US3044552A

US3044552A - Paraffin scraper

Info

Publication number: US3044552A
Application number: US835976A
Authority: US
Inventors: Marshall L Claiborne
Original assignee: Individual
Current assignee: Individual
Priority date: 1959-08-25
Filing date: 1959-08-25
Publication date: 1962-07-17
Anticipated expiration: 1979-07-17

Description

July 17, 1962 M. L. CLAIBORNE PARAFFIN SCRAPER Filed Aug. 25, 1959 RSI-IALL L. CLAlBORNE INVENTOR.

- 3,044,552 PARAFFIN SCRAPER Marshall L. Claiborne, 206i W. Alto, Hobbs, N.V Mex. Filed Aug. 25, 1959, Ser. No. 835576 3 Claims. (Cl. 16d-170) This invention pertains to oil Wells and more particularly to a device for scraping para'in from the inside or" the production tube of a free owing oil well.

This device is particularly designed and adapted to be used upon oil wells which have sufficient pressure to cause the oil to flow freely through a tube to the surface of the ground. A common problem with such type oil wells is the collection and accumuiation of paraffin on the inside of the tubing.

This tool operates on the principle that the liow of the well may be stopped by closing a valve at the top of the well. Therefore any object in the Ytube which is heavier than the liquid in the tube will fall. On the other hand, if the valve at the top of the well is open, any object in the well will be carried upward with the iow of oil in the well.

An object of this invention -is to provide such a free fall device which will effectively scrape the paratiin from the inside of the tube.

Another object is to provide such a tool which has little or no dificulty in freely falling when there is no ow of oil in the well yet which has good scraping action on both the downward and upward trip.

A further object of this invention is to provide a tool which is easy to catch and hold within the lubricator -at the upper portion of the tube.

Still further objects are to achieve the above with a device that is sturdy, compact, durable, simple, and reliable, yet inexpensive and easy to manufacture.

The specific nature of the invention as Well as other objects, uses, and advantages thereof will clearly appear from the following description and from the accompanying drawing, in which:

FIG. 1 is an elevational view of said tool in the tube.

FIG. 2 is a partial longitudinal section of the joint between the upper and lower section of the tool.

FIG. 3 `is a partial longitudinal section of the joint between the lower section of the tool and the stop member.

As may be seen in the accompanying drawing, the tool is basically divided in two sections. As this general type of tool is well known, the lubricator and the catch in the bottom have not been shown.

The upper section of the tool is basically a cylindr-ical body or member 12 which is closed at the top end. The top end is closed by shaft 14 for the easy engagement of fishing tools, generally called a fishing neck.

Around the exterior of the body 12 are two helical vanes 16. These vanes are welded or otherwise iirmly secured to the body. The outside diameter of the tool with the vanes is only slightly smaller than the inside diameter of the tube within which the tool works.

Likewise lower section 18 has body 20 which is of cylindrical form. The body has two vanes 22 helically around it. As may be seen, both the bodies of the upper and lower section are made of tubular material. The top of the lower section body 20 has a plug 24. The outside diameter of the plug is the same as the inside diameter of the body so thereds a snug iit. Holes may be bored in the side of the body 20 so that the plugis welded in place through the holes to the body 20. Pintle 26 rises coaxially with the tubular body 20. It is an integral part of the plug 24. The pintle extends through hole 23 of Washer 30 which is 4at-tached to the lower end of the tubular upper body 12. Holes may be bored through the upper body 12 to weld the washer 30 in place. As may be seen, the washer has a substantial 3,4%,552 Patented July l?, 1962 thickness. The hole 28 is larger than the outside diameter of the pintle 26. Therefore there is a certain amount of play or possibility of vibration between the upper body and the lower body. A protuberance or stop or nut 32 is screwed onto threads at the top of the pintle and welded into place at the top of the pintle which is above the washer. As stated before, the whole connection is sornewhat rough and permitting and encouraging Vibration for reason which will be explained later.

