US2141508A - Paraffin cleaner - Google Patents

Description

Patented Dec. 27, 1938 :PATENT OFFICE 2,141,508 A PARAFFIN CLEANER Glenn R. Buckley and Walter A. McGrew, Oklahoma City, Okla.

Application March 25, 1937, Serial No. 132,921

2 Claims.

This invention relates to certain improvements in devices Afor removing parain from the interior of oil well tubing, and the like.

Devices generally used for this purpose at present have one common difficulty. After they have been lowered into the well and the return movement has been started, 'and a considerable amount of paraflin accumulates above the scraper, a high degree of vacuum is created in the tubing below the scraper.- This vacuum causes oil to be drawn into the lower end of the tubing and raised in the tubing some thirty-two or thirtythree feet. Further upward movement of the scraper tends to increase the vacuum, but the back pull of the oil in the tubing causes parallin to force its way-past the scraper in the tubing and return into the well.

It is the chief object of our invention, therefore, to-provide a device of this class which ernbodies an air passage which affords communication between the space` below the scraper and the space above the paraiiin which is being carried upward by the scraper.

Another object is to provide a novel sealing arrangement which prevents the paraffin from.

passing the scraper as it is raised in the tubing. A Another object is toprovide a. device of this class embodying two or more scraper elements which serve to doubly seal the scraper against the sides 4of the tubing. f

Other objects of the invention will be fully understood by a consideration of the following detailed description when read in connection with the accompanying drawing which form a part of this application. The drawing is to be considered illustrative and not restrictive.

In the drawing:

Figure 1 is a side elevation of the device in section, showing it in operative position within a well tubing;

Figure 2 isa sectional view of the upper end of the uppermost pipe section used in connecl tion with our device, and shows the ports which afford communication with the space in the tubing below our cleaner;

Figure 3 is a top plan view of the sealing assembly4 shown in its relation to its supporting member, and to its positioning sleeve, the latter two elements being shown in section; and,

Figure 4 is a top plan view of the disc assembly, shown in relation to its supporting member, which latter is shown in section.

The invention comprises an upper disc supporting member I threaded exteriorly at its upper end, and threaded interiorly at its lower end, and

(ci. 16s-Lis) l having a, longitudinal passage 2 throughout it length. A second disc supporting member 3 is threaded at its upper end exteriorly for convnection to the lower end of the member I, and

is also exteriorly threaded at its lower end, and 5 has a similar passage Il throughout its length. Each of the members is provided with an annular shoulder intermediate its ends, and the shoulder of each member serves to support a disc assembly, designated as a whole by the numeral 10 5, and a sealing assembly, designated as a whole by the numeral 6.

At its lower end -the supporting member 3 carries a. valve cage 1, which has the usual annular conical valve seat 8 near its upper end, and l5 which houses a usual ball valve 9. The lower end of the valve cage is open with the exception of a pin I0, or like member, which serves to retain the ball in the cage.

Referring to` Fig. 4, each disc assembly 5 in- 20 cludes a hinge member II to which are suitably hinged four sections I2,l I3, I4 and I5, which together form a substantially disc-1ike scraper.

Referring to Fig. 3, each sealing assembly 6 comprises a central hinge member I6 to which 25 are' hinged four flappers I1, I8, I9 and 20. Both the hinge members II and I6 are centrally bored to fit snugly on the reduced Shanks of the members I and 3. The two assemblies 5 and 6 are held tightly on their respective shoulders and 30 against each other by similar sleeves 2| and 22, the lower'ends of which seat on the hinge members I6, and the upper ends of which are con. tacted by the lower ends of the adjacent memf bers I, with the exception of the uppermost sleeve 35 2 2, the upper end of which is contacted by the lower end of a pipe section 23. The lower ends of each of said sleeves 2I and 22 are preferably provided with suitably spaced prongs 21, 28, 29 and 30 (Fig. 3) which are adapted to partially 40 encompass th'e central ring portions of the members I6,/as shown. l

We contemplate using a plurality of the pipe -sections 23 above the scraper proper. If approximately one 'hundred feet of the tubing is to be 45 cleaned at one time then approximately one hundred feet of the pipe sections 23 will be used, and

to the uppermost section 23 will be attached a pipe section 24. which is provided at its upper end with a plurality of ports, all of which are designated by the numeral 25, and with threads for securement to the lower end of the usual operating rod 26.

