US2184393A - Paraffin removing device - Google Patents

Description

Dec. 26, 1939.

J. c. Luccous 2,184,393

PARAFFIN REMOVING DEVICE Filed Aug. 9, 1937 2 Sheets-Sheet l De@ 26, 1939- '.1. c. Luccous 2,184,393

PARAFFIN REMOVINQDEVICE Filed Aug. 9, 19557 y 2 Sheets-Sheet 2 Patented Dec. 26, 1939 PATENT OFFICE PABAFFIN REMOVING DEVICE John C. Luccous, Houston, Tex., assigner to Herbert C. Otis, Dallas, Tex.

Application August 9, 1937, Serial No. 158,168

12 Claims.

vThis invention relates to new and useful improvements in paraffin removing devices.

One object of the invention is to provide a device for removing parailin from the .walls of a well tubing including an improved scraper and an improved stop.

An important object of the invention is to provide an improved device for removing paramnincluding a scraper adapted to be actuated by the flow of the well uid ,or by iiuid pressure together with an improved stop therefor, which stop may be located at any point within the well tubing, whereby the device may be used in wells under various well conditions without removing the well tubing to properly locate a stop therein.

Another objectof the invention is to provide an improved stop for a, parailin scraper so arranged that it may be lowered into the well tubing from the surface and located at any suitable depth therein, and which is adapted to be removed from the tubing at any time l'without pulling or removing the tubing from the well,

whereby the bore of said tubing may be left open for the lowering of pressure bombs therethrough, or for other well operations.

A further object of the invention is to provide a removable stop which may be located at any suitable point within the well tubing, and an improved scraper which may be dropped through the tubing so as to be supported on said stop, there being a coaction between the scraper and stop, whereby said scraper will not dislodge or move the stop from its position, within the tubing.

Another object of the invention is to provide a paramn scraping device including, an improved stop on which a rest is arranged to be supported, and a scraper adapted to be dropped through the well tubing so as to be supported on said rest; the rest being so constructed that shock absorbing means may be incorporated therein if desired, whereby the shock or jar of stopping the falling scraper is absorbed by the rest. f

Still another object of the invention is to provide an improved stop and a parai'iln scraper arranged to be 1ifted by uid pressure to perform its scraping operation, said stop being constructed to be employed in combination with a flow restricting means for restricting the'tlow through the tubing, whereby the velocity of ow may be increased to assure lifting of the scraper within the tubing; the use of the restricting means being optional and particularly desirable in wells 'riaving a relatively low iiowing velocity.

A construction designed to carry out the inven- (ol. 1st-1s) tien win be hereinafter described, together with other features of the invention.

The invention will be more readily understood from a reading of the following specication and by reference to the accompanying drawings, in 5 which an example of the invention is shown, and wherein:

Figure 1 is a transverse, vertical, sectional view lof an apparatus, constructed in accordance with the invention. l0

Figure 2 is a transverse, vertical, sectional view of the stop in its released position,

Figure 3 is a horizontal, cross-sectional view taken on the line 3 3 of Figure 1,

Figure 4 is a horizontal, cross-sectional view, 15l

taken on the line 4-4 of Figure 1,

Figure 5 isa horizontal, cross-sectional view, taken on the line 5--5 of Figure 1,

Figure 6 is a view, similar to Figure 1 of the upper portion of another form of the apparatus,

Figure 7 is a continuation of Figure 6, showing the lower end of the apparatus, and

Figure 8 is a transverse, vertical, sectional view of still another form of the invention.

Figure 9 is a view partly in elevation and partly 25 l in section of the upper end of the well tubing, and showing the latch for the parafn scraper, and

Figure 10 is a horizontal cross-sectional view taken in the line Ill-Iii of Figure 9.--

In the drawings, the letter A designates a stop or obstructive device which is adapted to be set at any point within a well tubing B. The device comprises an elongate mandrel I0 having an axial bore II extending therethrough. The outer surface of the. mandrel is inclined outwardly toward its lower end to form a slip expanding surface I2. A tubular sleeve, or slip carrying member I3 is slidable -on the upper portion of the mandrel and an outwardly extending collar or flange I4 is preferably formed integral with the '40 lower end of said sleeve. A plurality of gripping elements I5 have their upper ends supported in radial slots I6 which are formed in the collar Il, and a retaining ring I1 which closes the outer end of said slots, contines the upper ends of said elements therein. Each gripping element extends through a radial slot I5' formed in an .annular flange I6' which is integral with the mandrel, and the elements are confined lwithin their respective slots by a confining ring I1 secured to 50 the iiange, as is clearly shown in Figure 1. Obviously, with this arrangement the gripping elements I5 are carried by-the tubular sleeve or member I3 and said elements may slide with relation to the mandrel Il.