Stop 34 is below vthe bottom section. The outside diameter of the stop is larger than the outside diameter of the tubular body 20 which is of the same diameter as the tubular body 12. However the diameter of the stop is less than the outside diameter of the entire tool including vanes. Likewise extending vertically upward from the stop and coaxial with the tubular members s pintle 36 which extends through washer 38 which is attached to the lower body in the same manner as Washer 3G is attached to the upper body. Likewise a nut or not to hang easily because each of the sections will tend to spiral as it goes down. 'If the tool hits some obstruction in the tube, the parts will spiral around as they go down. However, because the swivel between the lower member and the upper member is not machined to perfection, there will be a certain amount of friction and vibration. This prevents perfect spiraling and `accomplishes a great deal of paraffin removal. If only a single member is used which has a spiral in only one direction, it will tend to make a helical track down the inside of the tube and following this same track on repeated trips. If right and left handed veins are used on a single member with no possible rotation between the two sections, there is no spiraling at all when the tool is traveling and more likely the tool will become stuck on paraiiin deposits as it falls.

I have found it desirable to add a stop on the bottom which is mounted for rotation. When the tool'strikes the catch which is mounted in the tube at the lower extreme of the tools travel, there is no excessive rotation against the catch. Likewise when the tool is blown upward and the tool is caught in the lubricator at the top of the tube, the stop can rest without having a friction drag on the catch even if 4the bottom section is still rotating due to the passage of uid by it.

Specifically I have found that following dimensions give good resultsfor a tool adapted to work within a 2 inch LD. tube. The bodies 12 and 20 are made from 1/2 inch steel pipe (.840 inch O.D.) each about 81/2 inches long. The

vanes

16 and 22 each make one complete revolution around the body and are constructed from 12 guage steel welded to the body. The entire tool is 20 inches long and weighs three pounds. The diameter of across the vanes is 1% inches and the diameter of the stop is 15/8 inches.

tI-t will be apparent that the embodiment shown is only exemplary and that various modifications can be made in construction, materials, and arrangements within the scope of the invention as defined in the appended claims.

and the vanes on the bottom portion rotating in a second direction, a pintle attached to one of said portions, a washer attached to the other of said portions, said pintle extending through said washer and having a stop at the l end ofthe pintle which is beyond said washer, so that the two membersv are connected together for relative rotation but with only slight axial movement. A

2. The invention as dened in claim'l with the addition of a disc shaped stop upon the bottom of the bottom portion co-axial therewith, said stop being of lesser diameter than the outside diameter of said vanes but of greater diameter than the diameter of the portion to which the varies are attached, said stop having a pintle extending upward from the top thereof, said bottom portion having a washer in its bottom, said stop pntle extending through said bottom washer, a protuberance upon the top of the pintle Which is above the Washer, thus mounting the stop for relative rotation to the bottom portion but little axial movement relative to the bottom portion. Y Y

3. A paralin scraper for oil Wells comprising: an upper cylindrical member with helical vanes on the exterior thereof, said helical vanes rotated around the outside of the member in a first direction; a lower second cylinfdrical member with helicalvanes on the outside thereof, the vanes of the second member rotated around the outside of the second member in a second direction; said cylindrical members being arranged coaxially vertically within a tubular member of said oil Well, means connecting said `first and second members for Vfree rotation in all positions relative to each other, but for only slight axial movement with respect to each other; anda stop on the bottom oi the lower of the two members, said stop having a smooth exterior surface, and said stop being mounted for free rotation relative to the lower of the two members.

References Cited in the tile of this patent UNITED STATES PATENTS 1,372,904 Regenier Mar. 29', 1921 1,810,260 Swinford f I une 16, 1931 r2,201,680 Haynes May 21, 1940 2,326,528 Festervan et al. Aug. 10,. 1943 2,636,565 Williams Apr.l28, 1953 2,679,905 Mangum et al. June 1, 1954