RU2200226C2 - Gear to expand pipes - Google Patents

Abstract

FIELD: expansion of articles manufactured from profile pipes in holes. SUBSTANCE: invention specifically refers to profile shut-off valves. Gear includes body with central valve Eccentric members in the form of bushings are put on body. Bushings have collars and engage one another. Eccentric bushings are displaced one relative another in central plane through 120 degrees. Cylindrical rollers possessing conical outer surfaces are mounted on eccentric bushings. Upper and lower bushings are joined to body. Thrust rings are positioned between upper faces of rollers and lower faces of collars. Profile pipes expanded beforehand by hydraulic pressure are expanded in hole by rotation of gear with formation of axial load on it and by simultaneous washout. EFFECT: raised serviceability of gear. 2 dwg

Description

 The invention relates to the field of drilling and overhaul of oil and gas wells and is intended, in particular, for flaring profile overlaps installed in wells.

 A device for expanding pipes is known, including a housing with a central channel and a rolling element in the form of a cone mounted on an axle inclined to the axis of the device (1).

 A disadvantage of the known device is the rapid wear of the rolling element due to its abrasive interaction with the expandable overlap. In this case, under the influence of large specific loads on the contact area of the rolling element with the expandable overlap, their mutual abrasion occurs.

 Closest to the invention in technical essence is a device for expanding pipes in wells, comprising a housing with a central channel and eccentric elements on which the rollers are mounted (2).

 The main disadvantage of this device is also the low availability due to the rapid wear of the housing due to the abrasion of its eccentric elements by the rollers during their rotation, which does not provide the necessary inner diameter of the expandable pipe.

 These disadvantages do not allow the use of the known device for expanding thick-walled profile pipes, especially their cylindrical ends, which require the use of large axial loads and torque. At the same time, frequent replacement of worn-out cases with new ones will be inevitable, which results in large material and time costs.

 The purpose of the invention is to increase the operability of the device when expanding devices made of profile pipes with cylindrical ends.

 This is achieved by the fact that in the described device for expanding pipes, including a housing with a central channel and eccentric elements on which the rollers are mounted, according to the invention the eccentric elements are made in the form of bushings that engage with each other for their joint rotation with the housing.

 These differences completely eliminate the wear of the eccentric elements of the housing; in this case, eccentric bushings are subjected to abrasion, which can be replaced by others as they wear. Thanks to this, a more accurate obtaining of the required flare diameter is achieved.

 In FIG. 1 shows a General view of the device in longitudinal section; figure 2 is a section aa in figure 1.

A device for expanding pipes (Fig. 1) comprises a cylindrical body 1 with a central channel 2. For connecting the device to downhole equipment, the body has a sleeve 3 and a nipple 4 ends with threads 5 and 6, respectively. On the housing 1, eccentric bushings 7 are installed in series (FIGS. 1, 2) having thrust collars 8 and interconnected by cams 9 with a displacement in the diametrical plane of 120 ^° relative to each other (FIG. 2). On the eccentric bushings 7, cylindrical rollers 10 are installed (Fig. 1) having conical surfaces 11, and thrust rings 12 are placed between the upper ends of the rollers 10 and the lower ends of the shoulders 8. On the inner surface of the rollers 10 are made annular grooves 13 filled with graphite grease. The upper and lower eccentric bushings 7 by means of threads 14 and 15 are respectively connected to the housing. 1 for joint rotation with it.

 The device operates as follows.

 On the drill pipe string 16 (FIG. 1), the device is lowered into the borehole 17 all the way to the upper cylindrical end (not shown) of the profile casing 18. Then, by rotating the string 16 and creating an axial load, the device is pushed through the profile pipe 18 previously expanded by hydraulic pressure, while washing the well 17 through the central channel 2 of the housing 1. In this case, the rollers 10, rolling along the inner surface of the profile pipe 18 with their conical 11 and cylindrical 19 surfaces, expand it to a tight hold tiya its walls to the walls of the well 17.

Due to the placement of the rollers 10 in the form of several sections eccentrically displaced relative to each other through 120 ^° , uniform expansion coverage is achieved at the same time as a large portion of the pipe in a helical manner, as a result of which the inner surface of the pipe 18 and its cylindrical ends is smooth without transverse scars. At the same time, the time to complete work and energy consumption is significantly reduced.

 Thanks to the ability to replace eccentric bushings, the service life of the device is increased.

Sources of information
1. USSR author's certificate 1295799, E 21 B 29/10, B 21 D 39/14, 1995

 2. USSR author's certificate 905425, E 21 B 29/10, 1982

Claims (1)

 A device for expanding pipes, comprising a housing with a central channel and eccentric elements, on which cylindrical rollers are installed having conical surfaces, characterized in that the eccentric housing elements are made in the form of bushings having collars and engaged with each other, with the upper and the lower bushings are connected to the housing, and thrust rings are placed between the upper ends of the rollers and the lower ends of the shoulders.

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