Each gripping element I5 includes an arcuate gripping slip I8 and the inner surface of said slip engages the inclined surface I2 of the mandrel. The outer surface of each slip is formed with gripping teeth I9 which are adapted to move into engagement with the inner surface of the tubing wall and when engaged with said wall, pre vent an upward displacement or movement of the device.

The upper end of the tubular sleeve or slip carrying member I3 is provided with an outwardly extending annular flange I3 which flange has its lower end undercut as shown at 20 so as to receive a suitable fishing tool, as will be explained. Radial openings 2I are formed in the flange I3' whereby a lowering tool may be engaged over said flange and pins (not shown) pass through openings in said tool (not shown) and through the openings 2|, whereby the sleeve or member I3 is connected to the lowering tool. When it is desired to lower the device within the well tubing B, a lowering tool is connected to the sleeve I3 by pins (not shown) as explained, and thus the entire device is suspended from such lowering tool. When so suspended, the parts assume the position shown in Figure 2 with the mandrel lowered with relation to the slips I 8, whereby said slips engage the upper portion of the inclined outer surface I2 of said mandrel, which places the slips in their retracted position. In this position, the tops of the slips I8 are engaged with the underside of the flange I1' on the mandrel, whereby said mandrel is suspended from the slips.

The device may then be lowered through the tubing B without the slips I8 engaging the side wall of said tubing and the lowering continues until the device reaches an elevation within the tubing at which it is to be set. In order to set the slips, the line which ls carrying the setting tool is suddenly slackened, which permits the sleeve I3 and the gripping elements I5 carried thereby to move downwardly more rapidly than the mandrel I0, whereby the slips I8 ride downwardly on the inclined surface I2 of said mandrel. 'I'his downward movement of the slips with relation to the mandrel causes said slips to be moved outwardly into engagement with the wall ofthe tubing B. A jar is then imparted to the lowering tool, which will cause the pins extending through the openings 2I to be sheared.

The running tool, after being disconnected from the member I3, is then lowered to engage the flange I4 and continued jarring on said flange causes the slips I8 to ride downwardly on the inclined surface I2 to expand said slips into tight engagement with the tubing wall. The lowering tool is then raised and removed from the tubing. 'I'hus it will be seen that the device may be lowered into the tubing and set at any point therein.

l It is pointed out that if desired the lowering tool may be connected to the mandrel I 0 instead `until the. shear pins passing throughihelopenings 22 in the mandrel are broken,after .which the loweringtool may be removed.` I

After `the stop or obstructing. device I Il' has been set in its proper position within the tubing BL andafter the lowering tool has been removed, a scraper rest C which may have incorporated therein a shock absorber, is lowered through the tubing so as to be supported by the device I0. This shock absorber comprises an elongate tubular body 23, which is of such diameter that its lower end may telescope the upper end of mandrel IIJ and the sleeve I3 so that its lower end may rest upon the collar or flange .I4. An internal flange 24 is formed within the bore of the body 23, while the upper end of the bore of said body is internally screwthreaded at 25. A sleeve 26, having an outwardly directed annular flange 2'I at its lower end, which flange may be formed by screwing a collar onto the lower endof the body, is slidable vertically within the upper portion of the body 23 and upward displacement of the sleeve from said body is prevented by a retaining collar 28 which is threaded into the upper end of the bore of the body. As is clearly shown in Figure l, the sleeve 2B is slidable through the retaining collar 28 and its flange 21 is adapted to engage the under side of said collar. A coiled spring 29 is confined between the sleeve 26 and the internal shoulder 24 within the body 23 and this spring exerts its pressure to constantly urge the sleeve 26 to its uppermost position (Figure 1).

After the stop A and the rest C have been positioned within the tubing B, as has been explained, a paraffin scraper 30 is dropped through the tubing B. This scraper is preferably cylindrical in cross-section, being provided with flanges 3I at its upper and lower ends. The external diameter of the flanges is less than the diameter of the bore of the tubing B, whereby a clearance between the tubing wall and the outer surface of the flanges is had.` The upper flange 3| of the scraper is formed with inclined grooves 32 whereby cutting teeth are provided and the lower flange may, if desired, be formed with similar grooves. The scraper 30 is preferably metallic and obviously as it falls downwardly through the tubing it will gain considerable momentum. As said scraper drops, it will contact the upper end of the sleeve 26 whereby said sleeve will be forced downwardly against the pressure of the spring 29 and thus, it will be seen that the spring absorbs the shook of the sudden stopping of the scraper. The jar of said scraper striking the shock absorber of the rest will be imparted to the sleeve 23 thereof and through this sleeve, transferred to the flange or collar I4 of the slip carrying member I3. This downward jar or thrust is, therefore, received by the slip carrying member, rather than by the mandrel and the tendency is to more rmly set the slips. Such arrangement eliminates the possibility of the jar, imparted by the sudden stopping of the scraper, dislodging the stop from its position within the tubing. It is noted that in some instances, it may be desirable to move the scraper downwardly in the tubing by fluid or other pressure instead of depending upon gravity to lower said scraper.