In assembling the device the valve cage 1 is 4secured to the lower end of the -member 3 and 55 the lower disc assembly 5 is slipped over the reduced upper shank of member 3 and allowed to drop on the intermediate shoulder. The sealing assembly 6 is then likewisesplaced on the reduced shank of the member 3 anims so positioned that its nappers I'I, I8, I9 and5"2|l cover the spaces between the edges of the hingm \sec tions I2, I3, I4 and I5 of the disc assembly, and lie at against-,the upper surface of the adjacent,

:edges of the4 sections I2, I3, It and` I5. The

sleeve 2| is then slippedover the reduced shank and a disc supporting member I is threadedly connected to the member 3, its lower end seating on the sleeve 2| which in turn forcibly holds the two assemblies 5 and 6 rmly in position. Another disc assembly and sealing assembly are then likewise positioned'on the shoulder ofthe member I, and a sleeve 22 is placed in position. If additional'disc and sealing assemblies are'desired, additional members Imay lbe connected together, and theassemblies positioned as above described. The upper end of the uppermost memberl is then threadedly connected to the pipe section Z3, the lower end of which holds the uppermost sleeve 22 in position.

As many of the pipe sections 23 as desired are then connected together, with the pipe section 24 at the upper end of the uppermost section 23, and the operating rod 26 is then connected to the upper end of the section 24. 4

Operation a The device is now placedin the well tubing and loweredL As it is lowered the-.ilappers Il, I8, I9 and 20, and the hinged sections I2, I3, I4

and I 5 are, free to pivot upward, which results in a reduction of. the overall diameter of all the a'ssemblies, thus permitting easy passage downward through the paraiiln coated tubing. In case paraiiln congests in the tubing below the scraper and enters the cage 1, the valve 9 is immediately forced to its seat and prevents the passage 4 from being obstructed by parain. After the device has been lowered a suiiicientdistance below the upper end of the parafllned section of the" tubing, its movement'is reversed. The hinged sections |2,- I3, I4 and I5, 'and the-sealing appers Il, I8, I9 and 2|). assume positions substantially at right angles to the wall of the tubing. the intermediate shoulders on the members A,I `and 3 limiting their pivotal movement downward. As the Vscraper is drawn upward a considerable quantity of paraflin accumulates above the uppermost disc and sealing assemblies and is drawn upward with the scraper. 'I'heball valve 9 remains open dur'- ing the upward travel ofthe scraper, and since the passages 4 and 2 intercommunicate, and also communicate with the bore of thepipe section 23 and with the bore of4 the upper pipe section 24, I'

no vacuum can possibly be created inthe tubing below the scraper, and thus there is no downward vacuum pull on the paraffin in the tubing above the scraper to cause the parailln to pass the disc assemblies. Any paraflin which does pass the above the next lower assembly and will act as a double seal against the further downward passage of paramn. This parailin in between the scrapsers will also aid considerably in guiding the entire device past the tubing joints which we have designated by the numeral 3|.

Should there be a column of Huid above the tool-in the well tubing such uid would be free to enter the ports 25 and pass downward through the device into the casing below it.

While we havev described and illustrated a speciflc embodiment of our invention we areaware that -numerous alterations may be made therein, and we do not wish to be limited except by the prior art and by the scope of the appended claims.

We claim:

1.- A device of the class described comprising a sectional elongated tube having a plurality of vertically spaced annular shoulders near its lower end, eachshonlder adapted to support a scraper assembly; a removable scraper assembly securely held on each of said shoulders, and comprising a scraper disc'assembly composed of a central hinge rin'g and four substantially quarter-l circular scraperblades hinged thereto, and adisc sealing assembly composed of a central hinge ring and iour appers hinged thereto, said ilappers adapted to seal the spaces between the edges of said scraper blades; and an upwardly closing normally open pressure closable valvecarried on the lower end of said elongated tube and adapted to prevent the passage of uid upward therethrough. v

2. A scraper assembly for a paramn scraper which includes a hollow central shank, said assembly comprising a scraper disc assembly including a central hinge ring adapted to be held in position by encircling the shank of the parailin scraper, and four, substantially quarter-circular scraper blades hinged to said ring; and v,also comprising a scraper disc sealing assembly which includes a central hinge ring likewise adapted to four appers hinged thereto, each flapper adapted to bridge and seal the space between two aduppermost disc assembly will, of course, be lodged .jacent scraper blades of said rst mentioned scraper disc assembly; and means for maintainlingtherelative radial positions of said vscraper -disc assembly and said scraper disc sealingv assembly. A y GLENN a. BUCKIEY. l WALTER A. MCGREW.

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