US2322419A - Paraffin scraping tool - Google Patents

Description

June 22, 1943. L. o. CRANFORD 2,322,419

PARAFFIN SCRAPING TOOL Filed Sept. 18, 1940 Enventor lb yaz L96 awn/fwd f Ui/g m, f wf (Ittqnieg Patented June 22, 1943 ATENT oer-ice Y Panama: sonarma 'roor.

Lloyd Lee Ottis Cranium-d, Baton Rouge, La. Application September 18, race, Serial No. 357,327

Claims.

The present invention relates to tools and more particularly to an oil well tool for scraping or removing paraflln or other accumulations from the casing or tubing thereof.

In'many oil wells paraflln or other accumulations collect on the inner walls of the well casing or tubing and seriously impairs and obstructs the free flow of oil therethrough.

It is an object of the present invention to provide a novel scraping tool for cleaning the walls of the well tubing in a rapid and eificient'manner.

A further object of the invention is to provide a device of this character which will easily cut through and remove heavily caked material encrusted on the walls of the well tubing.

Another object of the invention is the provision of a tool of this character which is ofv simple and inexpensive construction, eflicient and durable in use.

With the foregoing and other objects in view, the invention will be more fully described hereinafter, and will be more particularly pointed out in the claims appended hereto.

In the drawing wherein like symbols refer to like or corresponding parts through the several views.

Figure l is an elevation view of a well scraping tool embodying this invention.

Figure 2 is an enlarged transverse sectional view taken on line 2-2 of Figure 1.

Figure 3 is a similar view taken on line 3-3 of Figure 1, the parts shown in elevation.

Figure 4 is a similar sectional view taken on the line 5-4 of Figure 1.

Figure 5 is an enlarged cross-sectional view taken-along the line 55 of Figure l.- I

Referring more particularly to the drawing, the numeral lil designates an elongated body or rod which is tapered from its upper end to its lower or leading end, as illustrated in Figure 1. The upper end of the rod I0 is provided with a reduced and threaded extension Ii for removable connection to a suitable drill stem, anchor bar or other actuating member l2. A groove 53 is disposed in the upper end of the rod l0 below the coupling extension H to permit fishing of the tool from the well when necessary.

A series of four identical knives H are dis posed longitudinally of the rod It! at a point adjacent to but spaced from the lower or leading end of the rod. The knives M are equally spaced about the rod or shaft I0 in horizontal alignment and are semi-elliptical in shape, being set into longitudinal slots in the body of rod with their curvededges sharpened and extending outwardly from the surface of the rod. Screws i5 secure the knives H in the rod slots, as seen in Figures 1 and 4. v

A set of four scraping blades I6 are secured to the rod iii in horizontal positions, said blades being equally spaceda substantial distance apart. The upper blade I6 is spaced a substantial distance below the top of the rod in while the lower blade It is spaced a substantial distance above the group of knives It. A knife i1, identical with knives iii, lssecured .in a slot below each of the blades id in same manner as knives I4, but each knife ill is spaced about the circumference of the rod from the next adjacent knife H, as illustrated in Figure 1. As the rod i0 is tapered from the top to the bottom, the knives l'l pro- Sect radially beyond the knives below. Each knife ii is disposed in' longitudinal alignment with one of the knives l 4.

Each of the blades i6 is of arcuate shape, extending through an arc of about 240 and may be formed by bending a steel band to the requisite arcuate or circular form. A reinforcing bar in is welded or otherwise rigidly attached betweenthe open ends of the blade near the rear edges thereof. This bar I8 is bolted as at I9 Within a transverse slot in the surface of the rod ll, whereby the center of the bar is flush with the longitudinal surface of .the rod. Thus the bar it not only reinforces the blade I6 but also permits the blade to be spaced an equal distance at all points from the rod.

The blades is are beveled from the inside to the top and from the inside to the bottom to provide top and bottom sharpened cutting edges as illustrated in Figure 1.

This design and arrangement results in the paraflln being shaved from the walls of the tubing and as the same is shaved it passes readily behind the blades and is, of course caught in the stream of flowing oil and carried away.

The blades I6 are also spaced about the rod at points 90 apart and the center of each blade is disposed in vertical alignment with the knife ll immediately below it. The blade I6 at the upper end of rod I0 is radially wider than the next blade having the same radius as the bore of the well tube, and the blades are progressively smaller approaching the lower end of rod It.