After the scraper 30 has been lowered into the tubing, the connections (not shown) at the upper end of the tubing are opened to cause flow of fluid upwardly through the tubing B at sufficient flow velocity to act against the underside of the scraper 30 to raise the same and move it upwardly through said tubing, whereby the peripheral edge of the scraper contacts the paraffin on the wall of the tubing to scrape said paraffin therefrom. The top of the scraper 30 is preferably recessed as shown at 33 whereby a sharp peripheral edge is formed, which edge performs the scraping action. After the wall of the tubing has been cleaned of parafhn by the upward travel of the scraper, said scraper may be permitted to fall to its position on the rest C and the rate of flow again cut down until only a normal production flow will pass upwardly through the tubing. 'Ihe clearance between the scraper 30 and the tubing wall may be such as to permit this normal cw of fluid upwardly through the tubing without lifting said scraper. This permits the apparatus to remain in the tubing until such time as i sufficient paramn has accumulated to make it desirable to again scrape the same from the tubing wall, at which time the connections at the upper end of the tubing may again be opened to raise the scraper. It is specifically noted that it is preferable that the normal flow of the well does not raise the scraper as the clearance between said scraper and the tubing wall permits such normal flow. Under such conditions, it is necessary that the ow velocity be increased so that a pressure differential is set up by this increased velocity across the scraper, which pressure differential moves the scraper upwardly in the well tubing.

When it is desired to remove the device from the well tubing, the scraper 30 is lifted by the fluid to the well surface, and subsequently removed from the tubing. The upper end of the sleeve 26 of the rest C is provided with an undercut flange 26,', whereby a suitable fishing tool (notshown) may be lowered through the tubing and engaged beneath said flange, whereby the rest may be lifted and removed from the tubing. After the rest is removed, the shing tool (not shown) is again lowered through the tubing and is engaged beneath the flange I3' on the upper end of the sleeve or slip carrying member I3. A

40 downward jar on the mandrel I0 and an upward pull on this member by means of the fishing tool will raise the gripping slips I8 with relation to the mandrel I0, whereby said-slips riding up the inclined or tapered surface I2 of said mandrel 4,5 are retracted from engagement with the wall of at one depth and at a later date set at a different depth within the same tubing. The removability or the stop, together with the ease in set- A ing at any desired point, are important features of the invention. The position at which the stop is set will'vary with each iield and well, said stop being positioned in the tubing a suicient distance below the lower limits of the parafdn deposit to permit the flow to attain sufficient velocity to lmove the scraper upwardly to perform the scraping function satisfactorily.

In some cases, it is desirable to keep the scraper 30 out of the tubing B when said scraper is not in use and in such cases, a suitable means may be provided for receiving the parain scraper and holding the same from falling back into the tubing. Such a means may be in the form of a 'spring pressed latch D located in a lubricator E (Figure 9) above the usual flow crots of the upper end of the tubing. The scraper would be carried upwardly past the flow cross into the lubricator ily the ii'ow of the fluid. Upon entering the lubricator, said scraper would engage the latch and be held within said lubricator out of the flow line until such time as .it is again needed.

Conditions may arise where the velocity of the flowing fluid is not sumcient to lift the scraper 30 and in such instances, it would be desirable to utilize a choke or tlow bean 35 (Figure 7). This bean is mounted in the lower end of the mandrel which is formed with an extension I0 as is clearly shown in Figures 6 and 7. Suitable packing cups or other packing elements 36 are mounted on the extension I0 below the gripping element I5 and these elements serve to pack off the annular space between the mandrel I0 and the tubing B, whereby all of the fluid must flow upwardly through the bore Il of the mandrel. T'he flow bean 35 is provided with an axial bore 31 of a desired diameter, whereby the restriction of the flow at this point may be properly controlled. The employment of a bean 35 increases the velocity of the flow so that the upward movement of the scraper 30 is assured. y,

Although the rest C incorporating the shock absorber therein is desirable it is not essential that the :tame be used. When it is eliminated, a scraper 30', as shown in Figure 6, is employed. This scraper is constructed in substantially the same manner as is the scraper 30 except that it is provided with a rest in the form of a depending annular skirt or sleeve 38 which sleeve is `ar ranged to telescope or-move downwardly over the upper end of the mandrel I0 and the sleeve I3, with its lower end resting on the collar Il of the slip carryingmember I3. An axial stem 39 may be formed integral with the upper end ofthe scraper 30' and an undercut shoulder or fishing neck l0 is formed at the upper end of the stem. The stem and neck facilitate the removal of the scraper 30' by means of a iishing tool. The operation of the scraper 30 is exactly the same as that of the scraper 30 shown in Figure 1.

