The application of the invention will allow for better cleaning of the walls of the production casing (since the scraper elements are “rigid” and not “floating”, i.e., SSMU seeks to clean the casing along the “correct” circle uniformly). The combination of cleaning the walls of the production casing and flushing the bottom (which was previously impossible) will significantly reduce labor and economic costs for well repair. The invention also allows you to compress the technological tubing with subsequent washing or removing the crimping element (ball, cone, etc.).

The use of the invention will significantly reduce the labor and economic costs necessary for well repair, and the repair will be carried out more efficiently than the repair, in which any other equipment would be used to clean the walls of the production casing. In turn, this will reduce the overhaul period and improve the quality of production wells.

Claims (1)

A universal hydromechanical scraper, consisting of a hollow cylindrical body with connecting threads at the ends for connection with sleeves and with windows for spring-loaded scraper elements made with the possibility of their extension from the windows, characterized in that the hollow cylindrical body contains a hollow plunger for the possibility of passage of the process fluid, conducting a “direct” or “backward” flushing of the bottom of the well and an crimping element for crimping, while the hollow cylindrical body is connected to the upper guards Zoya with a crimping seat, the lower sleeve is connected to the sleeve of the tubing, and the ends of the hollow plunger are in the sleeves, and the scraper contains a threaded fitting to block the hollow plunger, move it and extend the scraper elements and a return spring to return the hollow plunger to its original position , as well as a spring to return the spring-loaded scraper elements to their original position.

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