In operation the rod 10 is lowered withinthe well casing and the knives ll will slice or cut into the paraffin or otheraccumulationcaked on the walls of the casing. The knives I! will enter the same cuts, slicing them deeper, while;

foreign matter or accumulation has been completely removed from the casing.

Whil the blades I6 will also shave or scrape the walls on the upward movement of the tool, the progressive cutting and scraping of the blades and knives is relied on to principally to'easily and effectively remove the caked material from the casing walls. Without this progressive action of cutting and scraping deeper and deeper as the tool progresses in its downward stroke, the caked material which collects on the walls of the casing ofiers too great of a resistance to be removed effectively by ordinary scraping methods.

Although the knives and blades illustrated are in groups of four spaced 90 apart, they may be obviously of any desired number, preferably equally spaced about the circumference of the rod [0.

An important feature of this invention is the action of longitudinally slicing or cutting the caked material before each successive scraper blade is brought into play, and the progressive deepening of the slicing and scraping action.

It is obvious that various changes and modifications may be made in the details of construction and design of the above specifically described embodiment of this invention without departing frim the spirit thereof, such changes and modifications being restricted only by the scope of the following claims:'

' What is claimed is:

1. In a well scraper, an elongated body member, a series of slicing knives with longitudinally arranged cutting edges secured on said body member adjacent the leading end thereof, said knives extending radially from the body member in longitudinally spaced staggered relation about its circumference, and a series of transverse scraping blades secured to the body member above th slicing knives, said scraping blades and slicing knives being spaced apart longitudinally of the body member in alternate arrangement thereon, said scraper blades being disposed in staggered overlapping relation to one another and having arcuate scraping edges, each scraping blade of the series extending radially beyond the scraping blades disposed between it'and the leading end of the body member.

2. In a well scraper, an elongated body member, a series of slicing knives with longitudinally arranged cutting edges secured on said body -member adjacent the leading end thereof, said knives extending radially from the body mem- 'ber inlongitudinally spaced staggered relation about its circumfernece, and a series of transverse scraping blades secured to the body member above the slicing knives, said scraping blades and slicing knives being spaced apart longitudinally of the body member in alternate arrangement thereon, said scraping blades being disposed in staggered relation and having arcuate scraping edges, each scraping blade of the series extending radially beyond the scraping blades disposed between it and the leading end of the body member, and a knife with a longitudinally disposed radially extending slicing blade arranged in spaced relation ahead of each scraping blade and in alignment with the central portion of said blade.

3. In a well scraper, an elongated body member, a series of slicing knives with longitudinally arranged cutting edges secured on said body member adjacent the leading end thereof, said knives extending radially from the body member in longitudinally spaced staggered relation about its circumference, and a series of transverse scraping blades secured to the body member above the slicing knives, said scraping blades and slicing knives being spaced'apart longitudinally of the body member in alternate arrangement thereon, said scraper blades being disposed in staggred relation and having arcuate scraping edges, each scraping blade of the series extending radially beyond the scraping blades disposed between it and the leading end of the body member, and a knife with a longitudinally disposed, radially extending slicing blade arranged in spaced relation ahead of each scraping blade and in alignment with the central portion of said blade, each of said last named slcing knives being disposed in longitudinal alignment with one of the slicing knives at the leading end of the body member and extending radially therebeyond.

4. In a well scraper, a body member, a series of arcuate scraping elements carried by the body l member, said scraping elements extending aircumferentially-about a body member and being spaced apart longitudinally of the body member and disposed in staggered relation circumferentially of the body member, each of the scraping elements ofthe series projecting radially outwardly beyond the scraping elements between it and the leading end of the body member, and

- a series of circumferentially staggered longitudinally spaced slicing knives secured to said body member, each knife in the series being disposed below and in longitudinal alignment with one of the staggered scraping element and adapted to slice the material on the well casing ahead of the scraping elements.

5. In a well scraper, an elongated body member, a series of longitudinally spaced arcuate transverse scraper. blades secured to the body member in circumferentially staggered relation around the member and adapted to scrape material from the walls of a well casing and a slicing knife disposed longitudinally on said body mem-

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