The parain scraper 30, as shown in Figure l, may be lowered into the tubing without the rest C having the shock absorber located therein. In place of the shock absorber, an annular rest or casing 6I is first lowered through the tubing so as to be supported on the flange Il of the slip carrying sleeve or member I3. This annular rest has its upper end reduced and provided with a fishing neck 42, whereby said rest may be removed by a suitable shing tool (not shown) when not in use. In this instance, the scraper 30 would drop through the tubing B and engage upon the upper end of the rest 4I which is substituted for the rest C.

What I claim and desire to secure by Letters Patent is:

1. In combination in a paraffin removing device, a stop arranged to be mounted at any desired elevation within a well tubing. anda paraffin scraper having -scraping blades and a depending sleeve arranged to be dropped through the tubing and supported by the stop, said sleeve telescoping the upper/end of the stop.

. 2. A paramn removing device including, a removable stop locked at any suitable point in the well tubing, and a parailin scraper having a deremovably located within the well tubing, a tubular rest having its lower end telescoping the upper end of the stop and supported by said stop, and a paraffin scraper supported on said rest and arranged to be lifted by fluid pressure.

4. In combination, a stop `having retractible means for locking it in a well tubing at any desired elevation, a paramn scraper rest removably mounted on said stop in engagement with the locking means, whereby a downward thrust upon the rest is transmitted to said locking means to prevent displacement of the stop.

5. In combination, a stop having retractible means for locking'it in a well tubing at any de-v sired elevation, a paraffin scraper rest removably mounted on said stop in engagement with the locking means, whereby a downward thrust upon the rest is transmitted to said locking means to prevent displacement of the stop, and a parafn scraper engaging said rest and arranged to be moved upwardly in the tubing by the wellfluid.

6. A paraffin removing device including, a stop having means for engaging the wall of the well tubing at any point irrespective of the tubing collars for securing said stop at any desired elevation, a shock absorber carried by the stop, and a paraffin scraper arranged to' strike and rest upon the shock absorber.

'7. A paraflin removing device including, a stop having means for engaging the wall of the ywell tubing at any point irrespective of the tubing collars for securing said stop at any desired elevation, and a parain scraper having scraping blades and a depending annular skirt arranged to telescope the upper end of the stop and come to rest on the fastening means of said stop.

-l .8. In a parain removing device the combination of, a stop having means for' engaging the Wall of the well tubing at any point irrespective of the tubing collars for securing said stop at any desired elevation, a tubular rest arranged to telescope the stop and come to rest on the fastening means thereof, and a paraiin scraper arranged to engage the upper end of the rest, whereby its downward movement is arrested.

9. In a paraflin removing device the combinanation of, a, stop provided with vertically movable locking means for engaging the wall of a well tubing for fastening the stop at any desired elevation, and a scraper rest having a depending portion arranged to overhang the upper end of the stop and rest upon said locking means, whereby the rest telescopes the stop and' forces the locking means into tighter engagement with the well tubing, and a scraper sustained by the rest at the lower end of the scraping stroke.

10. In a parafln removing device the combination of, a stop including an elongate mandrel having an annular slip expanding surface on its lower end and provided with an axial bore extending therethrough,v slips mounted on the mandrel, and a slip carrier slidable on the mandrel and having an annular collar, in combination with a scraper rest having a depending cylindrical portion arranged to receive the upper end of the stop and rest upon the collar of said slip carrier.

11; In a parain removing device the combination of, a freely adjustable stop having eX- pandible gripping means for gripping the inner wall of a well tubing to position said stop at any desired elevation in said well tubing, means carried by said stop for actuating the gripping means into gripping engagement with said tubing, and a parafiin scraping device having peripheral scraping blades thereon and movable vertically in said tubing, and means engaging and resting upon the gripping actuating means for arresting the scraping device at the bottom of its down stroke, whereby thrust resulting from the down- Ward movement of said device acts to force the gripping means more tightly into engagement with the Wall of the tubing.

12. In a paraffin removing device the combination of, a stop member having means for gripping the wall of a Well tubing, means for actuating said gripping means, a shock absorber mounted on said stop and having a portion engaging said actuating means, and a paraflin scraper arranged to strike upon the shock absorber, the impact of the paran scraper being transmitted to said gripping means to more firmly secure the stop in the tubing.

JOHN C. LUCCOUS.

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